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HomeMy WebLinkAbout2023-01-17 PC Regular Meeting Agenda Packet City of Palm Desert Page 1 PLANNING COMMISSION CITY OF PALM DESERT, CALIFORNIA AGENDA (HYBRID MEETING) City Hall – Council Chamber 73510 Fred Waring Drive Palm Desert, CA 92260 Pursuant to Assembly Bill 361, this meeting may be conducted by teleconference. • To participate via Zoom, use the following link: https://palmdesert.zoom.us/j/84739707419. • To participate via phone: Dial (213) 338-8477 or (602) 753-0140, enter the Zoom Webinar ID: 847 3970 7419 followed by #. Indicate that you are a participant by pressing # to continue. During the meeting, press *9 to add yourself to the queue and wait for the Recording Secretary to announce your name/phone number. Press *6 to unmute your line and limit your comments to three minutes. • Written public comment may also be submitted to planning@cityofpalmdesert.org. Emails received by 3:00 p.m. prior to the meeting will be distributed to the Commission. Any correspondence received during or after the meeting will be distributed to the Commission as soon as practicable and retained for the official record. Emails will not be read aloud except as an ADA accommodation. 1. CALL TO ORDER 2. ROLL CALL 3. PLEDGE OF ALLEGIANCE 4. NON-AGENDA PUBLIC COMMENT: This time has been set aside for the public to address the Planning Commission on issues that are not on the agenda for up to three minutes. Because the Brown Act does not allow the Commission to act on items not listed on the agenda, members may briefly respond or refer the matter to staff for a report and recommendation at a future meeting. 5. CONSENT CALENDAR: All matters listed on the Consent Calendar are considered routine and may be approved by one motion. The public may comment on any items on the Consent Agenda within the three-minute time limit. Individual items may be removed by Commissioners for a separate discussion. Tuesday January 17, 2023 6:00 p.m. Regular Meeting Planning Commission Agenda January 17, 2023 City of Palm Desert Page 2 A. APPROVAL OF MINUTES RECOMMENDATION: Approve the Planning Commission Regular Meeting minutes of December 6, 2022. CONSENT ITEMS HELD OVER: Items removed from the Consent Calendar for separate discussion are considered at this time. 6. ACTION CALENDAR None 7. PUBLIC HEARINGS: Anyone who challenges any hearing matter in court may be limited to raising only those issues he or she raised at the public hearing described herein, or in written correspondence delivered to the Planning Commission at, or prior to, the public hearing. Remarks shall be limited to a maximum of three minutes unless the Planning Commission authorizes additional time. A. CONSIDERATION TO ADOPT A NOTICE OF EXEMPTION PURSUANT TO THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA); AND APPROVE AN AMENDMENT TO A PRECISE PLAN AND CONDITIONAL USE PERMIT TO EXPAND AN EXISTING CARMAX AUTO SALES FACILITY BY CONSTRUCTING A BUILDING ADDITION TO AN EXISTING SALES BUILDING, A NEW PRIVATE CARWASH TUNNEL, EXPANSION OF AN EXISTING CUSTOMER PARKING LOT, AND CONSTRUCTION OF A NEW SALES STAGING AREA AT 73450 DINAH SHORE DRIVE (APN 694-060-034 AND -036) RECOMMENDATION: Waive further reading and adopt Planning Commission Resolution No. 2827 to: 1. Adopt a Notice of Exemption for a Class 32 Categorical Exemption in accordance with CEQA. 2. Approve Precise Plan/Conditional Use Permit 17-059 Amendment No. 1 and Environmental Assessment 22-0007 to expand an existing CarMax Auto Superstore located at 73450 Dinah Shore Drive. 8. INFORMATIONAL REPORTS & COMMENTS A. SUMMARY OF CITY COUNCIL ACTIONS B. COMMITTEE MEETING UPDATES 1. Cultural Arts Committee 2. Parks and Recreation Commission C. PLANNING COMMISSIONERS D. CITY STAFF E. ATTENDANCE REPORT Planning Commission Agenda January 17, 2023 City of Palm Desert Page 3 9. ADJOURNMENT: The next Regular Meeting will be held on February 7, 2023, at 6:00 p.m. AFFIDAVIT OF POSTING I hereby certify under penalty of perjury under the laws of the State of California that the foregoing agenda for the Planning Commission was posted on the City Hall bulletin board and City website not less than 72 hours prior to the meeting. Monica O’Reilly Recording Secretary PUBLIC NOTICES Agenda Related Materials: Pursuant to Government Code §54957.5(b)(2) the designated office for inspection of records in connection with this meeting is the Development Services Department, City Hall, 73-510 Fred Waring Drive, Palm Desert. Staff reports for all agenda items and documents provided to a majority of the legislative bodies are available for public inspection at City Hall and on the City’s website at www.cityofpalmdesert.org. Americans with Disabilities Act: It is the intention of the City of Palm Desert to comply with the Americans with Disabilities Act (ADA) in all respects. If, as an attendee or a participant at this meeting, or in meetings on a regular basis, you will need special assistance beyond what is normally provided, the city will attempt to accommodate you in every reasonable manner. Please contact the Office of the City Clerk, (760) 346-0611, at least 48 hours prior to the meeting to inform us of your needs and to determine if accommodation is feasible. City of Palm Desert Page 1 PLANNING COMMISSION CITY OF PALM DESERT, CALIFORNIA MINUTES Pursuant to Assembly Bill 361, this meeting was conducted by teleconference, and there was in-person public access to the meeting location. 1. CALL TO ORDER A Regular Meeting of the Planning Commission was called to order by Chair DeLuna on Tuesday, December 6, 2022, at 6:00 p.m. 2. ROLL CALL Present: Commissioners John Greenwood, Ron Gregory, Vice-Chair Joseph Pradetto, and Chair Nancy DeLuna. Commissioner Lindsay Holt arrived at 6:01 p.m. Absent: None. Staff Present: Robert Hargreaves, City Attorney, Richard D. Cannone, AICP, Director of Development Services; Rosie Lua, Deputy Director of Development Services; Nick Melloni, Senior Planner; and Monica O’Reilly, Executive Administrative Assistant. 3. PLEDGE OF ALLEGIANCE Chair DeLuna led the Pledge of Allegiance. 4. NON-AGENDA PUBLIC COMMENT: None. 5. CONSENT CALENDAR: The staff report(s) and Zoom video of the meeting are available on the City’s website. Click on the following link to access: www.cityofpalmdesert.org/our- city/committees-and-commissions/commission-information. Tuesday, December 6, 2022 6:00 p.m. Regular Meeting Planning Commission Minutes December 6, 2022 City of Palm Desert Page 2 ALL ACTIONS ARE DRAFT, PENDING APPROVAL OF THE MINUTES A. APPROVAL OF MINUTES RECOMMENDATION: Approve the Minutes of November 15, 2022. MOTION BY VICE-CHAIR PRADETTO, SECOND BY COMMISSIONER GREENWOOD, CARRIED 5-0, to approve the Planning Commission Regular Meeting minutes of November 15, 2022. CONSENT ITEMS HELD OVER: None. 6. ACTION CALENDAR None. 7. PUBLIC HEARINGS A. CONSIDERATION TO ADOPT A NOTICE OF EXEMPTION PURSUANT TO THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA); AND APPROVAL OF A PRECISE PLAN TO DEVELOP AN APPROXIMATELY 52,528-SQUARE-FOOT SELF- STORAGE FACILITY ON A 1.87-ACRE SITE LOCATED AT THE NORTHWEST CORNER OF DINAH SHORE DRIVE AND DICK KELLY DRIVE (APNs 694-240-009, 010, AND 021) Senior Planner Melloni presented the staff report and responded to Commissioner inquiries. Chair DeLuna opened the Public Hearing. Mr. Jim Fitzpatrick, the applicant, thanked City staff and stated they accept all the Conditions of Approvals as presented. He and his team were available to answer any questions. Mr. Josef Jonathan, a Palm Desert resident and business owner, voiced support for the project. There being no one desiring to speak, the Public Hearing was closed. MOTION BY VICE-CHAIR PRADETTO, SECOND BY COMMISSIONER HOLT, CARRIED 5-0, approving Planning Commission Resolution No. 2825 to: 1. Adopt a Notice of Exemption for a Class 32 Categorical Exemption in accordance with CEQA. 2. Approve Precise Plan (PP)/Environmental Assessment (EA) 22-0005 for the development of a 52,528-square-foot self-storage facility, including on-site and off-site improvements on a 1.87-acre site located at the northwest corner of Dinah Shore Drive and Dick Kelly Drive. Planning Commission Minutes December 6, 2022 City of Palm Desert Page 3 ALL ACTIONS ARE DRAFT, PENDING APPROVAL OF THE MINUTES B. CONSIDERATION TO ADOPT A MITIGATED NEGATIVE DECLARATION PURSUANT TO CEQA; AND APPROVE A PRECISE PLAN AND CONDITIONAL USE PERMIT TO CONSTRUCT A 394-UNIT MULTIFAMILY APARTMENT COMMUNITY CONSISTING OF 13 THREE-STORY (3) BUILDINGS, ONE (1) TWO-STORY FITNESS CENTER, ONE (1) SINGLE-STORY CLUBHOUSE, TWO (2) POOL AREAS, AND PRIVATE OUTDOOR RECREATION AREAS ON AN 18.31-ACRE SITE LOCATED AT THE SOUTHWEST CORNER OF FRANK SINATRA DRIVE AND PORTOLA AVENUE (APNs 620-400-030 AND 620-400-031) Commissioner Gregory announced he had a conflict of interest due to his employer and recused himself. He left the meeting at 6:21 p.m. Senior Planner Melloni narrated a PowerPoint presentation and responded to Commission inquiries. Deputy Director of Development Services Lua mentioned comments from the public were attached to the staff report. Staff emailed comments to the Commission received after the agenda was posted and kept for the record. Ms. Lua addressed an inquiry regarding Regional Housing Needs Allocation (RHNA). Chair DeLuna opened the Public Hearing. Mr. Cody Dietrich, the applicant, introduced his team and presented a PowerPoint presentation about the project. Ms. Christine Pecard, the project architect, continued with the presentation, focusing on the project’s architecture. The applicant and City staff responded to Commission inquiries. Mr. Mark Shabashov, a Palm Desert resident, voiced his opposition to the project. Mr. Don Mess, a Palm Desert resident, voiced his opposition to the project. Ms. Kathleen Kendrick, a Palm Desert resident, voiced her opposition to the project and asked why the comments and questions period was short. Ms. Cam Cameron, a Palm Desert resident, voiced her opposition to the project. Mr. Al Stanger, a Palm Desert resident, voiced his concern with zoning in the area that would allow high-density development and asked when the City changed the zoning. Mr. Dave Sams, a Palm Desert resident, voiced his opposition to the project. Ms. Edith Taylor, a Palm Desert resident, voiced her opposition to the project. Mr. Jeff Cameron, a Palm Desert resident, voiced his opposition to the project. Mr. Jeremy Cowley, a Palm Desert resident, voiced his opposition to the project. Planning Commission Minutes December 6, 2022 City of Palm Desert Page 4 ALL ACTIONS ARE DRAFT, PENDING APPROVAL OF THE MINUTES Ms. Pamela Hoekstra, a Palm Desert resident, voiced her opposition to the project. There being no others desiring to speak, the Public Hearing was closed. Deputy Director Lua interjected and asked Chair DeLuna to reopen the Public Hearing to allow City staff and the applicant to respond to questions. Chair DeLuna reopened the Public Hearing. Senior Planner Melloni responded to concerns/questions made by the public. Mr. Dietrich also responded to concerns/questions. City Attorney Hargreaves briefed the Planning Commission on the Housing Accountability Act (HAA) and responded to questions. At this point, there was discussion regarding land use and density, with staff responding to additional questions. The applicant responded to questions from the Commission. There being no others desiring to speak, the Public Hearing was closed. After comments made by Commissioner Pradetto, he moved for approval. Commissioner Holt interjected, stating that she would want to incorporate a Condition of Approval. Commissioner Pradetto withdrew his motion. Commissioner Greenwood added that he would also want to add a Condition of Approval to the landscape plans. City staff proposed wording for the Condition of Approvals, noting that the Planning Commission could revise it. Chair DeLuna reopened the Public Hearing. The applicant accepted the proposed additional Condition of Approvals and responded to questions about building color changes. There being no other comments, the Public Hearing was closed. Following Commissioner comments, MOTION BY COMMISSIONER GREENWOOD, SECOND BY VICE-CHAIR PRADETTO, CARRIED 4-0 (GREGORY RECUSE), approving Planning Commission Resolution No. 2826 to: 1. Adopting a Mitigated Negative Declaration and Mitigation Monitoring Reporting Program for the project pursuant to CEQA. 2. Approving PP/Conditional Use Permit (CUP)/EA 22-0006 for the development of a Planning Commission Minutes December 6, 2022 City of Palm Desert Page 5 ALL ACTIONS ARE DRAFT, PENDING APPROVAL OF THE MINUTES 394-unit multifamily apartment development at the southwest corner of Frank Sinatra Drive and Portola Avenue. 3. The applicant shall install additional landscaping for screening purposes along Frank Sinatra Drive, west of Portola Avenue, and east of Shepherd Lane; and the landscape plans shall be reviewed and approved by City staff and shall be installed prior to the Certificate of Occupancy of the first building. 4. Prior to the building permit issuance, the Applicant shall submit an alternative exterior color scheme for Building No. 2, as shown on the CUP Site Plan dated October 3, 2022, for review and approval by the Director of Development Services. 8. INFORMATIONAL REPORTS & COMMENTS A. SUMMARY OF CITY COUNCIL ACTIONS None. B. COMMITTEE MEETING UPDATES 1. Cultural Arts Committee None. 2. Parks and Recreation Commission Senior Planner Melloni stated that there were no reportable actions, and City staff provided updates on existing parks. C. PLANNING COMMISSIONERS None. D. CITY STAFF Deputy Director Lua mentioned that there are no agenda items for the Planning Commission meeting of December 20. E. ATTENDANCE REPORT The attendance report was provided with the agenda materials. The Commission took no action on this matter. 9. ADJOURNMENT The Planning Commission adjourned the meeting at 8:33 p.m. Respectfully submitted, Monica O’Reilly, Executive Administrative Assistant Planning Commission Minutes December 6, 2022 City of Palm Desert Page 6 ALL ACTIONS ARE DRAFT, PENDING APPROVAL OF THE MINUTES Recording Secretary ATTEST: Richard D. Cannone, AICP, Director of Development Services Secretary APPROVED BY THE PLANNING COMMISSION: XX/XX/XXXX Page 1 of 12 CITY OF PALM DESERT STAFF REPORT MEETING DATE: January 17, 2023 PREPARED BY: Nick Melloni, Senior Planner REQUEST: CONSIDERATION TO ADOPT A NOTICE OF EXEMPTION PURSUANT TO THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA); AND APPROVE AN AMENDMENT TO A PRECISE PLAN AND CONDITIONAL USE PERMIT TO EXPAND AN EXISTING CARMAX AUTO SALES FACILITY BY CONSTRUCTING A BUILDING ADDITION TO AN EXISTING SALES BUILDING, NEW PRIVATE CARWASH TUNNEL, EXPANSION OF AN EXISTING CUSTOMER PARKING LOT, AND CONSTRUCTION OF A NEW SALES STAGING AREA AT 73450 DINAH SHORE DRIVE (APN 694- 060-034 AND -036) RECOMMENDATION: Waive further reading and adopt Planning Commission Resolution No. 2827 to: 1. Conduct a public hearing and receive public testimony. 2. Adopt a Notice of Exemption for a Class 32 Categorical Exemption in accordance with CEQA. 3. Approve Precise Plan/Conditional Use Permit 17-059 Amendment No. 1 and Environmental Assessment 22-0007 to expand an existing CarMax Auto Superstore located at 73450 Dinah Shore Drive. ARCHITECTURAL REVIEW COMMISSION RECOMMENDATION (ARC): The project appeared before the ARC for the design review of architecture and landscape on November 22, 2022, and December 13, 2022. On November 22, 2022, the project was presented to the ARC for design review consideration. After discussion of the plans, Chair Vuksic, seconded by Commissioner McAuliffe motioned to continue the case in a 6-0 vote subject to the following comments: 1. The applicant shall construct the wall enclosing the vehicle staging area with a tan split-face block and pilasters facing Dinah Shore Drive, and the northern property line spaced no greater than 30 feet apart. 2. All roof drainage on the proposed additions shall utilize internal roof drains. 3. Parapet ends on new tower elements shall return 12 feet onto the existing roof. 4. Windows of the new addition should be recessed to match the existing south façade. 5. Header detail on the new tower element should be recessed a minimum of eight inches (8”). City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 2 of 12 6. East end of the new building addition and existing building should be revisited for more dimension and forms. 7. Revisit the steel canopy design to look more integral to the existing architecture. On December 13, 2022, the ARC reviewed the redesigned plans and determined that the revisions incorporated into the plan design adequately addressed their initial comments. Commissioner McAuliffe, seconded by Commissioner Colvard motioned to approve the design review subject to the following conditions of approval: 1. The applicant shall construct the wall enclosing the vehicle staging area with a tan split-face block and pilasters facing Dinah Shore Drive, and the northern property line spaced no greater than 30 feet apart. 2. All roof drainage on the proposed additions shall utilize internal roof drains except on the north elevations of the main sales and service building. 3. The areas indicated by dark earth tone stucco located on the tower elements of the south and east elevations of the sales addition shall be recessed a minimum of eight inches (8”) from the fascia of the tower element. Final construction drawings shall provide sufficient details for this change. The ARC conditions of approval of December 13, 2022, have not been incorporated into the plan set presented to the Planning Commission. The Planning Commission Resolution will include the aforementioned conditions of approval. EXECUTIVE SUMMARY: The project applicant, Michael Baker International on behalf of CarMax Auto Superstore, has requested approval of an amendment to an existing Precise Plan (PP) and Conditional Use Permit (CUP), PP/CUP 17-059, and an Environmental Assessment (EA) 22-0007 to expand an existing CarMax facility located at 73450 Dinah Shore Drive. The expansion will include a 2.17-acre portion of the project site consisting of the following modifications: A. A 2,351-square-foot sales office expansion to an existing 6,841-square-foot sales/auto service building. B. A new 923-square-foot private carwash building for service of onsite vehicles. C. A new 560-square-foot shade canopy addition. D. Expansion to the existing parking lot, adding 55 new on-site parking spaces for customers and employees. This expansion will require the removal of 14 existing spaces resulting in a net increase of 40 spaces to the site for a total of 100 parking spaces. E. Construction of a new 176-space sales staging area on a 1.9-acre vacant parcel located west of CarMax will be enclosed by a six-foot-high (6’) block wall and feature new parking lot lighting. F. On-site landscaping. On August 1, 2017, the Palm Desert Planning Commission adopted Resolution No. 2703 approving PP/CUP 17-059 to construct a 6,840-square-foot auto sales and service building, 64 employee parking spaces, and 178 sales lot parking spaces on a 4.23-acre site located at 73500 Dinah Shore Drive. Construction of the site was completed in 2019, and the site has remained in continuous operation. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 3 of 12 The project has been reviewed for full conformance with the applicable requirements of the Palm Desert Zoning Ordinance and is consistent with the Palm Desert General Plan. BACKGROUND/ANALYSIS: a) Property Description: The project site is comprised of two contiguous parcels totaling 6.13 acres on the north side of Dinah Shore Drive at 73450 (Parcel “A” – APN 694-060-036) and (Parcel “B” – APN 694-060-034) Dinah Shore Drive at the intersection of Gateway Drive. Parcel A is a 4.23-acre site that is developed with the existing CarMax auto sales development, including a sales building, auto service building, vehicle staging area, and customer parking lot. Parcel B is a vacant 1.9-acre site, which has been rough graded adjoining the existing CarMax development. The project site is surrounded by existing light industrial and commercial development to the west, south, and east and by the City limits to the north. The frontage of the site has been improved with a full-width roadway, curb, gutter, and sidewalk. There are two access points available to the site. The primary entry is at the signalized intersection of Dinah Shore Drive and Gateway Drive. A secondary exit is located at the eastern edge of the site, which is used for emergency and employee access only and is shared with the neighboring warehouse store. The project is within the boundaries of Assessment District 2004-02, which provides stormwater drainage infrastructure for the project. The northern edge of the site is developed with a concrete-lined drainage channel, which conveys a portion of the site’s stormwater overflows flow to the retention basin at the northwest corner of Dinah Shore Drive at Portola Avenue. A 20-foot storm drain, and sewage easement bifurcates the site near the primary entrance. b) Current Zoning & General Plan Land Use Designation: Figure 1 – Adjacent Land Use and Designations Existing Uses General Plan Zoning Project Site CarMax/Vacant Employment Service Industrial (SI) North Drainage Area/City Limit Employment/County Zoning SI/County Zoning South Light-Industrial Development Employment SI East Light-Industrial Employment SI West Monterey Crossings Commercial Center Regional Retail Regional Planned Commercial/Monterey Crossings Specific Plan Project Description: The project amendment includes three (3) entitlements, consisting of the following: 1. Precise Plan (PP) 17-059 Amendment No. 1: To allow the development of the building addition, expanded parking, landscaping, lighting, and related improvements. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 4 of 12 2. Conditional Use Permit (CUP) 17-059 Amendment No. 1: To allow the development of an auto sales facility as required by the Palm Desert Zoning Ordinance for the Service Industrial (SI) zoning district. 3. Environmental Assessment (EA) 22-0007: CEQA Review for a Class 32 Categorical Exemption (Infill Project). In addition to the proposed project amendment, an application has been submitted for a Parcel Map Waiver (PMW22-0008) to merge a 4.23-acre parcel and 1.9-acre parcel into a single 6.23-acre parcel to include the entire project site. a) Operations: The expansion will add a new sales staging area as an overflow lot where vehicles will be staged and stored for processing and service by CarMax. Presently, there is an existing staging area located behind (north) the existing CarMax auto sales and service building for the same purpose. This staging area will be non-striped as CarMax employees will park vehicles parallel within the space to manage storage. Existing uses at the site will largely remain the same. Truck deliveries of vehicles are anticipated to occur at a volume of approximately 20-25 delivery trucks per week. The facility currently employs 54 total sales associates, with approximately 41 employees on-site at any time. The proposed expansions will increase the total number of employees to 65. Hours of Operation will continue as follows: Showroom: Monday–Friday 10:00 a.m. to 9:00 p.m., Saturday 9:00 a.m. to 9:00 p.m., and Sunday 12:00 p.m. to 7:00 p.m. Service: Monday-Friday 7:30 a.m. to 6:00 p.m. b) Site Plan: The expansion will add 55 new public parking spaces and an enclosed 176-space sales staging area to the western portion of the site. The public parking area will be striped and landscaped in accordance with City requirements for parking lot design (Palm Desert Municipal Code (PDMC) Sections 25.46 and 25.52.050). The western portion of the site (staging expansion area) is an overflow lot where vehicles will be staged and stored for processing and service by CarMax. This lot will not be striped or landscaped as it will be used exclusively for CarMax business operations and will be non-accessible to the public. Vehicles within the space will be parked in tandem for storage by CarMax staff. This operation is consistent with the existing vehicle staging area located on the CarMax site to the north of the main sales building. The sales/staging lot will be screened by a continuous six-foot-high (6’) masonry split-face block wall with a two-inch (2”) cap and landscape area along the perimeter of the lot. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 5 of 12 In addition to the expanded parking areas, the project will make additions to the existing facility by adding a carwash tunnel within the existing sales staging area, a sales area expansion to the main building, and the addition of a free-standing canopy. Figure 2 – Project Site Plan c) Access and Circulation: Access to the site is provided at the signalized intersection of Dinah Shore Drive and Gateway Drive. The project will not add new vehicle access drives onto Dinah Shore Drive. There is an existing public sidewalk developed along the entirety of the project frontage. Internal access and circulation will be maintained for the additions to the public parking lot. The vehicle sales staging area will be separated from the public parking areas by an electric vehicle gate. d) Architecture: The project will add a 2,351-square-foot building addition to the primary building, which will contain an expanded sales area and employee breakroom area. The architecture of this addition is contemporary and will match the existing finishes and architectural forms used on the primary building. The materials include stucco, finished in earth-tone colors, split-face concrete masonry unit (CMU) block, metal shade awnings, and pre-finished coping. The height of this addition will match the existing service building at a height of 18 feet, eight inches (8”), and a tower element at 21 feet, eight inches (8”). The proposed 935-square-foot carwash tunnel will be located within the existing vehicle sales staging area at the north edge of the site. The tunnel will feature tan-colored stucco and tan split-face CMU block to match the primary building materials. The structure will have a flat roof with a maximum height of 17 feet, four inches (4”). City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 6 of 12 The proposed 560-square-foot shade canopy will be placed on the western building elevation, adjacent to an existing port cochere at the service entrance. This structure will be designed to match the existing canopy and is designed with matching roof height and exterior materials. The roof of the sales additions to the primary building will be flat with a continuous two-foot (2’), eight-inch (8”) parapet. No rooftop equipment is proposed on the addition area. New rooftop equipment for the sales addition will be placed on the existing sales building and will be screened by an existing five-foot-tall (5’) parapet. Figure 3 – Project Architecture e) Exterior Lighting: The project will add 20 new exterior light fixtures consisting of 16 light poles and four (4) exterior wall packs. Two (2) existing light poles located at the northern edge of the customer lot will be relocated. The light poles will have a total height of 26’-0” above grade and are located within the customer parking lot and perimeter of the sales lot/staging area. The average foot- candle rating within the sales lot/staging area will be 3.75. The wall pack lights are placed on the new carwash building. All new exterior light fixtures will be designed with light emitting diodes, which are directed downward, full cut-off with additional shielding to restrict glare at property lines to meet requirements of the Outdoor Lighting Ordinance (PDMC Chapter 24.16). The design of these fixtures will match the existing lighting at City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 7 of 12 the site. The system will be controlled by an automated Energy Management System, and all fixtures will be dimmed after operational hours (9:00 p.m. Monday-Saturday, and 7:00 p.m. on Sunday). f) Landscaping: The project will propose additional landscape plantings with the proposed expansions. This landscaping is primarily located along the perimeter of the sales lot area and throughout the expanded customer sales lot. Landscaping will not be located within the sales lot due to potential impacts on operational requirements. The landscape for the site consists of a mix of desert- appropriate live plantings, which include: Trees • Golden Wreathwattle (Acacia Saligna), Blue Palo Verde (Parkinsonia Floridia), Honey Mesquite (Prosopis Glandulosa). • All tree specimens will be a minimum 24-inch box size at the time of planting and have low water use. Shrubs/Accents/Groundcover • Low Water Usage: Desert Carpet, Parry’s Agave, Baccharis, Dwarf Bottlebrush, Century Plant, Octopus Agave, Centennial Baccharis, Damianita, Bat-Face Cuphea, Sierra Gold Dalea, Black Prairie Clover, Trailing Indigo Bush, Grey Desert Spoon, Brittle Bush, Red Yucca, Cimmeron, Blackfoot Daisy, Wild Petunia, Chaparral Yucca. • Medium Water Usage: Trailing Lantana, Autumn Sage, Esperanza Yellowbells, Wedelia. • All shrubs and plants will be a minimum five-gallon (5) size at the time of planting. • Cimmeron and Esperanza Yellow Bells are used for screening and placed between the face of the wall and adjacent to the public street. Hardscape • Primary ground cover: 3/8-inch Tan Decomposed Granite (Palm Springs Gold) • Accent: Rock Mulch – 1.5-inch to 3-inch round river rock mulch. • Boulders (16 total) ranging from three (3) feet to four (4) feet in diameter. Live plantings are located along the perimeter street frontages. The plan identifies the landscape area will use a drip irrigation system. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 8 of 12 Figure 4 – Project Landscape Plan Analysis: Land Use Compatibility The project is consistent with the Palm Desert General Plan goals and policies of the Land Use Element. The project site is designated Employment District (ED) by the Palm Desert General Plan Land Use Element (see page 31 of the General Plan). The ED designation is intended to provide a wide variety of office, and limited commercial activity, including uses such as medical offices, traditional business parks, and some light industrial and manufacturing uses. The project is compatible with the development pattern within the surrounding area by proposing expansions to a used auto sales facility. The areas to the east of the site are generally industrial and developed with a mix of light industrial and office buildings. The areas to the south and west of the project site are developed with commercial and retail land uses. The adjacent Monterey Crossings Specific Plan to the west allows for future auto sales uses. The project provides an appropriate transition between retail-oriented commercial uses and service industrial and employment land uses while providing an attractive frontage design. The proposal implements the design goals and policies of the General Plan including: Land Use Policy 2.9 – Preserves continuous sidewalk areas along high-volume traffic corridors, minimizing vehicle intrusions across sidewalks, and screens parking areas by installing landscaping and a continuous block wall for the vehicle sales storage area. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 9 of 12 Land Use Policy 2.10 – The existing area is auto-oriented and located in an auto-oriented area due to its proximity to the Interstate 10 freeway. Land Use Policy 3.16 – The proposed use and building provides an appropriate transition between Employment land use areas and Regional Retail Land Use Designation. Development Standards The project site is zoned Service Industrial (SI) and allows the development of outdoor auto sales as a conditionally permitted use with the approval of a PP and CUP by the Palm Desert Planning Commission in accordance with Palm Desert Municipal Code Section (PDMC) 25.72.030. The existing CarMax facility was approved subject to a PP and CUP, and the proposed expansion will require the Planning Commission’s approval of an amendment. Development in the SI zone is subject to development standards provided under PDMC 25.16.50. Figure 5 summarizes the project’s conformance analysis for the new additions: Figure 5 – Project Conformance Summary STANDARD SI PROJECT CONFORMS Lot Size, Min. 20,000 square feet 267,023 square feet Yes Front Yard Setback 20’-0” 84.17’ Yes Side Yard Setback 0’-0” 215.98’ N/A Street Side Yard Setback 10’-0” N/A Yes Rear Yard Setback 0’-0” 44.06’ Yes Floor Area Ratio 0.75 0.037 Yes Maximum Height 40’-0” 21’-0” Yes Maximum No. of Stories 3 Stories 1 Story Yes Parking 15 Spaces 55 Additional Spaces Yes Parking Section 25.46.040 Parking Requirements of the PDMC establishes that auto and vehicle sales uses are required to provide a minimum of two (2) parking spaces per 1,000 square feet of building area. The building will add 2,351 of building area devoted to sales use; therefore, requires an additional five (5) parking spaces. The carwash will require a minimum of three (3) spaces. The existing parking lot provides 60 spaces, and the project will add 40 more spaces for a total of 100 parking spaces. The project exceeds the minimum parking requirements. Public Input: Public Notification Public noticing was conducted for the January 17, 2023, Planning Commission meeting per the requirements of PDMC Section 25.60.060 and Government Code Sections 65090 to 65094. A public hearing notice was published a minimum of 10 days before the hearing City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 10 of 12 date on Friday, November 25, 2022, in The Desert Sun newspaper. Notices were mailed to all property owners within 300 feet of the project site. PDMC Section 25.60.160 requires all development projects on sites greater than five (5) acres to prepare Community Engagement Plans to present and engage in a public outreach meeting early in the entitlement process of new projects and address concerns of the public prior to an action of the approving body. The proposal is located on a site that is 2.17 acres; therefore, no community engagement plan is required. Environmental Assessment/Environment Review: Staff recommends that the Planning Commission finds that the project is exempt from CEQA per Section 15332 of the CEQA guidelines as the project is a Class 32 Exemption for “Infill” development. Class 32 is intended for projects characterized as infill developments satisfies the conditions described below: 1) The project is consistent with the applicable General Plan designation and all applicable General Plan policies. As analyzed, the project includes an additional 2,351-square-foot addition to a retail sales building, a 923-square-foot carwash building, and an expansion of parking areas. The proposed project complies with the development standards within the SI zoning designation. 2) The project occurs on a 2.17-acre portion of the project site, which is less than five (5) acres specified in the criteria of the Class 32 exemption and is substantially surrounded by urban uses. 3) The site has no value as a habitat for endangered, rare, or threatened species. The site has been previously graded and is occupied by existing portable building structures and a greenhouse. The site is not identified as a suitable habitat for endangered species in the Coachella Valley Multi-Species Habitat Conservation Plan (MSHCP). 4) Additionally, approval of the project would not result in any significant effects relating to traffic, noise, air quality, or water quality. The proposed use will not result in significant noise that will violate the City’s Noise Ordinance. In addition, the City Engineer has reviewed the proposed use and the existing infrastructure, including the off-site improvements, and staff finds the use will not have a significant effect on traffic. The applicant has provided a Traffic Impact Assessment Letter identifying that the project expansion will generate up to two (2) trips produced at a.m. peak hours and 16 trips produced at p.m. peak hours, increasing the project total to 96 per day. No intersections within the area of the project site will be impacted by the additional trips. This project will not adversely impact the surrounding traffic system per the County of Riverside Analysis Guidelines for Level of Service and Vehicle Miles Traveled adopted in December 2020 (TIA Guidelines), which are adopted by reference by the City of Palm Desert for the purpose of traffic review. The TIA guidelines indicate that projects that generate less than 100 peak-hour trips typically do not affect the level of service (LOS). Additionally, the TIA guidelines indicate that the mini-storage yards City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 11 of 12 (personal storage) are an activity that will not require a TIA. In addition, a preliminary grading plan and hydrology report have been submitted for review, and final approval will commence as part of the conditions of approval herein. No other significant noise or air quality effects were identified for the project. 5) Finally, the site can be adequately served by all required utilities and public services. The proposed project has been reviewed by various utility agencies and public services, including Southern California Edison, the Coachella Valley Water District, and Burrtec Waste Management. These agencies have not identified that utilities in the area are insufficient to serve the proposed office building and parking area. Additionally, the project is not subject to any of the exceptions for categorical exemptions identified in CEQA Guidelines Section 15300.2: 1) The project qualifies as a Class 32 exemption, which is not listed as one of the classes under 15300.2 (A). The project is not located on a site where it may have an adverse impact on an environmental resource of hazardous or critical concern where designated, precisely mapped, and officially adopted pursuant to law by federal, state, or local agencies. The project site will not impact designated environmental or biological resources as it is not located within a conservation area as identified by the Coachella Valley Multiple Species Habitat Conservation Plan. 2) The project will not have a cumulative impact on the environment. The proposal does not conflict with additional impacts in terms of traffic generation. The proposal will expand existing parking areas and construct new admin and storage buildings that replace existing portable buildings used for the same functions. As indicated by the traffic impact assessment prepared for the project, no significant traffic impacts are anticipated. 3) There are no unusual circumstances on the project site. The project site is not located within a flood zone per the latest FEMA Flood Zone Maps. The project site is located within an Urban area per Fire Hazard Severity Zone maps available from the Riverside County Fire Department and depicted in Figure 8.5 on Page 119 of the General Plan. The project site is not identified within an Alquist-Priolo Fault Zone per the latest maps on file with the California Department of Conservation; the nearest fault zone is the San Andreas Fault located north of the Palm Desert City Limits. 4) The project site is not located in proximity to any scenic highway. The nearest officially designated scenic highway is Highway 74, located outside of the Palm Desert City Limits approximately 5.6 miles to the south of the project site. 5) The project site is identified as a historic waste site on any list compiled per Section 65962.5 of the Government Code. 6) The project site does not contain any existing designated historic resource and is not within a designated historic preservation district. The site is vacant. City of Palm Desert Case Nos. PP/CUP17-059 Amendment No. 1/EA22-0007 Page 12 of 12 Findings of Approval: Findings can be made in support of the project under the City’s Municipal Code. Findings in support of this project are contained in Planning Commission Resolution No. 2827, attached to this staff report. REVIEWED BY: Department Director: Rosie Lua (for Richard Cannone, AICP) Deputy Director: Rosie Lua ATTACHMENTS: 1. Draft Planning Commission Resolution No. 2827 2. Public Hearing Notice 3. Notification Radius 4. Planning Commission Resolution No. 2707 5. Architecture Review Notice of Action and Minutes 6. Project Traffic Analysis Letter 7. Preliminary Hydrology Plan 8. Preliminary WQMP 9. Project Plans PLANNING COMMISSION RESOLUTION NO. 2827 A RESOLUTION OF THE PLANNING COMMISSION OF THE CITY OF PALM DESERT, CALIFORNIA, ADOPTING A NOTICE OF EXEMPTION PURSUANT TO THE STATE OF CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA); AND APPROVING AN AMENDMENT TO A PRECISE PLAN, CONDITIONAL USE PERMIT, AND AN ENVIRONMENTAL ASSESSMENT TO EXPAND AN EXISTING CARMAX OUTDOOR AUTOMOTIVE SALES FACILITY BY CONSTRUCTING A BUILDING ADDITION TO AN EXISTING SALES BUILDING, NEW PRIVATE CARWASH TUNNEL, EXPANSION OF AN EXISTING CUSTOMER PARKING LOT, AND CONSTRUCTION OF A NEW SALES STAGING AREA AT 73450 DINAH SHORE DRIVE CASE NOS. PP/CUP 17-059 Amendment No.1/EA 22-0007 WHEREAS, the Planning Commission of the City of Palm Desert, California, did on the 1st day of August 2017, adopt Resolution No. 2703, approving the original development of the CarMax outdoor automotive sales facility (PP/CUP 17-059) located at 73450 Dinah Shore Drive (Project site); and WHEREAS, Michael Baker International (“Applicant”), submitted applications for a Precise Plan (PP), Conditional Use Permit (CUP) amendment, and an Environmental Assessment (EA) for the expansion of an existing CarMax outdoor automotive sales facility, including expansion of an existing sales/auto service building, construction of a new private carwash building for service of on-site vehicles, expansion to the existing parking lot for customers and employees, and construction of a new sales staging area on a 2.17-acre portion of the site at 73450 Dinah Shore Drive (“Project”); and WHEREAS, the Project site is designated as Employment District (ED) by the Land Use Element of the Palm Desert General Plan adopted on November 10, 2016, and the Project is consistent with the development intensity and use characteristics considered by the Palm Desert General Plan for the ED land use designation; and WHEREAS, the Project site has a zoning designation of Service Industrial (SI allowing “Automotive Sales Outdoor” as an allowed land use, subject to the approval of a CUP; and WHEREAS, the Project conforms to the development standards in the City’s Zoning Ordinance for the SI zoning district and other applicable requirements; and WHEREAS, the Architectural Review Commission (ARC) of the City of Palm Desert, California, did on the 13th day of December 2022, approve a design review for the Project, subject to conditions; and WHEREAS, under Section 21067 of the Public Resources Code, Section 15367 of the State CEQA Guidelines (Cal. Code Regs., tit. 14, § 15000 et seq.), and the City of Palm Desert’s (“City’s”) Local CEQA Guidelines, the City is the lead agency for the Project; and WHEREAS, the Project has complied with the requirements of the "City of Palm Desert Procedure for Implementation of CEQA” Resolution No. 2019-41, determining that PLANNING COMMISSION RESOLUTION NO. 2827 2 the project is categorically exempt under Section 15332 In-fill Development (Class 32) of the CEQA Guidelines; and WHEREAS, the Planning Commission of the City of Palm Desert, California, did on the 17th day of January 2023, hold a duly noticed public hearing to consider the request by the Applicant for approval of the above-noted Project request, subject to conditions; and WHEREAS, all other legal prerequisites to the adoption of this Resolution have occurred; and WHEREAS, at the said public hearing, upon hearing and considering all testimony and arguments, if any, of all interested persons desiring to be heard, the Planning Commission did find the following facts and reasons, which are outlined in the staff report, exist to justify approval of said request: NOW, THEREFORE, BE IT RESOLVED by the Planning Commission of the City of Palm Desert, California, as follows: SECTION 1. Recitals. The Planning Commission hereby finds that the foregoing recitals are true and correct and are incorporated herein as substantive findings of this Resolution. SECTION 2. Findings on Conditional Use Permit. Under PDMC Section 25.72.050(F), the findings for the tentative map are the following: 1. That the proposed location of the conditional use is in accord with the objectives of this title and the purpose of the district in which the site is located. The project is located within a property designated SI. The purpose and character of the SI zone is to allow for the manufacturing, distribution, research and development, and service of products intended for use within Palm Desert and surrounding communities. The SI zone permits “Automotive Sales (Outdoor)” subject to the approval of a CUP. In August 2017, the Palm Desert Planning Commission adopted Resolution No. 2703, approving the original development of the CarMax outdoor automotive sales facility. The proposal will expand this existing use by providing additional sales building areas, outdoor vehicle storage areas, a carwash tunnel to service vehicle inventory, and parking to support the use. The use is allowed by the zoning ordinance and is consistent with the intent and purpose of the SI zone. 2. That the proposed location of the conditional use and the conditions under which it would be operated or maintained will not be detrimental to the public health, safety, or welfare or be materially injurious to properties or improvements in the vicinity. The site is physically suitable for the proposed outdoor automotive sales facility expansion. The site has suitable access, grading, drainage, and zoning to allow the proposed development. The Project is not located within a hazardous area that would be subject to flooding, liquefaction, landslide, fault zones, or other natural PLANNING COMMISSION RESOLUTION NO. 2827 3 hazards. The project does not generate adverse effects that would cause public health problems. Ground-disturbing activities are conditioned to prepare plans to control fugitive dust. The project includes a traffic analysis, and it is anticipated the project will not generate traffic demand or congestion in the area. The proposed project includes hard surface pedestrian pathways and connections from the public right-of-way to ensure walkability throughout. All engineering documents, including the preliminary grading plan and Water Quality Management Plan (WQMP), are under review to ensure the design of the project incorporates the proper improvements, including adequately sized retention basins for onsite drainage. In addition, the overall building design ensures the protection of public health, safety, and general welfare. The use will not create a public nuisance in terms of parking shortages, or traffic congestion as a result of excess trip generation and will meet all applicable requirements of the building code. Therefore, the project will not be detrimental to public health, safety, or welfare or be materially injurious to properties or improvements in the project vicinity. 3. That the proposed conditional use will comply with each of the applicable provisions of this title, except for approved variances or adjustments. The proposed development complies with all setbacks (front, rear, and side yards), Floor Area Ratio (FAR), landscape coverage, and parking requirements of the SI zone. The request does not include any variances or adjustments. 4. That the proposed conditional use complies with the goals, objectives, and policies of the City’s General Plan. The site is physically suitable for the proposed density of development. The allowable density for the site has been evaluated by the General Plan. The Applicant has prepared the appropriate technical studies to assess that the site is physically suitable to develop. The project is compatible with the existing development pattern within the surrounding area and with the zoning designations for the surrounding vacant sites. The property is designated Employment District by the General Plan. Land Use Policy 2.9 – Preserves continuous sidewalk areas along high-volume traffic corridors, minimizing vehicle intrusions across sidewalks, and screens parking areas by installing landscaping and a continuous block wall for the vehicle sales storage area. Land Use Policy 2.10 – Auto-oriented uses. This policy recommends allowing automobile-oriented business in places that are clearly automobile-oriented, ensuring that such uses do not disrupt the pedestrian flow, are not concentrated, do not break up the building mass of the streetscape, and are compatible with the planned uses of the area. The Project is located near the Monterey Avenue/Interstation-10 freeway interchange, which is clearly automobile-oriented and will be compatible with the surrounding land uses, which include commercial and light industrial buildings. PLANNING COMMISSION RESOLUTION NO. 2827 4 Land Use Policy 3.16 – The Project and building provides an appropriate transition between Employment land use areas and Regional Retail Land Use Designation. Land Use Policy 9.3 – Diverse tax base. This policy recommends the development is guided to maintain a fiscally sound city with a sustainable tax base. The Project provides an expansion to the existing auto sales facility, which will serve as a point of sale for the collection of sales tax for the City. SECTION 3. CEQA. The application has complied with the requirements of the “City of Palm Desert Procedure for Implementation of CEQA” Resolution No. 2019-41, in that the Planning Commission finds that the Project is exempt from CEQA per Section 15332 of the CEQA guidelines as the Project is a Class 32 Exemption for Infill” development. Class 32 is intended for projects characterized as infill developments satisfies the conditions described below: 1) The Project is consistent with the applicable General Plan designation and all applicable General Plan policies. As analyzed, the Project includes an additional 2,351-square-foot addition to a retail sales building, a 923-square-foot carwash building, and an expansion of parking areas. The proposed Project complies with the development standards within the SI zoning designation. 2) The Project occurs on a 2.17-acre portion of the project site, which is less than five (5) acres specified in the criteria of the Class 32 exemption and is substantially surrounded by urban uses. 3) The site has no value as a habitat for endangered, rare, or threatened species. The site has been previously graded and is occupied by existing portable building structures and a greenhouse. The site is not identified as a suitable habitat for endangered species in the Coachella Valley Multi-Species Habitat Conservation Plan (MSHCP). 4) Additionally, approval of the Project would not result in any significant effects relating to traffic, noise, air quality, or water quality. The proposed use will not result in significant noise that will violate the City’s Noise Ordinance. In addition, the City Engineer has reviewed the proposed use and the existing infrastructure, including the off-site improvements, and staff finds the use will not have a significant effect on traffic. The Applicant has provided a Traffic Impact Assessment Letter identifying that the project expansion will generate up to two (2) trips produced at a.m. peak hours and 16 trips produced at p.m. peak hours, increasing the project total to 96 per day. No intersections within the area of the Project site will be impacted by the additional trips. This Project will not adversely impact the surrounding traffic system per the County of Riverside Analysis Guidelines for Level of Service and Vehicle Miles Traveled adopted in December 2020 (TIA Guidelines), which are adopted by reference by the City of Palm Desert for the purpose of traffic review. The TIA guidelines indicate that projects that generate less than 100 peak-hour trips typically do not affect the level PLANNING COMMISSION RESOLUTION NO. 2827 5 of service (LOS). Additionally, the TIA guidelines indicate that the mini-storage yards (personal storage) are an activity that will not require a TIA. In addition, a preliminary grading plan and hydrology report have been submitted for review, and final approval will commence as part of the conditions of approval herein. No other significant noise or air quality effects were identified for the project. 5) Finally, the site can be adequately served by all required utilities and public services. The proposed Project has been reviewed by various utility agencies and public services, including Southern California Edison, the Coachella Valley Water District, and Burrtec Waste Management. These agencies have not identified that utilities in the area are insufficient to serve the proposed office building and parking area. Additionally, the Project is not subject to any of the exceptions for categorical exemptions identified in CEQA Guidelines Section 15300.2: 1) The Project qualifies as a Class 32 exemption, which is not listed as one of the classes under 15300.2 (A). The Project is not located on a site where it may have an adverse impact on an environmental resource of hazardous or critical concern where designated, precisely mapped, and officially adopted pursuant to law by federal, state, or local agencies. The Project site will not impact designated environmental or biological resources as it is not located within a conservation area as identified by the (MSHCP). 2) The Project will not have a cumulative impact on the environment. The proposal does not conflict with additional impacts in terms of traffic generation. The proposal will expand existing parking areas and construct new admin and storage buildings that replace existing portable buildings used for the same functions. As indicated by the traffic impact assessment prepared for the project, no significant traffic impacts are anticipated. 3) There are no unusual circumstances on the Project site. The Project site is not located within a flood zone per the latest FEMA Flood Zone Maps. The Project site is located within an urban area per Fire Hazard Severity Zone maps available from the Riverside County Fire Department and depicted in Figure 8.5 on Page 119 of the General Plan. The project site is not identified within an Alquist-Priolo Fault Zone per the latest maps on file with the California Department of Conservation; the nearest fault zone is the San Andreas Fault located north of the Palm Desert City Limits. 4) The Project site is not located in proximity to any scenic highway. The nearest officially designated scenic highway is Highway 74, located outside of the Palm Desert City Limits approximately 5.6 miles to the south of the Project site. 5) The Project site is identified as a historic waste site on any list compiled per Section 65962.5 of the Government Code. PLANNING COMMISSION RESOLUTION NO. 2827 6 6) The Project site does not contain any existing designated historic resource and is not within a designated historic preservation district. The site was previously developed as an auto sales facility in 2018 and contains no historical value. SECTION 4. Project Approval. The Planning Commission approves PP/CUP17-059 Amendment No. 1 and EA22-0007; and SECTION 5. Approval. The Planning Commission approves and adopts the Project, subject to the Conditions of Approval attached hereto as Exhibit “A.” ADOPTED ON January 17, 2023 NANCY DE LUNA CHAIRPERSON ATTEST: RICHARD D. CANNONE, AICP SECRETARY PLANNING COMMISSION RESOLUTION NO. 2827 7 I, Richard D. Cannone, AICP, Secretary of the City of Palm Desert, hereby certify that Resolution No. 2827 is a full, true, and correct copy, and was duly adopted at a regular meeting of the Planning Commission of the City of Palm Desert on January 17, 2023, by the following vote: AYES: NOES: ABSENT: ABSTAIN: RECUSED: IN WITNESS WHEREOF, I have hereunto set my hand and affixed the official seal of the City of Palm Desert, California, on January____, 2023. RICHARD D. CANNONE, AICP SECRETARY PLANNING COMMISSION RESOLUTION NO. 2827 8 EXHIBIT “A’ CONDITIONS OF APPROVAL CASE NOS. PP/CUP17-059 AMENDMENT NO. 1/EA22-0007 PLANNING DIVISION: 1. The development of the property shall conform substantially with exhibits on file with the Development Services Department, except as modified by the following conditions. Any variation from the approved plans must be reviewed and approved by the Planning Division prior to building permit issuance and may require review and approval by the ARC, Planning Commission, and/or City Council. 2. The Applicant agrees that in the event of any administrative, legal, or equitable action instituted by a third party challenging the validity of any of the procedures leading to the adoption of these Project Approvals for the Project, or the Project Approvals themselves, the Developer and City each shall have the right, in their sole discretion, to elect whether or not to defend such action. The Developer, at its sole expense, shall defend, indemnify, and hold harmless the City (including its agents, officers, and employees) from any such action, claim, or proceeding with counsel chosen by the City, subject to the Developer’s approval of counsel, which shall not be unreasonably denied, and at the Developer’s sole expense. If the City is aware of such an action or proceeding, it shall promptly notify the Developer and cooperate in the defense. The Developer, upon such notification, shall deposit with City sufficient funds in the judgment of the City Finance Director to cover the expense of defending such action without any offset or claim against said deposit to assure that the City expends no City funds. If both Parties elect to defend, the Parties hereby agree to affirmatively cooperate in defending said action and to execute a joint defense and confidentiality agreement in order to share and protect the information under the joint defense privilege recognized under applicable law. As part of the cooperation in defending an action, City and Developer shall coordinate their defense in order to make the most efficient use of legal counsel and to share and protect information. Developer and City shall each have sole discretion to terminate its defense at any time. The City shall not settle any third-party litigation of Project approvals without the Developer’s consent, which consent shall not be unreasonably withheld, conditioned, or delayed unless the Developer materially breaches this indemnification requirement. 3. The development of the property described herein shall be subject to the restrictions and limitations set forth herein, which are in addition to the approved development standards listed in the PDMC, and state and federal statutes now in force, or which hereafter may be in force. 4. The PP shall expire if construction of the said Project shall not commence within 24 months from the date of final approval unless an extension of time is granted by the Palm Desert Planning Commission; otherwise, said approval shall become null, void, and of no effect whatsoever. PLANNING COMMISSION RESOLUTION NO. 2827 9 5. The PP and Conditional Use Permit Approval is for the expansion of an existing outdoor automotive sales facility, including expansion of an existing sales/auto service building, construction of a new private carwash building for service of onsite vehicles, expansion to the existing parking lot for customers and employees, and construction of a new sales staging area and related landscape, constructed in a single-phase. 6. The approved PP shall only be modified with written City approval per PDMC Chapter 25.72.030. Any proposed changes to this PP will require an amendment to the application, which may result in a new public hearing. 7. All construction documentation shall be coordinated for consistency, including, but not limited to, architectural, structural, mechanical, electrical, plumbing, landscape and irrigation, grading, and street improvement plans. All such plans shall be consistent with the approved entitlement plans on file with the Development Services Department. 8. The Applicant shall execute a written acknowledgment to the Planning Division stating acceptance of and compliance with all the Conditions of Approval of Resolution No. 2827 for PP/CUP17-059 Amendment No. 1/EA22-0007 and that the plans submitted are in compliance with the Conditions of Approval. No modifications shall be made to said plans without written approval from the appropriate decision-making body. 9. All conditions of Planning Commission Resolution No. 2703 shall remain in effect except as modified herein. 10. Prior to the issuance of a building permit for construction of any use or structure contemplated by this approval, the Applicant shall first obtain permits and or clearance from the following agencies: Coachella Valley Water District (CVWD) Public Works Department Fire Department Building and Safety Division Evidence of said permit or clearance from the above agencies shall be presented to the Building & Safety Division at the time of issuance of a building permit for the use contemplated herewith. 11. This Project is subject to payment of the City’s Public Art fee. The fee will be applied prior to a building permit issuance and shall remain in the City’s public art fund. 12. All exterior lighting sources shall be fully shielded and directed downwards and is subject to approval by the Development Services Department. Luminaries with total lamp lumens above 16,000 lumens shall not be used. Prior to building permit issuance, the Applicant shall submit plans for outdoor lighting as required by PDMC Section 24.16.030 and include glare ratings and color temperature for all exterior light fixtures. PLANNING COMMISSION RESOLUTION NO. 2827 10 13. Final lighting plans shall be submitted per PDMC Section 24.16 for any landscape, architectural, street, or other lighting types within the Project area. 14. Prior to the building permit issuance, the Applicant shall submit a landscape construction application for approval by the Development Services Department and Coachella Valley Water District. 15. Final landscape and irrigation documents shall be prepared by a landscape architect registered with the State of California and shall be submitted to the Development Services Department and the CVWD for review and approval. All sheets shall be signed by the landscape architect and shall include the license number and the expiration date. The landscape plan shall conform to the preliminary landscape plans prepared as part of this application and shall include dense plantings of live landscape material. All plants shall be a minimum of five (5) gallons in size, and all trees shall be a minimum 24-inch box in size. A. The Applicant shall submit final landscape construction plans to the Palm Desert Development Services Department for review and acceptance prior to submittal to CVWD. 16. All Project irrigation systems shall function properly, and landscaping shall be maintained in a healthy and thriving condition. The maintenance of landscaping and the irrigation system shall be permanently provided for all areas of the Project site. Furthermore, the plans shall identify responsibility for the continued maintenance. 17. Prior to the issuance of the Certificate of Occupancy, the Project shall record a landscape maintenance agreement for all landscaping located within the public right-of- way. 18. Prior to the issuance of the Certificate of Occupancy, the Project landscape architect shall submit written verification to the Planning Division that the landscaping and irrigation have been installed per the approved landscape plan. 19. All exterior and rooftop equipment and all appurtenances thereto shall be completely screened from public view by walls or roof screens that are architecturally treated to be consistent with the building. The final construction plans shall include appropriate drawings demonstrating how such equipment is to be screened from view. 20. All roof drainage systems and devices shall be designed such that they are fully screened from view from all public streets. Drainage devices, including but not limited to down-spouts, shall not be located on any street-facing building elevation or area that is clearly visible from the public right-of-way. Drainage devices shall be fully integrated into the building structure and located within the exterior walls of the structure. 21. All roof access ladders shall be located on the inside of the building and shall be fully screened by rooftop parapets. PLANNING COMMISSION RESOLUTION NO. 2827 11 22. All ground-mounted utility structures including, but not limited to, transformers, HVAC equipment, and backflow prevention valves shall be located out of view from any public street or adequately screened using landscaping and/or masonry walls. 23. Exterior building elevations showing building wall materials, roof types, exterior colors, and appropriate vertical dimensions shall be included in the development construction drawings. 24. All parking spaces shall be clearly marked with white or yellow paint or other easily distinguished material. Except as required by the state and the Americans with Disability Act (ADA) requirements, all markings shall be a minimum four-inch (4”) wide double (“hairpin” style) stripe designed to provide 18 inches measured outside to outside under City Council Resolution No. 01-5. 25. The Applicant shall provide a minimum of 55 additional on-site parking spaces for customers and employees. 26. The Applicant or any successor in interest shall comply with all applicable local, state, and federal laws and regulations. 27. A copy of the herein-listed Conditions of Approval shall be included in the construction documentation package for the Project, which shall be continuously maintained on-site during Project construction. 28. Exterior signage shall comply with Chapter 25.56 of the PDMC at all times. 29. Prior to a permit issuance, the Applicant shall submit plans for the final design of all site fences and walls subject to review and approval by the Palm Desert Development Services Department. The design of the walls shall be consistent with the height, material, and design (tan split-face masonry block, pilasters spaced no less than 30’-0” apart on the perimeter of the sales lot area, and 2” cap) on the approved conceptual site plan dated November 17, 2022. 30. The outdoor vehicle sales staging area shall be enclosed on four (4) sides by a minimum six-foot-high (6’) masonry block wall and paved. The wall, paving, and landscaped perimeter of the sales staging area shall be constructed prior to the storage of vehicles. A. Use of the outdoor vehicles sales area shall be limited to vehicle storage. B. Storage of equipment related to vehicle servicing shall not exceed the height of the perimeter wall. Temporary storage which exceeds the height of the perimeter wall shall be subject to the approval of a Temporary Use Permit (TUP) by the Director of Development Services. C. Additional outdoor storage may be approved by the Director of Development Services subject to screening, landscaping, lighting, and parking requirements. PLANNING COMMISSION RESOLUTION NO. 2827 12 31. Future modifications to site walls or fences shall require approval by the Director of Development Services. The use of barbed wire, razor wire, and spiked pickets for fencing is prohibited. 32. Site fences and walls shall be maintained at all times. Graffiti shall be removed by the applicant upon discovery. 33. The approved hours of operation for the facility shall be: A. Showroom: Monday-Friday 10:00 a.m. to 9:00 p.m., and Sunday 12:00 p.m. to 7:00 p.m. B. Service: Monday-Friday: 7:30 a.m. to 6:00 p.m. 34. All exterior lighting shall be on an automated timer and be dimmed after operational hours to reflect the approved Non-Operational Hours Photometric Site Plan dated October 17, 2022. 35. Sufficient space shall be provided on-site for service drop-offs to prevent stacking of vehicles onto a public street at all times. 36. The carwash shall be used for washing inventory vehicles only. Use by the public shall be prohibited at all times. 37. The Applicant shall construct the pedestrian circulation network as shown on the approved preliminary site plan and provide pedestrian access points adjacent to all vehicular driveways as shown on the approved preliminary site plan. 38. The Applicant shall provide payment for filing fees for the Notice of Exemption within five (5) days of project approval. 39. Prior to permit issuance, the final construction drawings for the auto sales facility, landscaping, and carwash shall return to the Architecture Review Commission to verify the final drawings substantially conform to the preliminary plan set. 40. The Applicant shall comply with the recommendations made by the City’s Architectural Review Commission (ARC), as referenced in the December 13, 2022, Notice of Action. LAND DEVELOPMENT DIVISION/PUBLIC WORKS DEPARTMENT: 41. The following plans, studies, and exhibits are hereby referenced: CarMax Auto Superstore No. 6113 Site Plan, prepared by Michael Baker International and dated November 10, 2022. 42. It is assumed that easements shown on the conceptual grading exhibit are shown correctly and includes all the easements that encumber the subject property. A current preliminary title report for the site will be required to be submitted during the technical plan review. The Applicant shall secure approval from all, if any, easement holders for PLANNING COMMISSION RESOLUTION NO. 2827 13 all grading and improvements, which are proposed over the respective easement or provide evidence that the easement has been relocated, quitclaimed, vacated, abandoned, easement holder cannot be found, or is otherwise of no effect. Should such approvals or alternate actions regarding the easements not be provided and approved by the City, the Applicant may be required to amend or revise the proposed site configuration as may be necessary. 43. It is understood that the conceptual exhibits correctly show acceptable centerline elevations, all existing easements, traveled ways, and drainage courses with appropriate Q’s and that the omission or unacceptability may require that the Applicant amend or revise the site plan as may be. 44. The Applicant shall pay all appropriate signalization fees prior to the issuance of the first building permit for the development in accordance with the City’s Resolution No. 79-17 and 79-55. 45. Prior to map approval, the Applicant shall pay all, appropriate drainage fees in accordance with the City’s Municipal Code Section 26.49 and Palm Desert Ordinance No. 653. 46. The Applicant shall comply with Palm Desert Ordinance No. 843, Section 24.20 Stormwater Management and Discharge Ordinance. 47. All utility extensions within the site shall be placed underground unless otherwise specified or allowed by the respective utility purveyor. 48. Prior to a grading permit, the Applicant shall prepare a final grading plan for the site. No grading or other improvements shall be permitted until a final grading plan has been approved by the City Engineer. Grading plans and all grading shall conform to the approved Conceptual Grading Plan, the California Building Code, PDMC Title 27 Grading, and all other relevant laws, rules, and regulations governing grading in the City of Palm Desert. 49. The grading plan shall provide for acceptance and proper disposal of all off-site drainage flowing onto or through the site. Should the quantities exceed the street capacity, the Applicant shall provide adequate drainage facilities and/or appropriate easements as approved by the City Engineer. 50. Pad elevations, as shown on the conceptual exhibit, are subject to review and modification per Chapter 27 of the PDMC. 51. Prior to approval of the grading plan, the Applicant shall prepare a detailed final flood hazard/hydrology and hydraulics report for approval of the City Engineer. 52. All drainage and storm drain improvements shall be designed per PDMC Title 24, Riverside County Flood Control and Water Conservation District’s standards for the Drainage Element of the Palm Desert General Plan, and all other relevant laws, rules, and regulations governing grading in the City of Palm Desert. PLANNING COMMISSION RESOLUTION NO. 2827 14 53. Prior to the issuance of a grading permit, the Applicant shall submit a PM10 application for review and approval. The Applicant shall comply with all provisions of PDMC Section 24.12 regarding Fugitive Dust Control. 54. Where grading involves import or export, the Applicant shall obtain permits, from the Public Works Department, including import/export quantities and hauling route. 55. Prior to a grading permit, it shall be the sole responsibility of the Applicant to obtain any and all proposed or required easements and/or permissions necessary to perform the grading shown on the grading plan exhibit. Proof shall be provided to the Land Development Division prior to the issuance of a grading permit. 56. It is assumed that the grading and the provisions for water quality management shown on the conceptual grading exhibit can comply with all requirements for a Final Water Quality Management Plan (F-WQMP) without substantial change from that shown. Prior to approval of the grading plan, the landowner shall prepare, or cause to be prepared, a Final WQMP in conformance with the requirements of the Riverside County Flood Control and Water Conservation District (RCFC&WCD) Whitewater River Watershed area for approval of the City Engineer. 57. This Project is part of a special assessment district known as Section 29, runoff from the site is anticipated to discharge into the City’s Section 29 water quality basin. 58. All post-construction BMPs shall be designed based on the City of Palm Desert’s maximum infiltration criteria of one (1) inch/hour. 59. Prior to the issuance of a grading permit, the Applicant shall submit a signed and notarized WQMP Operations and Maintenance Agreement to the City. The agreement shall provide for the maintenance and operation of trash disposal areas and water- quality BMP facilities by the property owner. 60. Prior to the issuance of a grading permit and in compliance with the City of Palm Desert Municipal Code Chapter 27.24, the Applicant shall enter into an agreement and post financial security guarantee for all grading work related to this Project. 61. Prior to the issuance of a grading permit for each PP, the Applicant shall submit for review and approval of the City Engineer a final Geotechnical Report that includes project-specific recommendations. 62. Prior to the start of grading activities, the Applicant shall install all erosion and dust control mechanisms for the site as approved by the City. 63. Upon completion of grading of each PP, the Project’s Geotechnical Engineer shall certify to the completion of grading in conformance with the approved grading plans and the recommendations of the geotechnical report approved for this Project. A licensed land surveyor shall certify to the completion of grading in conformance with the lines and grades shown on the approved grading plans. PLANNING COMMISSION RESOLUTION NO. 2827 15 64. Prior to a grading permit, the Applicant shall submit improvement plans for all public improvements. Non-standard encroachments into the proposed public right-of-way will not be permitted unless clearly identified on these Conditions of Approval. 65. Prior to a building permit, the Applicant shall submit for review and approval of the City Engineer a parcel map waiver application to merge lots within the boundary of the project, APNs 694-060-034 and 694-060-036. 66. Prior to the Certificate of Occupancy, the Applicant is responsible for the construction and installation of improvements on Dinah Shore Drive, as approved by the City Engineer and in compliance with the City’s General Plan and standard specifications. Improvements generally include, but are not limited to: A. landscape and irrigation improvements along the site boundary and transitioning to existing improvements to the east and west of the site. B. A Class II bicycle lane in accordance with Coachella Valley Association of Governments Active Transportation Planning (CVAG ATP) Design Guidelines Section 5.3. C. The Applicant shall show, as reference only, all existing and proposed utility connections. Utility plans shall be processed and approved by CVWD. 67. Prior to the issuance of an encroachment permit for public improvements, the Applicant shall enter into an agreement and post financial security guarantee for the construction of all off-site/public improvements in accordance with Chapter 27.24 of the PDMC. The form and amount of the financial security shall be reviewed and approved by the City Engineer. The Applicant shall guarantee all improvements for a period of one year from the date of final acceptance and the improvement guarantee shall be backed by a bond or cash deposit in the amount of ten percent of the surety posted for the improvements. 68. Prior to a building final inspection, the Applicant is responsible for the completion of construction of all grading and improvements for which plans are required. 69. Prior to the final building permit inspection or Certificate of Occupancy, the Applicant is responsible for the completion of all public improvements. BUILDING AND SAFETY DIVISION: 70. This project shall comply with the latest adopted edition of the following codes: A. California Building Code and its appendices and standards. B. California Commercial Code and its appendices and standards. C. California Plumbing Code and its appendices and standards. D. California Mechanical Code and its appendices and standards. E. California Electrical Code. F. California Energy Code. G. California Green Building Standards Code. H. Title 24, California Code of Regulations. PLANNING COMMISSION RESOLUTION NO. 2827 16 I. California Fire Code and its appendices and standards. 71. This project will fall under the review and compliance of Chapters 11-A and Chapter 11- B of the 2019 California Building Code. 72. The Applicant shall coordinate directly with: Riverside County Fire Marshal’s Office CAL FIRE/Riverside County Fire Department Main: (760) 863-8886 77933 Las Montañas Road, Suite 201 Palm Desert, CA 92211 73. Plan approval must be obtained from the County of Riverside Department of Environmental Health (Health Department) before constructing or altering structures or equipment (such as fencing and decking). The Applicant shall coordinate directly with the Health Department for the application, plans, and specifications. 74. All trash enclosures are required to be accessible. Provide an accessible path of travel to the trash enclosure. Trash enclosures shall comply with the minimum requirements established by Section 8.12 of the PDMC. 75. All contractors and subcontractors shall have a current City of Palm Desert Business License before permit issuance per PDMC, Title 5. 76. All contractors and/or owner-builders must submit a valid Certificate of Workers’ Compensation Insurance coverage before the issuance of a building permit per California Labor Code, Section 3700. 77. Address numerals shall comply with Palm Desert Ordinance No. 1351 (PDMC Section 15.28). Compliance with Ordinance 1351 regarding street address location, dimension, a stroke of line, distance from the street, height from grade, height from the street, etc., shall be shown on all architectural building elevations in detail. Any possible obstructions, shadows, lighting, landscaping, backgrounds, or other reasons that may render the building address unreadable shall be addressed during the plan review process. The Applicant may request a copy of Ordinance 1351 or PDMC Section 15.28 from the Building and Safety Division counter staff. FIRE DEPARTMENT: 78. Construction Permits: Building construction plans shall be submitted to the Office of the Fire Marshal for review and approval. Additional fire and life safety conditions may be determined during this review. 79. The proposed project may have a cumulative adverse impact on the Fire Department's ability to provide an acceptable level of service. These impacts include an increased number of emergency and public service calls due to the increased presence of PLANNING COMMISSION RESOLUTION NO. 2827 17 structures, traffic, and population. The Project proponents/developers will be expected to provide for a proportional mitigation of these impacts via capital improvements and/or impact fees. 80. Fire Department emergency vehicle apparatus access road locations and design shall be in accordance with the California Fire Code and Riverside County Fire Department Standards. Plans must be submitted to the Fire Marshal’s office for review and approval prior to building permit issuance. 81. Fire Department water system(s) for fire protection shall be in accordance with the California Fire Code and Riverside County Fire Department Standards. Plans must be submitted to the Fire Department for review and approval prior to building permit issuance. 82. Construction shall remain accessible and exposed for inspection purposes until approved by the Fire Department. The approval of plans and specifications does not permit the violation, deletion, omission, or faulty installation of any requirements of the California Code of Regulations, Title 19, Title 24, and locally adopted ordinances. END OF CONDITIONS OF APPROVAL G:\Planning\Case Files\PP\PP 22-0007 - Carmax Expansion - Amendment to CUP 17-059\PC\PP-CUP 17-059 Amendment #1 - Public Hearing Notice (1.17.22).docx CITY OF PALM DESERT PUBLIC HEARING NOTICE CASE NO. PP/CUP 17-059 AMENDMENT NO. 1 / EA22-0007 NOTICE IS HEREBY GIVEN THAT A PUBLIC HEARING WILL BE HELD BEFORE THE PLANNING COMMISSION OF THE CITY OF PALM DESERT, CALIFORNIA, TO REVIEW A REQUEST BY MICHAEL BAKER INTERNATION FOR THE ADOPTION OF NOTICE OF EXEMPTION PURSUANT TO THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) AND APPROVAL OF A PRECISE PLAN AND CONDITIONAL USE PERMIT AMENDMENT FOR THE EXPANSION OF AN EXISTING CARMAX AUTO SALES FACILITY LOCATED AT 73450 AND 73500 DINAH SHORE DRIVE The City of Palm Desert (City), in its capacity as the Lead Agency for this project under the CEQA, finds that the proposed project is categorically exempt under Article 19 Section 15332 Infill Projects (Class 32) of the CEQA; therefore, no further environmental review is necessary, and that a Notice of Exemption can be adopted as part of this project. PROJECT LOCATION/DESCRIPTION: PROJECT LOCATION: 73450 and 73500 Dinah Shore Drive (APNs 694-060-034 and-036) PROJECT DESCRIPTION: The project proposes to amend existing approvals for the CarMax located at 73450 to add 2,351 square feet of sales to the existing sales building, construct a private automated carwash, expand the customer parking lot, and construct a new 176-space vehicle staging area on the site. PUBLIC HEARING: NOTICE IS HEREBY GIVEN that the Planning Commission of the City of Palm Desert, California, will hold a Public Hearing at its meeting on January 17, 2023. The Planning Commission meeting begins at 6:00 p.m. in the Council Chamber located at 73510 Fred Waring Drive, Palm Desert, California. Pursuant to Assembly Bill 361, this meeting may be conducted by teleconference. Options for remote participation will be listed on the Posted Agenda for the meeting at: https://www.cityofpalmdesert.org/our-city/committees-and- commissions/planning-commission-information-center. There will be in-person access to the meeting location. COMMENT PERIOD: The public comment period for this project is from January 6, 2023, to January 17, 2023. Public Review: The plans and related documents are available for public review Monday through Friday from 8:00 a.m. to 5:00 p.m. by contacting the project planner, Nick Melloni. Please submit written comments to the Planning Division. If any group challenges the action in court, issues raised may be limited to only those issues raised at the public hearing described in this notice or in written correspondence at or prior to the Planning Commission hearing. All comments and any questions should be directed to: Nick Melloni, Senior Planner City of Palm Desert 73-510 Fred Waring Drive Palm Desert, CA 92260 (760) 346-0611, Extension 479 nmelloni@cityofpalmdesert.org PUBLISH: DESERT SUN RICHARD D. CANNONE, AICP, SECRETARY JANUARY 6, 2023 PALM DESERT PLANNING COMMISSION ARCHITECTURAL REVIEW COMMISSION NOTICE OF ACTION December 8, 2022 Michael Baker International 75410 Gerald Ford Drive, Suite 100 Palm Desert, CA 92211 Subject: Consideration to approve a Design Review for Amendment No. 1 to Precise Plan (PP) / Conditional Use Permit (CUP) 17-059 to expand an existing CarMax, auto sales use, including a 2,351 square-foot building addition, construction of a new 923-square-foot carwash tunnel, canopy area, and new sales staging area located at 73-450 and 73-500 Dinah Shore Drive. The Architectural Review Commission of the City of Palm Desert considered your request and took the following action at its meeting of November 22, 2022: Following discussion, MOTION BY CHAIR VUKSIC, SECOND BY COMMISSIONER MCAULIFFE, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT) to: 1. Continue Case Nos. PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22-0008. 2. The applicant shall construct the wall enclosing the vehicle staging area with a tan split face block and pilasters facing Dinah Shore Drive, and the northern property line, spaced no greater than 30 feet apart. 3. All roof drainage on the proposed additions shall utilize internal roof drains. 4. Parapet ends on new tower element shall return twelve (12) feet onto existing roof. 5. Windows of new addition should be recessed to match existing south façade. 6. Header detail on new tower element should be recessed a minimum of eight (8) inches. 7. East end of new building addition and existing building should be revisited for more dimension and forms. 8. Revisit steel canopy design to look more integral to existing architecture. If you have any questions, please contact Senior Planner, Nick Melloni, at (760) 776-6479 or nmelloni@cityofpalmdesert.org. Sincerely, ROSIE LUA, SECRETARY ARCHITECTURAL REVIEW COMMISSION cc: File City of Palm Desert Page 1 ARCHITECTURAL REVIEW COMMISSION CITY OF PALM DESERT, CALIFORNIA MINUTES (HYBRID MEETING) Pursuant to Assembly Bill 361, this meeting may be conducted by teleconference. There will be in-person public access to the meeting location. 1. CALL TO ORDER A Regular Meeting of the Architectural Review Commission (ARC) was called to order by Chair Vuksic on Tuesday, November 22, 2022, at 12:30 p.m. in the Development Services Conference Room, City Hall, located at 73510 Fred Waring Drive, Palm Desert, California. 2. ROLL CALL Present: Commissioners Nicholas Latkovic, Michael McAuliffe, Francisco Sanchez, and Chair John Vuksic. Absent: Commissioner Dean Wallace Colvard and Vice Chair McIntosh. City Staff Present: Richard Cannone, Director of Development Services; Rosie Lua, Deputy Director of Development Services; Nick Melloni, Senior Planner, and Melinda Gonzalez, Recording Secretary, were present at Roll Call. 3. NON-AGENDA PUBLIC COMMENT Chair Vuksic opened and closed the non-agenda public comment period. No public comments were provided. 4. CONSENT CALENDAR Associated staff reports, memos, attachments, and discussion on the following items can be viewed by visiting the Architectural Review Commission Information Center website at, https://www.cityofpalmdesert.org/our-city/committees-and-commissions/commission- information. MOTION BY COMMISSIONER LATKOVIC, SECOND BY COMMISSIONER MCAULIFFE, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT), to approve the consent calendar. Tuesday November 22, 2022 12:30 p.m. Regular Meeting Architectural Review Commission Minutes November 22, 2022 City of Palm Desert Page 2 A. APPROVAL OF MINUTES MOTION BY COMMISSIONER LATKOVIC, SECOND BY COMMISSIONER MCAULIFFE, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT), to approve the Architectural Review Commission Regular Meeting minutes of November 8, 2022. MOTION BY COMMISSIONER LATKOVIC, SECOND BY COMMISSIONER MCAULIFFE, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT), to approve the Architectural Review Commission Special Meeting minutes of November 15, 2022. CONSENT ITEMS HELD OVER: Items removed from the Consent Calendar for separate discussion will be considered at this time. None 5. ACTION CALENDAR Associated staff reports, memos, attachments, and discussion on the following items can be viewed by visiting the Architectural Review Commission Information Center website at, https://www.cityofpalmdesert.org/our-city/committees-and-commissions/commission- information. A. FINAL DRAWINGS 1. CASE NOS: MISC22-0029 / SARC 22-0006 NATURE OF PROJECT/APPROVAL SOUGHT: Consideration to approve a Design Review and Sign Program for façade modifications to an existing Louis Vuitton store located at 73515 El Paseo, Suite 1708 APPLICANT AND ADDRESS: Gruen Associates, Los Angeles, CA LOCATION: 73515 El Paseo Suite 1708 ZONE: Downtown Core Overlay - D.O. Senior Planner, Nick Melloni, narrated a PowerPoint presentation on the item and responded to Commission inquiries. Jamie Pancino with Gruen Associates, Applicant Representative, presented additional details on the project and answered questions from the Commission. Chair Vuksic opened and closed the public comment period. No public comments were provided. Discussion on the item ensued with Commissioners providing comments for the project. Following discussion, MOTION BY COMMISSIONER MCAULIFFE, SECOND BY COMMISSIONER LATKOVIC, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT) to: 1. Approve Case Nos. MISC22-0029 / SARC 22-0006 as presented. Architectural Review Commission Minutes November 22, 2022 City of Palm Desert Page 3 2.Applicant shall provide detailed drawings to staff’s satisfaction, for review of inside corner where breeze blocks meet one another and how end treatment is supported. Should there be any issues staff cannot resolve with the Applicant the project will return to the ARC for review. 2.CASE NOS: PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22-0008 NATURE OF PROJECT/APPROVAL SOUGHT: Consideration to approve a Design Review for Amendment No. 1 to Precise Plan (PP) / Conditional Use Permit (CUP) 17- 059 to expand an existing CarMax, auto sales use, including a 2,351 square-foot building addition, construction of a new 923-square-foot carwash tunnel, canopy area, and new sales staging area located at 73-450 and 73-500 Dinah Shore Drive. APPLICANT AND ADDRESS: Michael Baker International, Palm Desert, CA LOCATION: 73-450 and 73500 Dinah Shore Drive ZONE: Service Industrial - SI Senior Planner, Nick Melloni, narrated a PowerPoint presentation on the item and responded to Commission inquiries. Bill Pope with MBI, Applicant, and Allan Price, Architect, with Pieper O’Brien Herr Architects, presented additional details on the project and answered questions from the Commission. Chair Vuksic opened and closed the public comment period. No public comments were provided. Discussion on the item ensued with Commissioners providing comments for the project. Following discussion, MOTION BY CHAIR VUKSIC, SECOND BY COMMISSIONER MCAULIFFE, CARRIED 4-0; (COMMISSIONER COLVARD and VICE CHAIR MCINTOSH ABSENT) to: 1. Continue Case Nos. PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22- 0008. 2. The applicant shall construct the wall enclosing the vehicle staging area with a tan split face block and pilasters facing Dinah Shore Drive, and the northern property line, spaced no greater than 30 feet apart. 3.All roof drainage on the proposed additions shall utilize internal roof drains. 4.Parapet ends on new tower element shall return twelve (12) feet onto existing roof. 5. Windows of new addition should be recessed to match existing south façade. 6.Header detail on new tower element should be recessed a minimum of eight (8) inches. 7.East end of new building addition and existing building should be revisited for more dimension and forms. 8.Revisit steel canopy design to look more integral to existing architecture. 6.INFORMATIONAL REPORTS & COMMENTS A.ARCHITECTURAL REVIEW COMMISSIONERS None Architectural Review Commission Minutes November 22, 2022 City of Palm Desert Page 4 B. CITY STAFF Senior Planner Melloni provided an update for the Vitalia subcommittee which met Tuesday, November 15, 2022. The Vitalia plans were found to be in substantial conformance, with a minor change for the roof screening on some of the units. The Vitalia Apartment development plans have been deemed complete therefore, the Vitalia subcommittee has been dissolved. Senior Planner Melloni provided an update on Avenida Palm Desert informing they are scheduled to begin work on the roof screening November 28, 2022. C. ATTENDANCE REPORT The attendance report was provided with the agenda materials. The Commission took no action on this matter. 7. ADJOURNMENT The Architectural Review Commission adjourned at 1:42 p.m. Respectfully submitted, Melinda Gonzalez Melinda Gonzalez, Senior Administrative Assistant Recording Secretary ATTEST: Rosie Lua Rosie Lua, Deputy Director of Development Services Secretary APPROVED BY ARC: 12/13/2022 ARCHITECTURAL REVIEW COMMISSION NOTICE OF ACTION December 14, 2022 Michael Baker International 75410 Gerald Ford Drive, Suite 100 Palm Desert, CA 92211 Subject: Consideration to approve a Design Review for Amendment No. 1 to Precise Plan (PP) / Conditional Use Permit (CUP) 17-059 to expand an existing CarMax, auto sales use, including a 2,351 square-foot building addition, construction of a new 923 - square-foot carwash tunnel, canopy area, and new sales staging area located at 73- 450 and 73-500 Dinah Shore Drive. The Architectural Review Commission of the City of Palm Desert considered your request and took the following action at its meeting of December 13, 2022: Following discussion, MOTION BY COMMISSIONER MCAULIFFE, SECOND BY COMMISSIONER COLVARD, CARRIED 5-0; (CHAIR VUKSIC ABSENT) to: 1. Approve Case Nos. PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22- 0008 with conditions. 2. The applicant shall construct the wall enclosing the vehicle staging area with a tan split face block and pilasters facing Dinah Shore Drive, and the northern property line, spaced no greater than 30 feet apart. 3. All roof drainage on the proposed additions shall utilize internal roof drains except on the north elevations of the main sales and service buil ding. 4. The areas indicated by dark earthtone stucco located on the tower elements of the south and east elevations of the sales addition shall be recessed a minimum of 0’-8” from the fascia of the tower element. Final construction drawings shall provide sufficient details for this change. If you have any questions, please contact Senior Planner, Nick Melloni, at (760) 776-6479 or nmelloni@cityofpalmdesert.org. Sincerely, ROSIE LUA, SECRETARY ARCHITECTURAL REVIEW COMMISSION cc: File City of Palm Desert Page 1 ARCHITECTURAL REVIEW COMMISSION CITY OF PALM DESERT, CALIFORNIA MINUTES (HYBRID MEETING) Pursuant to Assembly Bill 361, this meeting may be conducted by teleconference. There will be in-person public access to the meeting location. 1. CALL TO ORDER A Regular Meeting of the Architectural Review Commission (ARC) was called to order by Vice Chair McIntosh on Tuesday, December 13, 2022, at 12:31 p.m. in the Development Services Conference Room, City Hall, located at 73510 Fred Waring Drive, Palm Desert, California. 2. ROLL CALL Present: Commissioners Dean Wallace Colvard, Nicholas Latkovic, Michael McAuliffe, Vice Chair McIntosh, and Francisco Sanchez. Absent: Chair John Vuksic. City Staff Present: Richard Cannone, Director of Development Services; Nick Melloni, Senior Planner, and Melinda Gonzalez, Recording Secretary, were present at Roll Call. 3. NON-AGENDA PUBLIC COMMENT Vice Chair McIntosh opened and closed the non-agenda public comment period. No public comments were provided. 4. CONSENT CALENDAR Associated staff reports, memos, attachments, and discussion on the following items can be viewed by visiting the Architectural Review Commission Information Center website at, https://www.cityofpalmdesert.org/our-city/committees-and-commissions/commission- information. MOTION BY COMMISSIONER MCAULIFFE, SECOND BY COMMISSIONER LATKOVIC, CARRIED 5-0; (CHAIR VUKSIC ABSENT), to approve the consent calendar. A. APPROVAL OF MINUTES MOTION BY COMMISSIONER MCAULIFFE, SECOND BY COMMISSIONER LATKOVIC, CARRIED 5-0; (CHAIR VUKSIC ABSENT), to approve the Architectural Review Commission Regular Meeting minutes of November 22, 2022. Tuesday December 13, 2022 12:30 p.m. Regular Meeting Architectural Review Commission Agenda December 13, 2022 City of Palm Desert Page 2 CONSENT ITEMS HELD OVER: Items removed from the Consent Calendar for separate discussion will be considered at this time. None 5.ACTION CALENDAR Associated staff reports, memos, attachments, and discussion on the following items can be viewed by visiting the Architectural Review Commission Information Center website at, https://www.cityofpalmdesert.org/our-city/committees-and-commissions/commission- information. A.FINAL DRAWINGS 1.CASE NOS: PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22-0008 (Continued from November 22, 2022) NATURE OF PROJECT/APPROVAL SOUGHT: Consideration to approve a Design Review for Amendment No. 1 to Precise Plan (PP) / Conditional Use Permit (CUP) 17- 059 to expand an existing CarMax, auto sales use, including a 2,351 square-foot building addition, construction of a new 923-square-foot carwash tunnel, canopy area, and new sales staging area located at 73-450 and 73-500 Dinah Shore Drive. APPLICANT AND ADDRESS: Michael Baker International, Palm Desert, CA LOCATION: 73-450 and 73500 Dinah Shore Drive ZONE: Service Industrial - SI Senior Planner, Nick Melloni, narrated a PowerPoint presentation on the item and responded to Commission inquiries. Bill Pope with MBI, Applicant, and Allan Price, Architect, with Pieper O’Brien Herr Architects, provided additional information on the project and answered questions from the Commission. Vice Chair McIntosh opened and closed the public comment period. No public comments were provided. Discussion on the item ensued with Commissioners providing comments for the project. Following discussion, MOTION BY COMMISSIONER MCAULIFFE, SECOND BY COMMISSIONER COLVARD, CARRIED 5-0; (CHAIR VUKSIC ABSENT) to: 1.Approve Case Nos. PP/CUP 17-059 – Amendment #1 / EA 22-0007 / PMW 22- 0008 with conditions. 2.The applicant shall construct the wall enclosing the vehicle staging area with a tan split face block and pilasters facing Dinah Shore Drive, and the northern property line, spaced no greater than 30 feet apart. 3.All roof drainage on the proposed additions shall utilize internal roof drains except on the north elevations of the main sales and service building. 4.The areas indicated by dark earthtone stucco located on the tower elements of the south and east elevations of the sales addition shall be recessed a minimum of 0’- 8” from the fascia of the tower element. Final construction drawings shall provide sufficient details for this change. Architectural Review Commission Agenda December 13, 2022 City of Palm Desert Page 3 B. MISCELLANEOUS None 6. INFORMATIONAL REPORTS & COMMENTS A. ARCHITECTURAL REVIEW COMMISSIONERS None B. CITY STAFF Senior Planner, Nick Melloni, provided the following updates: • PP/EA22-0005 West Coast Storage and PP/CUP22-0006 394-units on the SWC of Portola Ave. and Frank Sinatra Drive went before the Planning Commission on December 6, 2022, both projects were approved. • A workshop was held last week for the proposed North Sphere Regional Park. Director of Development Services, Richard Cannone, added a follow up workshop is scheduled for January 15, 2023. Information on the follow up workshop will be sent to commissioners when available. • Avenida Palm Desert is currently installing their roof screening. • The next regularly scheduled Architectural Review Commission meeting on December 27, 2022, will be canceled due to lack of a quorum. Cancellation notices will be posted as required and emailed to Commissioners. • An update to the City’s Accessory Dwelling Unit (ADU) ordinance will go before the City Council for adoption at their next meeting, December 15, 2022. C. ATTENDANCE REPORT The attendance report was provided with the agenda materials. The Commission took no action on this matter. 7. ADJOURNMENT The Architectural Review Commission adjourned at 1:21 p.m. Respectfully submitted, Melinda Gonzalez Melinda Gonzalez, Senior Administrative Assistant Recording Secretary ATTEST: Rosie Lua Rosie Lua, Deputy Director of Development Services Secretary APPROVED BY ARC: 1/10/2023 Notice of Exemption FORM “B” NOTICE OF EXEMPTION TO: Office of Planning and Research P. O. Box 3044, Room 113 Sacramento, CA 95812-3044 FROM: City of Palm Desert 73-510 Fred Waring Drive Palm Desert, CA 92260 Clerk of the Board of Supervisors or County Clerk County of: Riverside 2724 Gateway Dr, Riverside, CA 92507 1. Project Title: PP/CUP Amendment No. 1 / EA 22-0007 2. Project Applicant: Michael Baker International 3. Project Location – Identify street address and cross streets or attach a map showing project site (preferably a USGS 15’ or 7 1/2’ topographical map identified by quadrangle name): Dinah Shore Drive at 73450 (Parcel “A” – APN 694- 060-036) and (Parcel “B” – APN 694-060-034) 4. (a) Project Location – City: Palm Desert (b) Project Location – County: Riverside 5. Description of nature, purpose, and beneficiaries of Project: The Applicant, Michael Baker International, requests approval of a Precise Plan (PP) and Conditional Use Permit Amendment, and an Environmental Assessment (EA) to expand a CarMax outdoor automobile sales facility. The expansion will include a 2.17-acre portion of the project site consisting of the following modifications: • A 2,351-square-foot sales office expansion to an existing 6,841-square-foot sales/auto service building. • A new 923-square-foot private carwash building for service of onsite vehicles. • A new 560-square-foot shade canopy addition. • Expansion to the existing parking lot, adding 55 new on-site parking spaces for customers and employees. This expansion will require the removal of 14 existing spaces resulting in a net increase of 40 spaces to the site for a total of 100 parking spaces. • Construction of a new 176-space sales staging area on a 1.9-acre vacant parcel located west of CarMax will be enclosed by a six-foot-high (6’) block wall and feature new parking lot lighting. 6. Name of Public Agency approving project: City of Palm Desert 7. Name of Person or Agency undertaking the project, including any person undertaking an activity that receives financial assistance from the Public Agency as part of the activity or the person receiving a lease, permit, license, certificate, or other entitlement of use from the Public Agency as part of the activity: Michael Baker International Notice of Exemption FORM “B” 8. Exempt status: (check one) (a) Ministerial project. (Pub. Res. Code § 21080(b)(1); State CEQA Guidelines § 15268) (b) Not a project. (c) Emergency Project. (Pub. Res. Code § 21080(b)(4); State CEQA Guidelines § 15269(b),(c)) (d) Categorical Exemption. State type and section number: State CEQA Guidelines §15332 – “Class 32 – Infill Project” (e) Declared Emergency. (Pub. Res. Code § 21080(b)(3); State CEQA Guidelines § 15269(a)) (f) Statutory Exemption. State Code section number: (g) Other. Explanation: General Rule – Section 15061(b)(3) 9. Reason why project was exempt: The project is exempt from CEQA per Section 15332 of the CEQA guidelines as the project is a Class 32 Exemption for “in-fill” development. Class 32 is intended for projects characterized as in-fill developments satisfies the conditions described below: 1) The project is consistent with the applicable General Plan designation and all applicable General Plan policies. As analyzed, the project includes an additional 2,351-square- foot addition to a retail sales building, a 923- square-foot carwash building, and an expansion of parking areas. The proposed project complies with the development standards within the SI zoning designation. 2) The project occurs on a 2.17-acre portion of the project site, which is less than five (5) acres specified in the criteria of the Class 32 exemption and is substantially surrounded by urban uses. 3) The site has no value as a habitat for endangered, rare, or threatened species. The site has been previously graded and is occupied by existing portable building structures and a greenhouse. The site is not identified as a suitable habitat for endangered species in the Coachella Valley Multi-Species Habitat Conservation Plan (MSHCP). 4) Additionally, approval of the project would not result in any significant effects relating to traffic, noise, air quality, or water quality. The proposed use will not result in significant noise that will violate the City’s Noise Notice of Exemption FORM “B” Ordinance. In addition, the City Engineer has reviewed the proposed use and the existing infrastructure, including the off-site improvements, and staff finds the use will not have a significant effect on traffic. The applicant has provided a Traffic Impact Assessment Letter identifying that the project expansion will generate up to two (2) trips produced at a.m. peak hours and 16 trips produced at p.m. peak hours, increasing the project total to 96 per day. No intersections within the area of the project site will be impacted by the additional trips. This project will not adversely impact the surrounding traffic system per the County of Riverside Analysis Guidelines for Level of Service and Vehicle Miles Traveled adopted in December 2020 (TIA Guidelines), which are adopted by reference by the City of Palm Desert for the purpose of traffic review. The TIA guidelines indicate that projects that generate less than 100 peak-hour trips typically do not affect the level of service (LOS). Additionally, the TIA guidelines indicate that the mini-storage yards (personal storage) are an activity that will not require a TIA. In addition, a preliminary grading plan and hydrology report have been submitted for review, and final approval will commence as part of the conditions of approval herein. No other significant noise or air quality effects were identified for the project. 5) Finally, the site can be adequately served by all required utilities and public services. The proposed project has been reviewed by various utility agencies and public services, including Southern California Edison, the Coachella Valley Water District, and Burrtec Waste Management. These agencies have not identified that utilities in the area are insufficient to serve the proposed office building and parking area. Additionally, the project is not subject to any of the exceptions for categorical exemptions identified in CEQA Guidelines Section 15300.2: 1) The project qualifies as a Class 32 exemption, which is not listed as one of the classes under 15300.2 (A). The project is not located on a site where it may have an adverse impact on an environmental resource of hazardous or critical concern where designated, precisely mapped, and officially adopted pursuant to law by federal, state, or local agencies. The project site will not impact designated environmental or biological resources as it is not located within Notice of Exemption FORM “B” a conservation area as identified by the Coachella Valley Multiple Species Habitat Conservation Plan. 2) The project will not have a cumulative impact on the environment. The proposal does not conflict with additional impacts in terms of traffic generation. The proposal will expand existing parking areas and construct new admin and storage buildings that replace existing portable buildings used for the same functions. As indicated by the traffic impact assessment prepared for the project, no significant traffic impacts are anticipated. 3) There are no unusual circumstances on the project site. The project site is not located within a flood zone per the latest FEMA Flood Zone Maps. The project site is located within an Urban area per Fire Hazard Severity Zone maps available from the Riverside County Fire Department and depicted in Figure 8.5 on Page 119 of the General Plan. The project site is not identified within an Alquist-Priolo Fault Zone per the latest maps on file with the California Department of Conservation; the nearest fault zone is the San Andreas Fault located north of the Palm Desert City Limits. 4) The project site is not located in proximity to any scenic highway. The nearest officially designated scenic highway is Highway 74, located outside of the Palm Desert City Limits approximately 5.6 miles to the south of the project site. 5) The project site is identified as a historic waste site on any list compiled per Section 65962.5 of the Government Code. 6) The project site does not contain any existing designated historic resource and is not within a designated historic preservation district. The site is vacant. 10. Lead Agency Contact Person: Nick Melloni, Senior Planner Telephone: (760) 346-0611 11. If filed by applicant: Attach Preliminary Exemption Assessment (Form “A”) before filing. 12. Has a Notice of Exemption been filed by the public agency approving the project?  Yes  No 13. Was a public hearing held by the lead agency to consider the exemption?  Yes  No If yes, the date of the public hearing was: January 17, 2023 Notice of Exemption FORM “B” Signature: Date: January 17, 2023 Title: Senior Planner  Signed by Lead Agency  Signed by Applicant Date Received for Filing: (Clerk Stamp Here) Authority cited: Sections 21083 and 21100, Public Resources Code. Reference: Sections 21108, 21152, and 21152.1, Public Resources Code. k July 22, 2022 Centerpoint Integrated Solutions 1626 Cole Boulevard, Suite 125 Lakewood, CO 80401 Attn: Scott Dallam Subject: City of Palm Desert CarMax Expansion - Traffic Scoping Letter Michael Baker International (Michael Baker) has reviewed the proposed CarMax expansion (Project) located on Dinah Shore Drive in the City of Palm Desert relative to the required traffic operations analysis. The purpose of this memorandum is to document the site trip generation analysis and findings, and to provide recommended next steps. Trip generation rates were evaluated using both the Institute of Transportation Engineer’s Trip Generation Manual and rates calculated using existing count data. Based on the County of Riverside Transportation Analysis Guidelines for Level of Service, Vehicle Miles Traveled (December 2020), intersections where the Project will add 50 or more peak hour trips require evaluation. The CarMax expansion is anticipated to add approximately 2 new trips during the AM Peak Hour and 16 new trips during the PM Peak Hour. Therefore, there are no intersections in the immediate area of the site where 50 or more trips will be added due to the Project and no further study is recommended. The following trip generation analysis for the proposed Project includes the details of the analysis approach and assumptions. Please review this scoping agreement and let us know if you would like any adjustments to be made in the proposed analysis approach or the assumptions. Sincerely, Carla Dietrich, P.E. (PA), PTOE Transportation Planner 1 1. Project Information Project Location: 73450 Dinah Shore Drive, Palm Desert, CA Project Description: Proposed Used Auto Sales (CarMax) Expansion Project Opening Year: 2023 (expansion) Location: 73450 Dinah Shore Drive near the Dinah Shore Drive intersection with Gateway Drive (See Exhibit 1 in Attachment A) Engineer Applicant Company: Michael Baker International Centerpoint Integrated Solutions Name: Carla Dietrich Scott Dallam (Applicant’s Representative) Address: 3536 Concours 1626 Cole Boulevard, Suite 125 City, State, Zip Code: Ontario, CA 91764 Lakewood, CO 80401 Phone #: (909) 974-4908 -- Email: cdietrich@mbakerintl.com sdallam@centerpoint-is.com A CarMax facility currently operates at 73450 Dinah Shore Drive in the City of Palm Desert. The Project proposes to expand t he existing facility including the addition of a 923 square-foot car wash, 2,337 square feet of retail building space, 55 additional customer and employee parking spaces, and 167 additional sales car parking spaces. Exhibit 1 is the project location map and Exhibit 2 details the existing and proposed site boundary along with additional description of the proposed modifications to the site. Exhibit 3 is the proposed site plan. All exhibits are contained in Attachment A – Exhibits. Table 1 summarizes key site characteristics for the existing and proposed conditions. Table 1: Site Characteristics Site Characteristic Existing Condition Proposed Change Proposed Condition Site Acreage 4.23 acres +1.90 acres 6.13 acres Building Square Footage 6,841 SF Sales Building + 936 SF Car Wash + 2,325 SF Building Expansion = 3,261 SF Total 10,102 SF Number of Employees 54 +11 65 Customer and Employee Parking Spaces East of Main Site Driveway 0 0 0 West of Main Site Driveway 46 +55 101 Total 46 +55 101 Sales Parking Spaces (Vehicle Inventory) East of Main Site Driveway 154 -9 145 West of Main Site Driveway 0 +176 176 Total 154 +167 321 Note: SF = Square Feet The CarMax property is currently accessed via a signalized intersection at the Dinah Shore Drive and Gateway Drive/CarMax Driveway Intersection. This is the main access to the property. A secondary gated access exists on the east side of the property that can be used by employees only for CarMax vehicles entering/exiting during test drives. No modifications to the site access are being recommended as part of the expansion project. 2 2. Trip Generation Trip Credit The existing active land use is a currently operational CarMax. The proposed land use will include maintaining the existing operations plus and expansion of the facility. The existing CarMax facilities will not be removed from the site. Due to the nature of the site, the following trip adjustments are proposed: • Internal Trip Reduction = 0% • Pass-by Trip Reduction = 0% Finding: Since the existing CarMax site will remain and be expanded, no trip generation credits are being proposed for this Project. Trip Generation Rates Potential trip generation rates were examined using two methods: 1) ITE – Institute of Transportation Engineers (ITE) Trip Generation Manual, 11th edition trip rates. 2) Traffic Counts – Rates calculated using existing count data and site characteristics. Table 2 shows the ITE Trip Generation Manual, 11th edition trip rates for the Automobile Sales (Used) Land Use Code 841. Trip rate units for both thousand square feet and number of employees are shown in the table. Table 2: ITE Trip Generation Manual Trip Rates Land Use ITE Code Unit Average Trip Rate Daily AM Peak Hour PM Peak Hour Rate Rate In Out Rate In Out Automobile Sales (Used) 841 KSF 27.06 2.13 76% 24% 3.75 47% 53% 841 Employees 12.48 1.16 76% 24% 1.73 47% 53% Source: ITE Trip Generation Manual, 11th Edition Notes: 1) Saturday data not available in the manual. 2) KSF = Thousand Square Feet Traffic counts of the site entering and exiting traffic at the Dinah Shore Drive and Gateway Drive/CarMax Driveway Intersection were collected on Saturday, June 18, 2022, from 11 AM to 3 PM and Tuesday, June 21, 2022, from 7 AM to 9 AM and 4 PM to 6 PM. The traffic count data is included in Attachment B – Traffic Counts. The trip rates for the peak hours shown in Table 3 were derived using the actual count data for the AM Peak Hour, PM Peak Hour, and Saturday Peak Hour. The count data daily trip rates were estimated by applying a ratio between the ITE daily trip rate to the ITE peak hour rate. Two daily rates were estimated, one for each peak, and then averaged to get an estimated daily trip rate based on the count data. Table 3: Actual Count Trip Rates Land Use Unit Average Trip Rate Daily AM Peak Hour PM Peak Hour Saturday Peak Hour Rate Rate In Out Rate In Out Rate In Out Automobile Sales (Used) KSF 52.41 1.61 82% 18% 11.69 63% 38% 11.55 52% 48% Employees 6.42 0.20 82% 18% 1.48 63% 38% 1.46 52% 48% Acre -- 2.60 82% 18% 18.91 63% 38% 18.68 52% 48% Note: Daily rate for the unit acres is not shown since an ITE rate is not available to calculate a ratio. 3 A comparison traffic count data trip rates and the ITE Trip Generation Manual rates shows the following: • Unit = Thousand Square Feet – The AM rate using the count data is 24% lower (1.61 vs. 2.13) than the ITE Trip Generation Manual rate while the PM rate is over 200% higher (11.69 vs. 3.75). • Unit = Employees – Both the AM and PM rates using the existing count data are lower than the ITE Trip Generation Manual. The critical PM Peak Hour traffic count is less than 15% lower than the ITE trip rate. The Saturday traffic count was collected to determine if car shopping is greater on Saturdays compared to a typical weekday. A comparison of the trips rates from the existing count data shows that the Saturday rates were slightly lower than the Weekday PM Peak Hour. Therefore, it can be concluded that the Weekday PM Peak Hour represents the worst case and there is no need to further evaluate the Saturday condition. Trip Generation Analysis The trip generation rates calculated in Table 2 and Table 3 were utilized to calculate the estimated site trips associated with the CarMax expansion as shown in Table 4. The expansion will include an additional 3,261 square-footage of building space, 11 employees, and 1.90 acres. The square footage expansion includes 2,325 square-feet of sales area expansion and 936 square-feet of car wash building. While the square footage associated with the car wash is not likely to result in additional trips, it was included in the “new” square footage to represent a conservative approach. Table 4: Expansion Estimated Site Trips (Multiple Methods/Rates) Land Use Unit Project Expansion Value Estimated Number of Trips Daily AM Peak Hour PM Peak Hour Total In Out Total In Out ITE Trip Gen Manual Rates KSF 3.261 88 7 5 2 12 6 6 Employees 11 137 13 10 3 19 9 10 Traffic Count Rates KSF 3.261 171 5 4 1 38 24 14 Employees 11 71 2 2 0 16 10 6 Acre 1.90 -- 5 4 1 36 23 13 Note: The expansion value is the change due to the expansion, or the “new” building square footage, employees, and acres). The ITE Trip Generation Manual is an appropriate source, particularly when local or site-specific information is not available. An evaluation of the standard deviation associated with ITE rates indicated a preference for obtaining local data. Given these factor s, it is recommended that the trip generation rates developed using the traffic count data be utilized. With the unique nature of the facility where the inventory is stored outside of the building, the building square footage may not be the ideal independent variable. The number of employees, however, provide a more direct correlation with employee vehicle trips and the number of customers anticipated to visit the site. Therefore, the count data trips rates by employee are recommended for this analysis. Table 5 summarizes the recommended trip generation rates, the estimated new site trips due to the expansion, as well as summarizes the total site trips including existing trips based on the count data. 4 Table 5: Recommended Trip Rates & Estimated Site Trips Land Use Estimated Number of Trips Daily AM Peak Hour PM Peak Hour Total In Out Total In Out Expansion of Existing CarMax Rate and Percent In/Out 6.42 0.20 82% 18% 1.48 63% 38% New Site Trips 71 2 2 0 16 10 6 Total Site Trip Components Existing Site N/A 11 9 2 80 50 30 Expansion (New Site Trips) 71 2 2 0 16 10 6 Total N/A 13 11 2 96 60 36 Note: N/A = Not available. The County of Riverside Transportation Analysis Guidelines for Level of Service, Vehicle Miles Traveled (December 2020) was referenced for guidance on how to establish level of service analysis study intersections. According to those guidelines, the minimum area to be studied shall include any intersection of 2 or more Collector or higher classification streets, at which the project will add 50 or more peak hour trips, not exceeding a 5-mile radius from the project site. Based on the estimated trips shown in Table 5, the Project is anticipated to add approximately 2 new trips during the AM Peak Hour and 16 new trips during the PM Peak Hour. Assuming all trips would enter and exit at the main CarMax driveway along Dinah Shore Drive, the concentration of trips at that single intersection is not greater than the 50-trip threshold. Therefore, there are no intersections in the immediate area of the site where 50 or more trips will be added due to the proposed CarMax expansion. As a result, no further study is recommended. It can be noted that if an alternative trip rate were to be utilized, either using the ITE rates or the count data rates, the 50-trip threshold would still not be met under any of the options. Attachment A – Exhibits Exhibit 1 City of Palm Desert CarMax Expansion Project Area 10 10 DINAH SHORE DR GERALD FORD DR RAMON RD COUNTRY CLUB DR PROJECT SITE Exhibit 2 Project Existing and Proposed Boundaries City of Palm Desert CarMax Expansion LEGEND: Existing Site Boundary Proposed Site Expansion Main Site Driveway 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 07/12/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132VICINITY MAPOWNER ARCHITECTAPPLICANTPROJECT DATA Attachment B – Traffic Counts City: Location: Date: Count Type: Entering Exiting Total 7:00 2 0 2 7:15 1 0 1 7:30 3 1 4 7:45 3 0 3 8:00 2 1 3 8:15 0 0 0 8:30 1 0 1 8:45 4 0 4 TOTAL 16 2 18 Entering Exiting Total 16:00 2 5 7 16:15 14 8 22 16:30 15 8 23 16:45 16 8 24 17:00 5 6 11 17:15 8 12 20 17:30 10 10 20 17:45 1 8 9 TOTAL 71 65 136 AM Peak Hour 9 2 11 82%18%-- PM Peak Hour 50 30 80 63%37%-- Tuesday, 6/21/2022 Palm Desert Car Max Driveway at Dinah Shore Drive Driveway Count Counts Unlimited, Inc. PO Box 1178 Corona, CA 92878 (951) 268-6268 City: Location: Date: Count Type: Entering Exiting Total 11:00 9 6 15 11:15 4 5 9 11:30 11 11 22 11:45 7 4 11 12:00 3 4 7 12:15 10 7 17 12:30 8 4 12 12:45 11 10 21 13:00 12 11 23 13:15 10 6 16 13:30 8 6 14 13:45 9 12 21 14:00 13 12 25 14:15 7 6 13 14:30 12 8 20 14:45 6 12 18 TOTAL 140 124 264 SAT Peak Hour 41 38 79 52%48%-- Palm Desert Car Max Driveway at Dinah Shore Drive Saturday, 6/18/2022 Driveway Count Counts Unlimited, Inc. PO Box 1178 Corona, CA 92878 (951) 268-6268 Revision History Date Comment CARMAX AUTO SUPERSTORE NO. 6113 BUILDING/PARKING LOT EXPANSION AND CARWASH ADDITION PRELIMINARY HYDROLOGY AND HYDRAULICS STUDY CITY OF PALM DESERT Date: August 2022 Prepared for: CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 Telephone: (804) 747-0422 x 4237 Report Prepared By: Michael Baker International 75-410 Gerald Ford Drive, Suite 100 Engineer of Work/ Contact Person: Palm Desert, CA. 92211 Todd Pitner, P.E. Telephone: (760) 346-7481 Danielle Peltier, EIT MBI JN: 190260 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 SECTION 1 – INTRODUCTION 1.1 BACKGROUND Michael Baker International has been retained by CarMax Auto Superstores, Inc. to prepare a preliminary engineering design for the CarMax Auto Superstore Building/Parking Lot Expansion and Carwash Addition located at 73-450 Dinah Shore Drive in Palm Desert, CA 92211. This report shows how stormwater runoff from the 100-year storm event shall be handled on-site for proper storm water handling, preventing negative impacts to public drainage facilities and local water resources. The project site is about 300 feet northwest of the intersection at Dinah Shore Drive and Gateway Drive. Figure 1 below shows the general vicinity of the project location. The approximate 2-acre site is on a vacant, undeveloped lot northwest of the existing store parking lot. The property currently lies within a FEMA mapped flood plain Zone X, areas determined to be outside the 0.2% annual chance floodplain (Appendix A). Runoff from the proposed development will be collected in storm drain facilities and directed to an underground retention basin in which overflow will drain into an existing, offsite channel adjacent to the property that ultimately discharges to a regional retention basin that is located about 0.75 mi southeast of the project. The channel and regional basin are owned, operated, maintained, and improved by the City of Palm Desert. Reference maps are available in Appendix B. Figure 1. Vicinity Map Figure 2. Retention Basin in Relation to Project Site MID-VALLEY CHANNEL REGIONAL RETENTION BASIN PROJECT SITE www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 1.2 OBJECTIVE The objective of this report is to determine the 100-year on-site discharges in accordance with the criteria and procedures described the Riverside County Flood Control & Water Conservation District (RCFCD&WCD) Hydrology Manual. The calculations included in this report have been prepared to show the required storage volume for on-site retention determined by the 100-year, 24-hour storm event. As of June 15, 2009, developers must comply with the Colorado River Basin Regional Water Quality Control Board (CRBRWCB) requiring the preparation, approval, and implementation of a project-specific WQMP for discretionary New Developments and Redevelopment projects that fall into one (1) of the eight (8) priority development project categories. This project falls into category 8; “Parking lots of 5,000 square feet or more or with 25 or more parking spaces and potentially exposed to Urban Runoff”. A separate submittal will be made for the final project-specific WQMP. SECTION 2 – PROJECT DESCRIPTION 2.1 EXISTING CONDITIONS The proposed project site is located northwest of the existing CarMax store and consists of an undeveloped lot with poor land cover with an existing access driveway. The proposed project will also include minor improvements to the existing store. The CarMax property consists of Parcels A and B which can be seen below in Figure 3. The existing store and its associated parking lots are located on Parcel A, which utilizes an above ground infiltration basin located on the southeast corner of the property. The street-fronting landscaped area of the property is a Self-Treating Area (STA) in which runoff sheet flows into public drainage facilities in Dinah Shore Drive. Landscape adjacent to the Mid-Valley Channel is also a separate STA that drains offsite to the channel. Runoff from the remaining landscape, parking lots and building sheet flows into gutters that lead to the private infiltration basin. When the retention basin is filled to capacity, an overflow weir allows stormwater to drain into the City owned, operated, maintained, and improved storm water channel located northeast of, and adjacent to, the site. There is no stormwater run-on from neighboring land. PARCEL B PARCEL A Figure 3. Parcel Distinction www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 The runoff of the undeveloped land on Parcel B flows from the high point at the northwest end of the lot, outwards toward the perimeter of the property. The runoff has three discharge points: the existing CarMax, Dinah Shore Drive, and the Mid-Valley Channel. Reference the Existing Condition Hydrology Exhibit in Appendix C for further details. 2.2 PROPOSED CONDITIONS The proposed development will include a 2,351 square feet expansion of the existing CarMax Superstore building, the construction of a 923 square feet carwash, and extension of the parking lot on the northwest end of Parcel A onto Parcel B. Demolition of the access driveway will make way for construction of an asphalt sales area on Parcel B. Landscape areas will be added along the perimeter of Parcel B similar to the existing development layout on Parcel A. The changes occurring on Parcel A will integrate with the current flow patterns; sheet flow into gutters that lead to the private retention basin. The proposed developments on Parcel A will replace impervious asphalt with impervious building, resulting in negligible changes in runoff volumes. Underground retention chambers will be used to capture runoff from the development of Parcel B, overflow will be directed to the adjacent Mid-Valley Channel. The drainage management areas (DMAs) will include the paved areas on Parcel B and a portion of the proposed landscape. The runoff from the proposed sales area flows in the eastern direction towards the three underground chambers’ inlets. One of the inlets will capture runoff only from the southeastern corner of the proposed sales staging area. The two larger of the three are located at the low point of the parcel and receive runoff from the majority of the project site; one receives runoff from the new sales staging area and the other from the parking lot extension. Runoff from the landscape area included in the DMA will flow in the northeast direction, joined by runoff from the adjacent parking lot extension that flows in the northern direction, and into a gutter that directs runoff to the catch basin inlet. The remaining landscape areas will be STAs. A STA is an area within a project site that does not drain to a site design Best Management Practice (BMP) but drains directly offsite or to the MS4, rather than having its runoff comingle with runoff from the impervious surfaces. The STAs were excluded from the sizing of the underground basin. The landscape on the west end of the parcel will have runoff flow onto Dinah Shore Drive, joining public drainage facilities. Runoff from the remaining landscape on the northern perimeter will follow existing flow patterns: flow outwards from the property onto City owned land that discharges into the Mid-Valley Channel. Landscape on the northeastern perimeter will do the same, however, this area is closer to the storm channel and will travel a short distance to discharge into the Mid-Valley Channel. The Hydrology Exhibit of the Post-Development Conditions can be found in Appendix C. SECTION 3 – HYDROLOGY 3.1 APPROACH AND METHODOLOGY The hydrologic analysis described in this report was performed in accordance with the criteria and procedures outlined in the Riverside County Flood Control and Water Conservation District Hydrology Manual dated April 1978, referred to hereafter as “Hydrology Manual”. Hydrologic calculations to evaluate surface runoff associated with the 100-year storm event were performed using data from the Web Soil Survey and NOAA Atlas Point Precipitation Frequency Estimates to find soil classification and rainfall intensity values. The Web Soil www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 use is shown below in Table 1. Watershed losses generally consist of infiltration, depression storage, vegetation, and minor amounts of evaporation. Loss rates vary with each land use and soil type. The procedures and criteria used in this study for estimating loss rates follow the guidelines of the Hydrology Manual. The Antecedent Moisture Condition (AMC) indicates the soil wetness prior to a particular storm and the runoff potential for the subject storm. An AMC is defined as: AMC I: Lowest runoff potential AMC II: Moderate runoff potential AMC III: Highest runoff potential AMC II was applied for the 100-year storm event as outlined in the Hydrology Manual. 3.2 STORAGE VOLUMES The project site is part of a Hydrology Study done in 2002 for Monterey 170 LLC Parcel Map No. 24255 in which the City of Palm Desert proposed a retention basin for the incremental increase in runoff, due to development, for the 100-year 24-hour storm. In 2006 another Hydrology Study for Palm Desert Assessment District 2004-02 was done for 330 acres south of the site to address the same conditions as PM 24255, and the existing master retention basin located at the northeast corner of Parcel Map No. 24255 was made larger. The existing retention basin is a long rectangular basin with 1.5:1 side slopes and Geo-Web material to maintain slope stability and allow percolation during and after storms (a percolation rate of 2 inches per hour was used in the calculations). A successive report from 2005, Retention Basin for Palm Desert Assessment District 2004-02 combined with Parcel Map No. 24255 (Monterey 170), was approved detailing the total incremental increase in runoff, due to development, for the 100-year, 24-hour storm for the total tributary area bounded on the west by Monterey Avenue, on the north by the railroad tracks, on the east by Portola Avenue, and on the south by Gerald Ford Drive. Per the Palm Desert Municipal Code, developments, or redevelopments, of one acre or more in size shall be designed to retain the stormwater from a 100-year, 24-hour duration storm on-site, therefore the proposed building and parking lot expansion will retain the existing condition 100-year, 24-hour storm on-site. The local ordinance requirement will be satisfied with the combined retention of the existing condition 100-year 24-hour storm on-site and the retention of runoff from the developed conditions in the regional retention basin. A spreadsheet based on the shortcut method synthetic unit hydrograph approach as Table 1 - WQMP Land-Use Summary Area Asphalt Concrete Building Landscape % Impervious % Pervious Sq-ft Acres Sq-ft Sq-ft Sq-ft Sq-ft 71.94 28.06 94,359 2.17 61,712 2,893 3,274 26,479 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 100-year 24-hour storm on-site and the retention of runoff from the developed conditions in the regional retention basin. A spreadsheet based on the shortcut method synthetic unit hydrograph approach as prescribed by the Hydrology Manual has been utilized to perform the calculations. Basin storage capacity is modeled based on the “truncated pyramid” formula, a more conservative estimate than “averaged end areas” sometimes used. Rainfall input data for the 100-year, 24- hour storm is input per said Hydrology Manual. Basin Inflow is modeled in 15-minute intervals for the 24-hour storm, based on the design storm unit hydrographs presented in the manual. The full calculations can be found in the Synthetic Unit Hydrograph Calculations Section of this Report in Appendix E. The 100-year, 24-hour storm yields a maximum volume of approximately 6,213 cubic feet. The proposed underground retention chamber system has a capacity of approximately 6,448 cubic feet. The determined area of the top and bottom of the retention basin is approximately 1,969 square feet. The maximum depth of the retention basin design on the Unit Hydrograph calculations was edited to have the maximum storage match the installed design volume to ensure accurate calculations of the basin storage. The edit is needed to show the actual volume of the chambers that does not include the depth of the gravel bed. This reflects the volume of the basin that is free space and is available for stormwater. ADS StormTech drawings are included in Appendix F that show the preliminary layout, sections, and details of the underground system; further specifications such as invert evaluations will be provided in the Final Hydrology and Hydraulics Study. 3.3 DRAWDOWN TIME DETERMINATION Drawdown time is the amount of time the design volume takes to pass through the effective storage area of the retention basin. The drawdown time must not exceed 48 hours in order to implement proper vector control and prevent other nuisance issues. The drawdown time for the proposed underground storage basin was analyzed using an infiltration rate acquired by two percolation tests. The percolation test measures the length of time required for a quantity of water to infiltrate into the soil, this is often called a “percolation rate”. The percolation rate is related to, but not equal to, the infiltration rate. The infiltration rate is a measure of the speed at which water progresses downward into the soil and the percolation rate measures the downwards and lateral progression through the soil. Based on the “Porchet Method”, the following equation was used to convert the percolation rates to the tested infiltration rate, I t: The percolation testing determined an infiltration rate of 5.51 in/hr and 5.38 in/hr. A design www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 factor of safety prescribed by the Stormwater Quality Best Management Handbook for Low Impact Development was used to determine a design infiltration rate. The factor of safety is used to account for the actual infiltration rate of the soil which is influenced by the heterogeneous nature of soil, post-grading compaction and accumulation of sedimentary particles at the infiltration surface. A factor of safety of 3 was applied to the acquired more conservative 5.38 in/hr infiltration rate. This resulted in a design infiltration rate of 1.79 in/hr. However, the Palm Desert maximum infiltration rate for design is 1 in/hr, therefore 1 in/hr was used to calculate the drawdown time of 39.34 hours, which falls within the 48-hour maximum. The drawdown calculation and percolation test sheets can be found in Appendix E. 3.4 RATIONAL METHOD HYDROLOGY RESULTS The peak 100-year discharges were calculated using the Rational Method via CivilDesign software, as prescribed by the Hydrology Manual. The calculated design flow rate of 4.02 cubic feet per second in DMA A1, 0.84 cubic feet per second in DMA A2, and 2.63 cubic feet per second in DMA A3 were used for the sizing of the inlet catch basins within each drainage areas. A 36”x36” grate will be used in A1 and A3 and a 24”x24” grate will be used in A2, ensuring an acceptable depth and gutter spread at each inlet. Since there will be a negligible change in runoff due the expansion on Parcel A, the preliminary size of the proposed catch basin inlet added to the existing drainage system is suggested to be 24”x24”; a detailed calculation of the grate inlet will be performed in the Final Report. Detailed rational method calculations and catch basin inlet size calculations can be found in Appendix G. Storm drain size calculations will be provided in the Final Report along with an in-depth discussion of Manning’s N values. SECTION 4 – CONCLUSION The methodologies used in this study are in compliance with the City of Palm Desert and RCFC&WCD Criteria. The project site lies within FEMA designated Zone X, Areas determined to be outside the 0.2% annual chance floodplain. The underground storage chambers will retain the volume of 100% of the 100-year 24-hour storm of the existing condition. Based on these design calculations, the proposed drainage system will capture sufficient onsite runoff to prevent significant flooding during the 100-year storm event. There are no anticipated negative upstream or downstream impacts. SECTION 5 – REFERENCES 1. Riverside County Flood Control and Water Conservation District Hydrology Manual, 1978. 2. Palm Desert Water Quality Ordinance (Municipal Code Section Chapter 24.20 and 26.49) 3. Whitewater River Region Stormwater Quality Best Management Practice Design Handbook for Low Impact Development, June 2014. 4. Hydrology Study for Monterey 170 LLC Parcel Map No. 24255 in The City of Palm Desert, November 2002. 5. Hydrology Report for Retention Basin for Palm Desert Assessment District 2004- 02 combined with Parcel Map No. 24255 (Monterey 170), December 2005. 6. Hydrology Report for Palm Desert Assessment District 2004-02, June 2006. www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX A FEMA FLOOD HAZARD LAYER FIRMETTE National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 6/23/2022 at 5:42 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 116°23'17"W 33°48'19"N 116°22'39"W 33°47'50"N Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX B CITY OF PALM DESERT REGIONAL RETENTION BASIN MAPS www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX C PRE-DEVELOPMENT CONDITION HYDROLOGY MAP POST-DEVELOPMENT CONDITION HYDROLOGY MAP 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211 760-346-7481 CI V I LS T ATE OF CA L IF O RNIAREGISTERED P R O F ESSIONAL E N GI NEERTODD L . PIT NE R No. C58606 "NOT FOR CONSTRUCTION"REVISED: 08/11/2022 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERTOD D L. PITNERNo. C58606"NOT FOR CONSTRUCTION"REVISED: 08/11/2022 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX D WEB SOIL SURVEY – HYDROLOGIC SOIL GROUP NOAA PRECIPITATION DATA RCFC&WCD PLATE E-6.1 & E-6.2 Hydrologic Soil Group—Riverside County, Coachella Valley Area, California (CarMax Building/Parking Lot Expansion and Carwash Addition) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 1 of 437401103740150374019037402303740270374031037403503740110374015037401903740230374027037403103740350556970557010557050557090557130557170557210557250557290557330557370 556970 557010 557050 557090 557130 557170 557210 557250 557290 557330 557370 33° 48' 7'' N 116° 23' 4'' W33° 48' 7'' N116° 22' 48'' W33° 47' 58'' N 116° 23' 4'' W33° 47' 58'' N 116° 22' 48'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300 Feet 0 25 50 100 150 Meters Map Scale: 1:1,960 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Riverside County, Coachella Valley Area, California Survey Area Data: Version 13, Sep 15, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Feb 3, 2021—May 27, 2021 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group—Riverside County, Coachella Valley Area, California (CarMax Building/Parking Lot Expansion and Carwash Addition) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 2 of 4 Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CpA Coachella fine sand, 0 to 2 percent slopes A 6.2 100.0% Totals for Area of Interest 6.2 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Hydrologic Soil Group—Riverside County, Coachella Valley Area, California CarMax Building/Parking Lot Expansion and Carwash Addition Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 3 of 4 Tie-break Rule: Higher Hydrologic Soil Group—Riverside County, Coachella Valley Area, California CarMax Building/Parking Lot Expansion and Carwash Addition Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 4 of 4 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 1/4 NOAA Atlas 14, Volume 6, Version 2 Location name: Palm Desert, California, USA* Latitude: 33.8012°, Longitude: -116.3828° Elevation: 200.66 ft** * source: ESRI Maps ** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sarah Dietz, Sarah Heim, Lillian Hiner, Kazungu Maitaria, Deborah Martin, Sandra Pavlovic, Ishani Roy, Carl Trypaluk, Dale Unruh, Fenglin Yan, Michael Yekta, Tan Zhao, Geoffrey Bonnin, Daniel Brewer, Li-Chuan Chen, Tye Parzybok, John Yarchoan NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 0.055 (0.046‑0.067) 0.084 (0.070‑0.102) 0.128 (0.106‑0.156) 0.169 (0.139‑0.207) 0.233 (0.185‑0.295) 0.289 (0.225‑0.375) 0.354 (0.269‑0.471) 0.430 (0.317‑0.588) 0.549 (0.389‑0.784) 0.659 (0.450‑0.974) 10-min 0.079 (0.066‑0.096) 0.121 (0.100‑0.146) 0.184 (0.152‑0.223) 0.242 (0.199‑0.297) 0.333 (0.265‑0.423) 0.414 (0.323‑0.538) 0.508 (0.386‑0.675) 0.616 (0.455‑0.843) 0.787 (0.557‑1.12) 0.944 (0.645‑1.40) 15-min 0.096 (0.080‑0.116) 0.146 (0.121‑0.177) 0.222 (0.184‑0.270) 0.292 (0.241‑0.359) 0.403 (0.321‑0.512) 0.501 (0.390‑0.650) 0.614 (0.466‑0.817) 0.745 (0.550‑1.02) 0.952 (0.674‑1.36) 1.14 (0.780‑1.69) 30-min 0.148 (0.123‑0.180) 0.226 (0.188‑0.274) 0.344 (0.285‑0.419) 0.453 (0.373‑0.556) 0.625 (0.497‑0.793) 0.777 (0.605‑1.01) 0.951 (0.722‑1.26) 1.16 (0.852‑1.58) 1.48 (1.04‑2.11) 1.77 (1.21‑2.62) 60-min 0.222 (0.185‑0.269) 0.338 (0.282‑0.411) 0.515 (0.427‑0.627) 0.678 (0.558‑0.832) 0.935 (0.744‑1.19) 1.16 (0.905‑1.51) 1.42 (1.08‑1.89) 1.73 (1.28‑2.37) 2.21 (1.56‑3.15) 2.65 (1.81‑3.92) 2-hr 0.324 (0.270‑0.393) 0.481 (0.401‑0.584) 0.715 (0.593‑0.870) 0.927 (0.763‑1.14) 1.25 (0.997‑1.59) 1.54 (1.20‑1.99) 1.86 (1.41‑2.47) 2.22 (1.64‑3.04) 2.78 (1.96‑3.96) 3.27 (2.23‑4.83) 3-hr 0.393 (0.327‑0.476) 0.579 (0.482‑0.702) 0.852 (0.707‑1.04) 1.10 (0.905‑1.35) 1.48 (1.18‑1.88) 1.80 (1.41‑2.34) 2.17 (1.65‑2.88) 2.58 (1.91‑3.53) 3.21 (2.27‑4.58) 3.75 (2.56‑5.55) 6-hr 0.540 (0.450‑0.654) 0.795 (0.662‑0.965) 1.17 (0.970‑1.42) 1.50 (1.24‑1.85) 2.01 (1.60‑2.56) 2.45 (1.91‑3.18) 2.93 (2.23‑3.90) 3.48 (2.57‑4.76) 4.30 (3.04‑6.13) 5.00 (3.42‑7.40) 12-hr 0.638 (0.532‑0.773) 0.960 (0.799‑1.17) 1.43 (1.19‑1.75) 1.86 (1.53‑2.29) 2.51 (2.00‑3.19) 3.07 (2.39‑3.99) 3.70 (2.81‑4.92) 4.41 (3.26‑6.04) 5.49 (3.88‑7.83) 6.42 (4.38‑9.49) 24-hr 0.739 (0.655‑0.852) 1.14 (1.01‑1.32) 1.74 (1.54‑2.02) 2.28 (2.00‑2.66) 3.11 (2.63‑3.74) 3.82 (3.17‑4.70) 4.62 (3.75‑5.82) 5.53 (4.37‑7.15) 6.92 (5.25‑9.32) 8.13 (5.96‑11.3) 2-day 0.805 (0.712‑0.928) 1.27 (1.12‑1.47) 1.95 (1.72‑2.26) 2.56 (2.24‑2.98) 3.47 (2.94‑4.18) 4.25 (3.53‑5.23) 5.12 (4.15‑6.44) 6.10 (4.81‑7.88) 7.57 (5.74‑10.2) 8.83 (6.48‑12.3) 3-day 0.836 (0.740‑0.964) 1.33 (1.18‑1.54) 2.05 (1.81‑2.37) 2.69 (2.35‑3.14) 3.65 (3.09‑4.39) 4.46 (3.70‑5.48) 5.35 (4.34‑6.74) 6.36 (5.02‑8.22) 7.85 (5.96‑10.6) 9.13 (6.70‑12.7) 4-day 0.860 (0.761‑0.992) 1.38 (1.22‑1.59) 2.13 (1.88‑2.46) 2.79 (2.44‑3.26) 3.78 (3.20‑4.55) 4.62 (3.83‑5.67) 5.54 (4.49‑6.97) 6.57 (5.18‑8.49) 8.09 (6.14‑10.9) 9.40 (6.89‑13.1) 7-day 0.909 (0.805‑1.05) 1.47 (1.30‑1.70) 2.29 (2.02‑2.65) 3.01 (2.63‑3.51) 4.08 (3.46‑4.92) 4.98 (4.14‑6.12) 5.97 (4.84‑7.51) 7.06 (5.57‑9.13) 8.68 (6.58‑11.7) 10.0 (7.37‑14.0) 10-day 0.950 (0.841‑1.10) 1.55 (1.37‑1.79) 2.42 (2.13‑2.80) 3.18 (2.78‑3.71) 4.32 (3.66‑5.20) 5.27 (4.38‑6.48) 6.31 (5.12‑7.94) 7.47 (5.89‑9.65) 9.17 (6.96‑12.3) 10.6 (7.78‑14.8) 20-day 1.02 (0.904‑1.18) 1.68 (1.49‑1.94) 2.64 (2.33‑3.05) 3.49 (3.05‑4.07) 4.75 (4.03‑5.72) 5.82 (4.83‑7.15) 6.98 (5.66‑8.78) 8.26 (6.52‑10.7) 10.1 (7.70‑13.7) 11.7 (8.60‑16.3) 30-day 1.13 (1.00‑1.30) 1.86 (1.65‑2.15) 2.93 (2.59‑3.39) 3.89 (3.40‑4.53) 5.32 (4.51‑6.41) 6.52 (5.42‑8.02) 7.84 (6.36‑9.86) 9.29 (7.33‑12.0) 11.4 (8.66‑15.4) 13.2 (9.68‑18.4) 45-day 1.22 (1.08‑1.41) 2.02 (1.78‑2.33) 3.19 (2.81‑3.69) 4.24 (3.71‑4.95) 5.84 (4.95‑7.03) 7.19 (5.97‑8.83) 8.66 (7.03‑10.9) 10.3 (8.12‑13.3) 12.7 (9.61‑17.1) 14.7 (10.8‑20.4) 60-day 1.32 (1.17‑1.53) 2.18 (1.93‑2.52) 3.46 (3.05‑4.00) 4.62 (4.04‑5.38) 6.37 (5.39‑7.67) 7.86 (6.53‑9.66) 9.50 (7.70‑11.9) 11.3 (8.92‑14.6) 13.9 (10.6‑18.8) 16.2 (11.9‑22.5) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 2/4 Back to Top Maps & aerials Small scale terrain 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 3/4 Large scale terrain Large scale map Large scale aerial + – 3km 2mi + – 100km 60mi + – 100km 60mi 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 4/4 Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer + – 100km 60mi www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX E SYNTHETIC UNIT HYDROGRAPH CALCULATIONS DRAWDOWN CALCULATIONS PERCOLATION TEST SHEETS 1 & 2 1 of 6 HYDROLOGY CALCULATIONS - Using the RCFC&WCD Short Cut Unit Hydrograph Method Area Designations Existing Conditions Basin A Drainage Area (ac.)1.5700 Unit time (minutes)5 5 5 15 100 Year Storm Duration (hrs)1 3 6 24 Total Precipitation (Plates D-4.4,E-5.2, 5.4, 5.6)(in.)1.42 2.17 2.93 4.62 Or data from NOAA interactive website Soils Group A AMC index II Runoff Number (plate E-6.1)78 Plate E-6.2 Pervious Area Loss Rate (Fp)(in/hr)0.27 (AMC II) Percentage of Impervious Cover (Ai)(%) (plate E-6.3)0 Weighted Average Loss Rate (F=Fp(1-.9Ai))(in./hr.)0.27 (used for 1, 3, and 6 hour storm, the 24 hour storm uses variable maximum loss rate per plate E-1.1 (3 of 6)) Low Loss Rate Percent (%) 80 Retention Basin Percolation Rate (in/hr)1 (also used for drywell percolation rate) Percolation is taken incrementally. Basin volume is calculated using the "truncated pyramid" formula, a more conservative estimate than "averaged end areas" sometimes used (Drywell can be "zeroed out" by reducing numbers to less than .001, but should not entered as zeros or program chokes.) Drywell storage includes 40% of the 1' wide rock bed surrounding the drywell: formula (upper)*PI()*(diam/2)^2+(lower)*PI()*((diam/2)^2+0.4*((diam/2+(grav+0.4166))^2-(diam/2+0.4166)^2)) The drywell wall thickness is assumed at 5" (0.4166) and the gravel bed width is variable "grav" Drywell is zeroed out by entering .001 for values Drywell design factors Upper sec. (ft.)=0.001 Lower sec. (ft.)=0.001 Ring diam. (ft.) =0.001 Drywell lower max. (cf)=0.00 Upper max.(cf)=0.00 Gravel bed width around drwyell=1 Drywell total(cf)=0.00 Ret. Basin design (area, depth) Top =1969.45 s.f.Bot. =1969.45 s.f.Max. Depth (d)=3.275 Max. storage=6449.95 (d/3)*(bottom+top+(bottom*top)^0.50) Formulas vol=(h/3)*(bottom+top+(bottom*top)^0.50) area=bottom+(h/d)*(top-bottom)h=(vol*3)/(bottom+top+(bottom*top)^0.5)(values must be non-zero or error occurs) Outside input from:N/A 1 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 3.7 0.6305 0.2700 N/A 0.3605 0.5707 171.20 0.00 0.00 0.00 0.00 0.00 171.20 1969.45 13.68 157.52 0.08 0.00 0.00 0:10 4.8 0.8179 0.2700 N/A 0.5479 0.8674 260.22 0.00 0.00 0.00 0.00 0.00 260.22 1969.45 13.68 404.07 0.21 0.00 0.00 0:15 5.1 0.8690 0.2700 N/A 0.5990 0.9483 284.50 0.00 0.00 0.00 0.00 0.00 284.50 1969.45 13.68 674.89 0.34 0.00 0.00 0:20 4.9 0.8350 0.2700 N/A 0.5650 0.8944 268.31 0.00 0.00 0.00 0.00 0.00 268.31 1969.45 13.68 929.53 0.47 0.00 0.00 0:25 6.6 1.1246 0.2700 N/A 0.8546 1.3530 405.89 0.00 0.00 0.00 0.00 0.00 405.89 1969.45 13.68 1321.74 0.67 0.00 0.00 0:30 7.3 1.2439 0.2700 N/A 0.9739 1.5418 462.54 0.00 0.00 0.00 0.00 0.00 462.54 1969.45 13.68 1770.60 0.90 0.00 0.00 0:35 8.4 1.4314 0.2700 N/A 1.1614 1.8385 551.56 0.00 0.00 0.00 0.00 0.00 551.56 1969.45 13.68 2308.48 1.17 0.00 0.00 0:40 9 1.5336 0.2700 N/A 1.2636 2.0004 600.12 0.00 0.00 0.00 0.00 0.00 600.12 1969.45 13.68 2894.92 1.47 0.00 0.00 0:45 12.3 2.0959 0.2700 N/A 1.8259 2.8906 867.18 0.00 0.00 0.00 0.00 0.00 867.18 1969.45 13.68 3748.42 1.90 0.00 0.00 0:50 17.6 2.9990 0.2700 N/A 2.7290 4.3203 1296.09 0.00 0.00 0.00 0.00 0.00 1296.09 1969.45 13.68 5030.83 2.55 0.00 0.00 0:55 16.1 2.7434 0.2700 N/A 2.4734 3.9157 1174.70 0.00 0.00 0.00 0.00 0.00 1174.70 1969.45 13.68 6191.85 3.14 0.00 0.00 1:00 4.2 0.7157 0.2700 N/A 0.4457 0.7055 211.66 0.00 0.00 0.00 0.00 0.00 211.66 1969.45 13.68 6389.84 3.24 0.00 0.00 PEAK 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6376.17 3.24 0.00 0.00 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6362.49 3.23 0.00 0.00 1:15 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6348.81 3.22 0.00 0.00 Total volume (cf)6553.97 Total Overflow (cf)0.00 2 of 6 3 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 1.3 0.34 0.27 N/A 0.0685 0.1085 32.54 0.00 0.00 0.00 0.00 0.00 32.54 1969.45 13.68 18.86 0.01 0.00 0.00 0:10 1.3 0.34 0.27 N/A 0.0685 0.1085 32.54 0.00 0.00 0.00 0.00 0.00 32.54 1969.45 13.68 37.73 0.02 0.00 0.00 0:15 1.1 0.29 0.27 0.23 0.0573 0.0907 27.21 0.00 0.00 0.00 0.00 0.00 27.21 1969.45 13.68 51.26 0.03 0.00 0.00 0:20 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 94.86 0.05 0.00 0.00 0:25 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 138.46 0.07 0.00 0.00 0:30 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 219.16 0.11 0.00 0.00 0:35 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 262.76 0.13 0.00 0.00 0:40 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 343.46 0.17 0.00 0.00 0:45 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 424.16 0.22 0.00 0.00 0:50 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 467.76 0.24 0.00 0.00 0:55 1.6 0.42 0.27 N/A 0.1466 0.2321 69.64 0.00 0.00 0.00 0.00 0.00 69.64 1969.45 13.68 523.72 0.27 0.00 0.00 1:00 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 604.42 0.31 0.00 0.00 1:05 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 734.59 0.37 0.00 0.00 1:10 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 864.76 0.44 0.00 0.00 1:15 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 994.93 0.51 0.00 0.00 1:20 2 0.52 0.27 N/A 0.2508 0.3970 119.11 0.00 0.00 0.00 0.00 0.00 119.11 1969.45 13.68 1100.36 0.56 0.00 0.00 1:25 2.6 0.68 0.27 N/A 0.4070 0.6444 193.31 0.00 0.00 0.00 0.00 0.00 193.31 1969.45 13.68 1280.00 0.65 0.00 0.00 1:30 2.7 0.70 0.27 N/A 0.4331 0.6856 205.68 0.00 0.00 0.00 0.00 0.00 205.68 1969.45 13.68 1472.00 0.75 0.00 0.00 1:35 2.4 0.62 0.27 N/A 0.3550 0.5619 168.58 0.00 0.00 0.00 0.00 0.00 168.58 1969.45 13.68 1626.91 0.83 0.00 0.00 1:40 2.7 0.70 0.27 N/A 0.4331 0.6856 205.68 0.00 0.00 0.00 0.00 0.00 205.68 1969.45 13.68 1818.91 0.92 0.00 0.00 1:45 3.3 0.86 0.27 N/A 0.5893 0.9329 279.88 0.00 0.00 0.00 0.00 0.00 279.88 1969.45 13.68 2085.12 1.06 0.00 0.00 1:50 3.1 0.81 0.27 N/A 0.5372 0.8505 255.15 0.00 0.00 0.00 0.00 0.00 255.15 1969.45 13.68 2326.59 1.18 0.00 0.00 1:55 2.9 0.76 0.27 N/A 0.4852 0.7680 230.41 0.00 0.00 0.00 0.00 0.00 230.41 1969.45 13.68 2543.33 1.29 0.00 0.00 2:00 3 0.78 0.27 N/A 0.5112 0.8093 242.78 0.00 0.00 0.00 0.00 0.00 242.78 1969.45 13.68 2772.43 1.41 0.00 0.00 2:05 3.1 0.81 0.27 N/A 0.5372 0.8505 255.15 0.00 0.00 0.00 0.00 0.00 255.15 1969.45 13.68 3013.90 1.53 0.00 0.00 2:10 4.2 1.09 0.27 N/A 0.8237 1.3040 391.19 0.00 0.00 0.00 0.00 0.00 391.19 1969.45 13.68 3391.41 1.72 0.00 0.00 2:15 5 1.30 0.27 N/A 1.0320 1.6337 490.12 0.00 0.00 0.00 0.00 0.00 490.12 1969.45 13.68 3867.86 1.96 0.00 0.00 2:20 3.5 0.91 0.27 N/A 0.6414 1.0154 304.62 0.00 0.00 0.00 0.00 0.00 304.62 1969.45 13.68 4158.80 2.11 0.00 0.00 2:25 6.8 1.77 0.27 N/A 1.5007 2.3758 712.73 0.00 0.00 0.00 0.00 0.00 712.73 1969.45 13.68 4857.85 2.47 0.00 0.00 2:30 7.3 1.90 0.27 N/A 1.6309 2.5819 774.56 0.00 0.00 0.00 0.00 0.00 774.56 1969.45 13.68 5618.74 2.85 0.00 0.00 2:35 8.2 2.14 0.27 N/A 1.8653 2.9529 885.87 0.00 0.00 0.00 0.00 0.00 885.87 1969.45 13.68 6449.95 3.28 40.98 0.14 2:40 5.9 1.54 0.27 N/A 1.2664 2.0048 601.43 0.00 0.00 0.00 0.00 0.00 601.43 1969.45 13.68 6449.95 3.28 587.75 1.96 PEAK 2:45 2 0.52 0.27 N/A 0.2508 0.3970 119.11 0.00 0.00 0.00 0.00 0.00 119.11 1969.45 13.68 6449.95 3.28 105.43 0.35 2:50 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 6449.95 3.28 80.70 0.27 2:55 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 6449.95 3.28 80.70 0.27 3:00 0.6 0.16 0.27 0.12 0.0312 0.0495 14.84 0.00 0.00 0.00 0.00 0.00 14.84 1969.45 13.68 6449.95 3.28 1.16 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6436.27 3.27 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6422.60 3.26 0.00 0.00 3:15 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6408.92 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6395.24 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6381.57 3.24 0.00 0.00 3:30 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6367.89 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6354.21 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6340.53 3.22 0.00 0.00 Total volume (cf)7839.04 Total Overflow (cf)896.73 STORM WATER CHANNEL 3 of 6 6 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 0.5 0.18 0.27 0.14 0.0352 0.0557 16.70 0.00 0.00 0.00 0.00 0.00 16.70 1969.45 13.68 3.02 0.00 0.00 0.00 0:10 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 9.38 0.00 0.00 0.00 0:15 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 15.74 0.01 0.00 0.00 0:20 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 22.10 0.01 0.00 0.00 0:25 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 28.46 0.01 0.00 0.00 0:30 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 38.17 0.02 0.00 0.00 0:35 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 47.87 0.02 0.00 0.00 0:40 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 57.57 0.03 0.00 0.00 0:45 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 67.27 0.03 0.00 0.00 0:50 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 76.97 0.04 0.00 0.00 0:55 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 86.67 0.04 0.00 0.00 1:00 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 99.71 0.05 0.00 0.00 1:05 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 112.75 0.06 0.00 0.00 1:10 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 125.79 0.06 0.00 0.00 1:15 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 138.83 0.07 0.00 0.00 1:20 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 151.87 0.08 0.00 0.00 1:25 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 164.91 0.08 0.00 0.00 1:30 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 177.95 0.09 0.00 0.00 1:35 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 191.00 0.10 0.00 0.00 1:40 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 204.04 0.10 0.00 0.00 1:45 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 217.08 0.11 0.00 0.00 1:50 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 230.12 0.12 0.00 0.00 1:55 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 243.16 0.12 0.00 0.00 2:00 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 259.54 0.13 0.00 0.00 2:05 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 272.58 0.14 0.00 0.00 2:10 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 288.96 0.15 0.00 0.00 2:15 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 305.34 0.16 0.00 0.00 2:20 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 321.72 0.16 0.00 0.00 2:25 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 338.10 0.17 0.00 0.00 2:30 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 354.48 0.18 0.00 0.00 2:35 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 370.86 0.19 0.00 0.00 2:40 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 387.24 0.20 0.00 0.00 2:45 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 412.32 0.21 0.00 0.00 2:50 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 437.40 0.22 0.00 0.00 2:55 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 462.47 0.23 0.00 0.00 3:00 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 487.55 0.25 0.00 0.00 3:05 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 512.63 0.26 0.00 0.00 3:10 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 554.40 0.28 0.00 0.00 3:15 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 596.18 0.30 0.00 0.00 3:20 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 637.95 0.32 0.00 0.00 3:25 1.2 0.42 0.27 N/A 0.1519 0.2405 72.15 0.00 0.00 0.00 0.00 0.00 72.15 1969.45 13.68 696.43 0.35 0.00 0.00 3:30 1.3 0.46 0.27 N/A 0.1871 0.2962 88.85 0.00 0.00 0.00 0.00 0.00 88.85 1969.45 13.68 771.60 0.39 0.00 0.00 3:35 1.4 0.49 0.27 N/A 0.2222 0.3518 105.55 0.00 0.00 0.00 0.00 0.00 105.55 1969.45 13.68 863.47 0.44 0.00 0.00 3:40 1.4 0.49 0.27 N/A 0.2222 0.3518 105.55 0.00 0.00 0.00 0.00 0.00 105.55 1969.45 13.68 955.34 0.49 0.00 0.00 3:45 1.5 0.53 0.27 N/A 0.2574 0.4075 122.25 0.00 0.00 0.00 0.00 0.00 122.25 1969.45 13.68 1063.91 0.54 0.00 0.00 3:50 1.5 0.53 0.27 N/A 0.2574 0.4075 122.25 0.00 0.00 0.00 0.00 0.00 122.25 1969.45 13.68 1172.48 0.60 0.00 0.00 3:55 1.6 0.56 0.27 N/A 0.2926 0.4631 138.94 0.00 0.00 0.00 0.00 0.00 138.94 1969.45 13.68 1297.75 0.66 0.00 0.00 4:00 1.6 0.56 0.27 N/A 0.2926 0.4631 138.94 0.00 0.00 0.00 0.00 0.00 138.94 1969.45 13.68 1423.01 0.72 0.00 0.00 4:05 1.7 0.60 0.27 N/A 0.3277 0.5188 155.64 0.00 0.00 0.00 0.00 0.00 155.64 1969.45 13.68 1564.98 0.79 0.00 0.00 4:10 1.8 0.63 0.27 N/A 0.3629 0.5745 172.34 0.00 0.00 0.00 0.00 0.00 172.34 1969.45 13.68 1723.64 0.88 0.00 0.00 4 of 6 4:15 1.9 0.67 0.27 N/A 0.3980 0.6301 189.04 0.00 0.00 0.00 0.00 0.00 189.04 1969.45 13.68 1899.01 0.96 0.00 0.00 4:20 2 0.70 0.27 N/A 0.4332 0.6858 205.74 0.00 0.00 0.00 0.00 0.00 205.74 1969.45 13.68 2091.07 1.06 0.00 0.00 4:25 2.1 0.74 0.27 N/A 0.4684 0.7415 222.44 0.00 0.00 0.00 0.00 0.00 222.44 1969.45 13.68 2299.83 1.17 0.00 0.00 4:30 2.1 0.74 0.27 N/A 0.4684 0.7415 222.44 0.00 0.00 0.00 0.00 0.00 222.44 1969.45 13.68 2508.58 1.27 0.00 0.00 4:35 2.2 0.77 0.27 N/A 0.5035 0.7971 239.13 0.00 0.00 0.00 0.00 0.00 239.13 1969.45 13.68 2734.04 1.39 0.00 0.00 4:40 2.3 0.81 0.27 N/A 0.5387 0.8528 255.83 0.00 0.00 0.00 0.00 0.00 255.83 1969.45 13.68 2976.20 1.51 0.00 0.00 4:45 2.4 0.84 0.27 N/A 0.5738 0.9084 272.53 0.00 0.00 0.00 0.00 0.00 272.53 1969.45 13.68 3235.05 1.64 0.00 0.00 4:50 2.4 0.84 0.27 N/A 0.5738 0.9084 272.53 0.00 0.00 0.00 0.00 0.00 272.53 1969.45 13.68 3493.91 1.77 0.00 0.00 4:55 2.5 0.88 0.27 N/A 0.6090 0.9641 289.23 0.00 0.00 0.00 0.00 0.00 289.23 1969.45 13.68 3769.46 1.91 0.00 0.00 5:00 2.6 0.91 0.27 N/A 0.6442 1.0198 305.93 0.00 0.00 0.00 0.00 0.00 305.93 1969.45 13.68 4061.71 2.06 0.00 0.00 5:05 3.1 1.09 0.27 N/A 0.8200 1.2981 389.42 0.00 0.00 0.00 0.00 0.00 389.42 1969.45 13.68 4437.45 2.25 0.00 0.00 5:10 3.6 1.27 0.27 N/A 0.9958 1.5764 472.91 0.00 0.00 0.00 0.00 0.00 472.91 1969.45 13.68 4896.69 2.49 0.00 0.00 5:15 3.9 1.37 0.27 N/A 1.1012 1.7434 523.01 0.00 0.00 0.00 0.00 0.00 523.01 1969.45 13.68 5406.02 2.74 0.00 0.00 5:20 4.2 1.48 0.27 N/A 1.2067 1.9103 573.10 0.00 0.00 0.00 0.00 0.00 573.10 1969.45 13.68 5965.44 3.03 0.00 0.00 5:25 4.7 1.65 0.27 N/A 1.3825 2.1886 656.59 0.00 0.00 0.00 0.00 0.00 656.59 1969.45 13.68 6449.95 3.28 158.41 0.53 5:30 5.6 1.97 0.27 N/A 1.6990 2.6896 806.88 0.00 0.00 0.00 0.00 0.00 806.88 1969.45 13.68 6449.95 3.28 793.20 2.64 PEAK 5:35 1.9 0.67 0.27 N/A 0.3980 0.6301 189.04 0.00 0.00 0.00 0.00 0.00 189.04 1969.45 13.68 6449.95 3.28 175.36 0.58 5:40 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 6449.95 3.28 16.38 0.05 5:45 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 6449.95 3.28 6.36 0.02 5:50 0.5 0.18 0.27 0.14 0.0352 0.0557 16.70 0.00 0.00 0.00 0.00 0.00 16.70 1969.45 13.68 6449.95 3.28 3.02 0.01 5:55 0.3 0.11 0.27 0.08 0.0211 0.0334 10.02 0.00 0.00 0.00 0.00 0.00 10.02 1969.45 13.68 6446.29 3.27 0.00 0.00 6:00 0.2 0.07 0.27 0.06 0.0141 0.0223 6.68 0.00 0.00 0.00 0.00 0.00 6.68 1969.45 13.68 6439.29 3.27 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6425.62 3.26 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6411.94 3.26 0.00 0.00 6:15 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6398.26 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6384.59 3.24 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6370.91 3.23 0.00 0.00 6:30 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6357.23 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6343.56 3.22 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6329.88 3.21 0.00 0.00 6:45 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6316.20 3.21 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6302.53 3.20 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6288.85 3.19 0.00 0.00 7:00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6275.17 3.19 0.00 0.00 Total volume (cf)8576.76 Total Overflow (cf)1152.74 STORM WATER CHANNEL 5 of 6 24 Hour Storm in 15 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:15 0.2 0.04 0.47 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 10.53 0.00 0.00 0.00 0.00 0:30 0.3 0.06 0.47 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 0:45 0.3 0.06 0.46 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:00 0.4 0.07 0.46 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 1:15 0.3 0.06 0.45 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:30 0.3 0.06 0.45 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:45 0.3 0.06 0.44 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 2:00 0.4 0.07 0.44 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:15 0.4 0.07 0.43 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:30 0.4 0.07 0.43 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:45 0.5 0.09 0.42 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:00 0.5 0.09 0.42 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:15 0.5 0.09 0.41 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:30 0.5 0.09 0.40 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:45 0.5 0.09 0.40 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 4:00 0.6 0.11 0.39 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 31.60 0.00 0.00 0.00 0.00 4:15 0.6 0.11 0.39 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 31.60 0.00 0.00 0.00 0.00 4:30 0.7 0.13 0.38 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 4:45 0.7 0.13 0.38 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 5:00 0.8 0.15 0.37 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 1.10 0.00 0.00 0.00 5:15 0.6 0.11 0.37 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 41.03 0.00 0.00 0.00 0.00 5:30 0.7 0.13 0.37 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 5:45 0.8 0.15 0.36 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 1.10 0.00 0.00 0.00 6:00 0.8 0.15 0.36 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 2.20 0.00 0.00 0.00 6:15 0.9 0.17 0.35 0.13 0.0333 0.0527 47.39 0.00 0.00 0.00 0.00 0.00 47.39 1969.45 41.03 8.56 0.00 0.00 0.00 6:30 0.9 0.17 0.35 0.13 0.0333 0.0527 47.39 0.00 0.00 0.00 0.00 0.00 47.39 1969.45 41.03 14.92 0.01 0.00 0.00 6:45 1 0.18 0.34 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 26.55 0.01 0.00 0.00 7:00 1 0.18 0.34 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 38.18 0.02 0.00 0.00 7:15 1 0.18 0.33 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 49.81 0.03 0.00 0.00 7:30 1.1 0.20 0.33 0.16 0.0407 0.0644 57.93 0.00 0.00 0.00 0.00 0.00 57.93 1969.45 41.03 66.71 0.03 0.00 0.00 7:45 1.2 0.22 0.32 0.18 0.0444 0.0702 63.19 0.00 0.00 0.00 0.00 0.00 63.19 1969.45 41.03 88.87 0.05 0.00 0.00 8:00 1.3 0.24 0.32 0.19 0.0480 0.0761 68.46 0.00 0.00 0.00 0.00 0.00 68.46 1969.45 41.03 116.29 0.06 0.00 0.00 8:15 1.5 0.28 0.31 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 154.25 0.08 0.00 0.00 8:30 1.5 0.28 0.31 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 192.21 0.10 0.00 0.00 8:45 1.6 0.30 0.31 0.24 0.0591 0.0936 84.26 0.00 0.00 0.00 0.00 0.00 84.26 1969.45 41.03 235.44 0.12 0.00 0.00 9:00 1.7 0.31 0.30 0.25 0.0628 0.0995 89.52 0.00 0.00 0.00 0.00 0.00 89.52 1969.45 41.03 283.93 0.14 0.00 0.00 9:15 1.9 0.35 0.30 0.28 0.0702 0.1112 100.05 0.00 0.00 0.00 0.00 0.00 100.05 1969.45 41.03 342.95 0.17 0.00 0.00 9:30 2 0.37 0.29 N/A 0.0768 0.1216 109.45 0.00 0.00 0.00 0.00 0.00 109.45 1969.45 41.03 411.37 0.21 0.00 0.00 9:45 2.1 0.39 0.29 N/A 0.0995 0.1575 141.76 0.00 0.00 0.00 0.00 0.00 141.76 1969.45 41.03 512.10 0.26 0.00 0.00 10:00 2.2 0.41 0.28 N/A 0.1221 0.1933 174.01 0.00 0.00 0.00 0.00 0.00 174.01 1969.45 41.03 645.07 0.33 0.00 0.00 10:15 1.5 0.28 0.28 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 683.03 0.35 0.00 0.00 10:30 1.5 0.28 0.28 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 720.99 0.37 0.00 0.00 10:45 2 0.37 0.27 N/A 0.0974 0.1542 138.76 0.00 0.00 0.00 0.00 0.00 138.76 1969.45 41.03 818.72 0.42 0.00 0.00 11:00 2 0.37 0.27 N/A 0.1014 0.1605 144.45 0.00 0.00 0.00 0.00 0.00 144.45 1969.45 41.03 922.15 0.47 0.00 0.00 11:15 1.9 0.35 0.26 N/A 0.0869 0.1375 123.75 0.00 0.00 0.00 0.00 0.00 123.75 1969.45 41.03 1004.86 0.51 0.00 0.00 11:30 1.9 0.35 0.26 N/A 0.0908 0.1437 129.32 0.00 0.00 0.00 0.00 0.00 129.32 1969.45 41.03 1093.15 0.56 0.00 0.00 11:45 1.7 0.31 0.26 0.25 0.0628 0.0995 89.52 0.00 0.00 0.00 0.00 0.00 89.52 1969.45 41.03 1141.64 0.58 0.00 0.00 12:00 1.8 0.33 0.25 N/A 0.0800 0.1266 113.94 0.00 0.00 0.00 0.00 0.00 113.94 1969.45 41.03 1214.55 0.62 0.00 0.00 12:15 2.5 0.46 0.25 N/A 0.2131 0.3374 303.63 0.00 0.00 0.00 0.00 0.00 303.63 1969.45 41.03 1477.15 0.75 0.00 0.00 12:30 2.6 0.48 0.25 N/A 0.2353 0.3725 335.28 0.00 0.00 0.00 0.00 0.00 335.28 1969.45 41.03 1771.40 0.90 0.00 0.00 6 of 6 12:45 2.8 0.52 0.24 N/A 0.2760 0.4369 393.20 0.00 0.00 0.00 0.00 0.00 393.20 1969.45 41.03 2123.56 1.08 0.00 0.00 13:00 2.9 0.54 0.24 N/A 0.2981 0.4719 424.72 0.00 0.00 0.00 0.00 0.00 424.72 1969.45 41.03 2507.25 1.27 0.00 0.00 13:15 3.4 0.63 0.23 N/A 0.3941 0.6239 561.50 0.00 0.00 0.00 0.00 0.00 561.50 1969.45 41.03 3027.72 1.54 0.00 0.00 13:30 3.4 0.63 0.23 N/A 0.3976 0.6295 566.56 0.00 0.00 0.00 0.00 0.00 566.56 1969.45 41.03 3553.24 1.80 0.00 0.00 13:45 2.3 0.43 0.23 N/A 0.1979 0.3133 281.93 0.00 0.00 0.00 0.00 0.00 281.93 1969.45 41.03 3794.14 1.93 0.00 0.00 14:00 2.3 0.43 0.22 N/A 0.2013 0.3187 286.86 0.00 0.00 0.00 0.00 0.00 286.86 1969.45 41.03 4039.97 2.05 0.00 0.00 14:15 2.7 0.50 0.22 N/A 0.2787 0.4412 397.04 0.00 0.00 0.00 0.00 0.00 397.04 1969.45 41.03 4395.98 2.23 0.00 0.00 14:30 2.6 0.48 0.22 N/A 0.2636 0.4172 375.51 0.00 0.00 0.00 0.00 0.00 375.51 1969.45 41.03 4730.46 2.40 0.00 0.00 14:45 2.6 0.48 0.21 N/A 0.2669 0.4225 380.23 0.00 0.00 0.00 0.00 0.00 380.23 1969.45 41.03 5069.67 2.57 0.00 0.00 15:00 2.5 0.46 0.21 N/A 0.2517 0.3984 358.56 0.00 0.00 0.00 0.00 0.00 358.56 1969.45 41.03 5387.20 2.74 0.00 0.00 15:15 2.4 0.44 0.21 N/A 0.2364 0.3742 336.82 0.00 0.00 0.00 0.00 0.00 336.82 1969.45 41.03 5682.98 2.89 0.00 0.00 15:30 2.3 0.43 0.20 N/A 0.2211 0.3500 315.00 0.00 0.00 0.00 0.00 0.00 315.00 1969.45 41.03 5956.96 3.02 0.00 0.00 15:45 1.9 0.35 0.20 N/A 0.1503 0.2379 214.13 0.00 0.00 0.00 0.00 0.00 214.13 1969.45 41.03 6130.05 3.11 0.00 0.00 16:00 1.9 0.35 0.20 N/A 0.1534 0.2428 218.49 0.00 0.00 0.00 0.00 0.00 218.49 1969.45 41.03 6307.52 3.20 0.00 0.00 PEAK 16:15 0.4 0.07 0.19 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6287.55 3.19 0.00 0.00 16:30 0.4 0.07 0.19 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6267.58 3.18 0.00 0.00 16:45 0.3 0.06 0.19 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6242.35 3.17 0.00 0.00 17:00 0.3 0.06 0.19 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6217.12 3.16 0.00 0.00 17:15 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6202.42 3.15 0.00 0.00 17:30 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6187.72 3.14 0.00 0.00 17:45 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6173.02 3.13 0.00 0.00 18:00 0.4 0.07 0.18 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6153.05 3.12 0.00 0.00 18:15 0.4 0.07 0.17 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6133.08 3.11 0.00 0.00 18:30 0.4 0.07 0.17 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6113.12 3.10 0.00 0.00 18:45 0.3 0.06 0.17 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6087.89 3.09 0.00 0.00 19:00 0.2 0.04 0.17 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 6057.39 3.08 0.00 0.00 19:15 0.3 0.06 0.16 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6032.15 3.06 0.00 0.00 19:30 0.4 0.07 0.16 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6012.19 3.05 0.00 0.00 19:45 0.3 0.06 0.16 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5986.96 3.04 0.00 0.00 20:00 0.2 0.04 0.16 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5956.46 3.02 0.00 0.00 20:15 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5931.23 3.01 0.00 0.00 20:30 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5905.99 3.00 0.00 0.00 20:45 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5880.76 2.99 0.00 0.00 21:00 0.2 0.04 0.15 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5850.26 2.97 0.00 0.00 21:15 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5825.03 2.96 0.00 0.00 21:30 0.2 0.04 0.15 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5794.53 2.94 0.00 0.00 21:45 0.3 0.06 0.14 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5769.30 2.93 0.00 0.00 22:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5738.80 2.91 0.00 0.00 22:15 0.3 0.06 0.14 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5713.57 2.90 0.00 0.00 22:30 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5683.07 2.89 0.00 0.00 22:45 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5652.57 2.87 0.00 0.00 23:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5622.07 2.85 0.00 0.00 23:15 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5591.58 2.84 0.00 0.00 23:30 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5561.08 2.82 0.00 0.00 23:45 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5530.58 2.81 0.00 0.00 24:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5500.08 2.79 0.00 0.00 0 0.00 0.14 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 41.03 5459.05 2.77 0.00 0.00 Total volume (cf)9089.24 Total Overflow (cf)0.00 8/11/2022 PALM DESERT CARMAX BUILDING/PARKING LOT EXPANSION AND CARWASH ADDITION DRAW-DOWN TIME CHECK UNDERGROUND RETENTION BASIN DRAW-DOWN TIME BASIN Total Dead Storage Volume Infiltration Rate Infilitration Safety Factor Design Infiltration Rate (Pdesign) Design Infiltration Rate Used*Total Area Total Infiltration Draw-Down Time -(ft3)(in/hr) - (in/hr) (in/hr) (sf) (cfs) (hrs) A 6,448 5.38 3 1.79 1.00 1,967 0.046 39.34 DRAW DOWN CHECK GOOD * Based on the infiltration rate of 1 in/hr per Palm Desert maximum (with supported testing). 6.85 3/8/2022 6 KTM 3 Sand 0 to 6.85 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 5.22 6.8 18.96 2 25 3.85 6.8 35.4 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 3.40 6.45 36.60 0.27 2 10 3.60 6.12 30.24 0.33 3 10 2.40 5.63 38.76 0.26 4 10 3.13 5.50 28.44 0.35 5 10 2.00 5.32 39.84 0.25 6 10 2.54 5.19 31.80 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 67.78 76.19 64.82 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 113.19 90.64 83.02 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-1 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 64.820.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.51 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  6.75 3/8/2022 6 KTM 3 Sand 0 to 6.75 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 3.6 6.6 36 2 25 2.8 6.6 45.6 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 2.32 5.30 35.76 0.28 2 10 2.68 5.10 29.04 0.34 3 10 2.10 4.82 32.64 0.31 4 10 2.70 4.94 26.88 0.37 5 10 2.43 5.05 31.44 0.32 6 10 2.30 4.99 32.28 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 55.78 63.58 63.36 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 73.97 61.68 60.59 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-2 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 63.360.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.38 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX F ADS UNDERGROUND RETENTION BASIN DESIGN SHEETS User Inputs Chamber Model: MC-3500 Outlet Control Structure: Yes Project Name: 190260 - CarMax Ex- pansion (3 Rows/In- terior Outlet) Engineer: Carmen Graciano Project Location: California Measurement Type: Imperial Required Storage Volume: 6213.17 cubic ft. Stone Porosity: 40% Stone Foundation Depth: 9 in. Stone Above Chambers: 12 in. Average Cover Over Chambers: 18 in. Design Constraint Dimensions:(23 ft. x 116 ft.) Results System Volume and Bed Size Installed Storage Volume: 6448.45 cubic ft. Storage Volume Per Chamber: 109.90 cubic ft. Number Of Chambers Required: 31 Number Of End Caps Required: 8 Chamber Rows: 3 Maximum Length:88.51 ft. Maximum Width: 22.25 ft. Approx. Bed Size Required: 1969.45 square ft. System Components Amount Of Stone Required: 271 cubic yards Volume Of Excavation (Not Including Fill): 402 cubic yards Total Non-woven Geotextile Required:688 square yards Woven Geotextile Required (excluding Isolator Row): 34 square yards Woven Geotextile Required (Isolator Row): 97 square yards Total Woven Geotextile Required:130 square yards Advanced Drainage Systems, Inc.FOR STORMTECHINSTALLATION INSTRUCTIONSVISIT OUR APPSiteAssistMC-3500 STORMTECH CHAMBER SPECIFICATIONS1.CHAMBERS SHALL BE STORMTECH MC-3500.2.CHAMBERS SHALL BE ARCH-SHAPED AND SHALL BE MANUFACTURED FROM VIRGIN, IMPACT-MODIFIED POLYPROPYLENECOPOLYMERS.3.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATEDWALL STORMWATER COLLECTION CHAMBERS" CHAMBER CLASSIFICATION 45x76 DESIGNATION SS.4.CHAMBER ROWS SHALL PROVIDE CONTINUOUS, UNOBSTRUCTED INTERNAL SPACE WITH NO INTERNAL SUPPORTS THAT WOULDIMPEDE FLOW OR LIMIT ACCESS FOR INSPECTION.5.THE STRUCTURAL DESIGN OF THE CHAMBERS, THE STRUCTURAL BACKFILL, AND THE INSTALLATION REQUIREMENTS SHALL ENSURETHAT THE LOAD FACTORS SPECIFIED IN THE AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS, SECTION 12.12, ARE MET FOR: 1)LONG-DURATION DEAD LOADS AND 2) SHORT-DURATION LIVE LOADS, BASED ON THE AASHTO DESIGN TRUCK WITH CONSIDERATIONFOR IMPACT AND MULTIPLE VEHICLE PRESENCES.6.CHAMBERS SHALL BE DESIGNED, TESTED AND ALLOWABLE LOAD CONFIGURATIONS DETERMINED IN ACCORDANCE WITH ASTM F2787,"STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".LOAD CONFIGURATIONS SHALL INCLUDE: 1) INSTANTANEOUS (<1 MIN) AASHTO DESIGN TRUCK LIVE LOAD ON MINIMUM COVER 2)MAXIMUM PERMANENT (75-YR) COVER LOAD AND 3) ALLOWABLE COVER WITH PARKED (1-WEEK) AASHTO DESIGN TRUCK.7.REQUIREMENTS FOR HANDLING AND INSTALLATION:·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKINGSTACKING LUGS.·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESSTHAN 3”.·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BEGREATER THAN OR EQUAL TO 450 LBS/FT/%. THE ASC IS DEFINED IN SECTION 6.2.8 OF ASTM F2418. AND b) TO RESIST CHAMBERDEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCEDFROM REFLECTIVE GOLD OR YELLOW COLORS.8.ONLY CHAMBERS THAT ARE APPROVED BY THE SITE DESIGN ENGINEER WILL BE ALLOWED. UPON REQUEST BY THE SITE DESIGNENGINEER OR OWNER, THE CHAMBER MANUFACTURER SHALL SUBMIT A STRUCTURAL EVALUATION FOR APPROVAL BEFOREDELIVERING CHAMBERS TO THE PROJECT SITE AS FOLLOWS:·THE STRUCTURAL EVALUATION SHALL BE SEALED BY A REGISTERED PROFESSIONAL ENGINEER.·THE STRUCTURAL EVALUATION SHALL DEMONSTRATE THAT THE SAFETY FACTORS ARE GREATER THAN OR EQUAL TO 1.95 FORDEAD LOAD AND 1.75 FOR LIVE LOAD, THE MINIMUM REQUIRED BY ASTM F2787 AND BY SECTIONS 3 AND 12.12 OF THE AASHTOLRFD BRIDGE DESIGN SPECIFICATIONS FOR THERMOPLASTIC PIPE.·THE TEST DERIVED CREEP MODULUS AS SPECIFIED IN ASTM F2418 SHALL BE USED FOR PERMANENT DEAD LOAD DESIGNEXCEPT THAT IT SHALL BE THE 75-YEAR MODULUS USED FOR DESIGN.9.CHAMBERS AND END CAPS SHALL BE PRODUCED AT AN ISO 9001 CERTIFIED MANUFACTURING FACILITY.IMPORTANT - NOTES FOR THE BIDDING AND INSTALLATION OF MC-3500 CHAMBER SYSTEM1.STORMTECH MC-3500 CHAMBERS SHALL NOT BE INSTALLED UNTIL THE MANUFACTURER'S REPRESENTATIVE HAS COMPLETED APRE-CONSTRUCTION MEETING WITH THE INSTALLERS.2.STORMTECH MC-3500 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".3.CHAMBERS ARE NOT TO BE BACKFILLED WITH A DOZER OR AN EXCAVATOR SITUATED OVER THE CHAMBERS.STORMTECH RECOMMENDS 3 BACKFILL METHODS:·STONESHOOTER LOCATED OFF THE CHAMBER BED.·BACKFILL AS ROWS ARE BUILT USING AN EXCAVATOR ON THE FOUNDATION STONE OR SUBGRADE.·BACKFILL FROM OUTSIDE THE EXCAVATION USING A LONG BOOM HOE OR EXCAVATOR.4.THE FOUNDATION STONE SHALL BE LEVELED AND COMPACTED PRIOR TO PLACING CHAMBERS.5.JOINTS BETWEEN CHAMBERS SHALL BE PROPERLY SEATED PRIOR TO PLACING STONE.6.MAINTAIN MINIMUM - 6" (150 mm) SPACING BETWEEN THE CHAMBER ROWS.7.INLET AND OUTLET MANIFOLDS MUST BE INSERTED A MINIMUM OF 12" (300 mm) INTO CHAMBER END CAPS.8.EMBEDMENT STONE SURROUNDING CHAMBERS MUST BE A CLEAN, CRUSHED, ANGULAR STONE MEETING THE AASHTO M43 DESIGNATION OF #3OR #4.9.STONE MUST BE PLACED ON THE TOP CENTER OF THE CHAMBER TO ANCHOR THE CHAMBERS IN PLACE AND PRESERVE ROW SPACING.10.THE CONTRACTOR MUST REPORT ANY DISCREPANCIES WITH CHAMBER FOUNDATION MATERIALS BEARING CAPACITIES TO THE SITE DESIGNENGINEER.11.ADS RECOMMENDS THE USE OF "FLEXSTORM CATCH IT" INSERTS DURING CONSTRUCTION FOR ALL INLETS TO PROTECT THE SUBSURFACESTORMWATER MANAGEMENT SYSTEM FROM CONSTRUCTION SITE RUNOFF.NOTES FOR CONSTRUCTION EQUIPMENT1.STORMTECH MC-3500 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".2.THE USE OF EQUIPMENT OVER MC-3500 CHAMBERS IS LIMITED:·NO EQUIPMENT IS ALLOWED ON BARE CHAMBERS.·NO RUBBER TIRED LOADER, DUMP TRUCK, OR EXCAVATORS ARE ALLOWED UNTIL PROPER FILL DEPTHS ARE REACHED IN ACCORDANCEWITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".·WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT CAN BE FOUND IN THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".3.FULL 36" (900 mm) OF STABILIZED COVER MATERIALS OVER THE CHAMBERS IS REQUIRED FOR DUMP TRUCK TRAVEL OR DUMPING.USE OF A DOZER TO PUSH EMBEDMENT STONE BETWEEN THE ROWS OF CHAMBERS MAY CAUSE DAMAGE TO CHAMBERS AND IS NOT AN ACCEPTABLEBACKFILL METHOD. ANY CHAMBERS DAMAGED BY USING THE "DUMP AND PUSH" METHOD ARE NOT COVERED UNDER THE STORMTECH STANDARDWARRANTY.CONTACT STORMTECH AT 1-888-892-2694 WITH ANY QUESTIONS ON INSTALLATION REQUIREMENTS OR WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT.©2022 ADS, INC.PROJECT INFORMATIONADS SALES REPPROJECT NO.ENGINEERED PRODUCTMANAGER190260 - CARMAX EXPANSION (3 ROWS/INTERIOR OUTLET)PALM DESERT, CA StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber System4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF26NOTES•MANIFOLD SIZE TO BE DETERMINED BY SITE DESIGN ENGINEER. SEE TECH NOTE #6.32 FOR MANIFOLD SIZING GUIDANCE.•DUE TO THE ADAPTATION OF THIS CHAMBER SYSTEM TO SPECIFIC SITE AND DESIGN CONSTRAINTS, IT MAY BE NECESSARY TO CUT AND COUPLE ADDITIONAL PIPE TO STANDARD MANIFOLDCOMPONENTS IN THE FIELD.•THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.•THIS CHAMBER SYSTEM WAS DESIGNED WITHOUT SITE-SPECIFIC INFORMATION ON SOIL CONDITIONS OR BEARING CAPACITY. THE SITE DESIGN ENGINEER IS RESPONSIBLE FORDETERMININGTHE SUITABILITY OF THE SOIL AND PROVIDING THE BEARING CAPACITY OF THE INSITU SOILS. THE BASE STONE DEPTH MAY BE INCREASED OR DECREASED ONCE THIS INFORMATION ISPROVIDED.•NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE.CONCEPTUAL ELEVATIONSMAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):12.50MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):6.50MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):6.00MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):6.00MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):6.00TOP OF STONE:5.50TOP OF MC-3500 CHAMBER:4.5012" x 12" TOP MANIFOLD INVERT:2.9524" ISOLATOR ROW PLUS INVERT:0.9218" BOTTOM CONNECTION INVERT:0.90BOTTOM OF MC-3500 CHAMBER:0.75BOTTOM OF STONE:0.00PROPOSED LAYOUT31STORMTECH MC-3500 CHAMBERS8STORMTECH MC-3500 END CAPS12STONE ABOVE (in)9STONE BELOW (in)40STONE VOID6450INSTALLED SYSTEM VOLUME (CF)(PERIMETER STONE INCLUDED)(COVER STONE INCLUDED)(BASE STONE INCLUDED)1969SYSTEM AREA (SF)221.5SYSTEM PERIMETER (ft)*INVERT ABOVE BASE OF CHAMBERMAX FLOWINVERT*DESCRIPTIONITEM ONLAYOUTPART TYPE2.06"24" BOTTOM CORED END CAP, PART#: MC3500IEPP24BC / TYP OF ALL 24" BOTTOMCONNECTIONS AND ISOLATOR PLUS ROWSAPREFABRICATED END CAP26.36"12" TOP CORED END CAP, PART#: MC3500IEPP12T / TYP OF ALL 12" TOP CONNECTIONSBPREFABRICATED END CAP1.77"18" BOTTOM CORED END CAP, PART#: MC3500IEPP18BC / TYP OF ALL 18" BOTTOMCONNECTIONSCPREFABRICATED END CAPINSTALL FLAMP ON 24" ACCESS PIPE / PART#: MC350024RAMPDFLAMP26.36"12" x 12" TOP MANIFOLD, ADS N-12EMANIFOLD5.0 CFS IN30" DIAMETER (24.00" SUMP MIN)FNYLOPLAST (INLET W/ ISOPLUS ROW)4.0 CFS OUT30" DIAMETER (DESIGN BY ENGINEER)GNYLOPLAST (OUTLET)ISOLATOR ROW PLUS(SEE DETAIL)PLACE MINIMUM 17.50' OF ADSPLUS175 WOVEN GEOTEXTILE OVER BEDDINGSTONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALLCHAMBER INLET ROWSBED LIMITS20'10'088.51'22.25'82.58'20.25'EGBCDAF StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemACCEPTABLE FILL MATERIALS: STORMTECH MC-3500 CHAMBER SYSTEMSPLEASE NOTE:1.THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED, ANGULAR NO. 4 (AASHTO M43) STONE".2.STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 9" (230 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR.3.WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTION EQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FORCOMPACTION REQUIREMENTS.4.ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL REQUIREMENTS OF LAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION.NOTES:1.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS" CHAMBER CLASSIFICATION 45x76DESIGNATION SS.2.MC-3500 CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".3.THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE WITH CONSIDERATIONFOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS.4.PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS.5.REQUIREMENTS FOR HANDLING AND INSTALLATION:·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKING STACKING LUGS.·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESS THAN 3”.·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BE GREATER THAN OR EQUAL TO 450 LBS/FT/%. THE ASC IS DEFINED IN SECTION 6.2.8 OFASTM F2418. AND b) TO RESIST CHAMBER DEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCED FROM REFLECTIVE GOLD OR YELLOWCOLORS.MATERIAL LOCATIONDESCRIPTIONAASHTO MATERIALCLASSIFICATIONSCOMPACTION / DENSITY REQUIREMENTDFINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTS FROM THE TOP OF THE 'C'LAYER TO THE BOTTOM OF FLEXIBLE PAVEMENT OR UNPAVED FINISHEDGRADE ABOVE. NOTE THAT PAVEMENT SUBBASE MAY BE PART OF THE 'D'LAYERANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PER ENGINEER'S PLANS.CHECK PLANS FOR PAVEMENT SUBGRADE REQUIREMENTS.N/APREPARE PER SITE DESIGN ENGINEER'S PLANS. PAVEDINSTALLATIONS MAY HAVE STRINGENT MATERIAL ANDPREPARATION REQUIREMENTS.CINITIAL FILL: FILL MATERIAL FOR LAYER 'C' STARTS FROM THE TOP OF THEEMBEDMENT STONE ('B' LAYER) TO 24" (600 mm) ABOVE THE TOP OF THECHAMBER. NOTE THAT PAVEMENT SUBBASE MAY BE A PART OF THE 'C'LAYER.GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35% FINES ORPROCESSED AGGREGATE. MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEU OF THISLAYER.AASHTO M145¹A-1, A-2-4, A-3ORAASHTO M43¹3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89, 9, 10BEGIN COMPACTIONS AFTER 24" (600 mm) OF MATERIAL OVERTHE CHAMBERS IS REACHED. COMPACT ADDITIONAL LAYERS IN12" (300 mm) MAX LIFTS TO A MIN. 95% PROCTOR DENSITY FORWELL GRADED MATERIAL AND 95% RELATIVE DENSITY FORPROCESSED AGGREGATE MATERIALS.BEMBEDMENT STONE: FILL SURROUNDING THE CHAMBERS FROM THEFOUNDATION STONE ('A' LAYER) TO THE 'C' LAYER ABOVE.CLEAN, CRUSHED, ANGULAR STONEAASHTO M43¹3, 4AFOUNDATION STONE: FILL BELOW CHAMBERS FROM THE SUBGRADE UP TOTHE FOOT (BOTTOM) OF THE CHAMBER.CLEAN, CRUSHED, ANGULAR STONEAASHTO M43¹3, 4PLATE COMPACT OR ROLL TO ACHIEVE A FLAT SURFACE.2,345"(1140 mm)18"(450 mm) MIN*8'(2.4 m)MAX12" (300 mm) MIN77" (1950 mm)12" (300 mm) MIN6"(150 mm) MINDEPTH OF STONE TO BE DETERMINEDBY SITE DESIGN ENGINEER 9" (230 mm) MINDCBA*TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVEDINSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR,INCREASE COVER TO 24" (600 mm).6" (150 mm) MINPERIMETER STONE(SEE NOTE 4)EXCAVATION WALL(CAN BE SLOPED OR VERTICAL)MC-3500END CAPSUBGRADE SOILS(SEE NOTE 3)PAVEMENT LAYER (DESIGNEDBY SITE DESIGN ENGINEER)NO COMPACTION REQUIRED.ADS GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE ALLAROUND CLEAN, CRUSHED, ANGULAR STONE IN A & B LAYERS4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF36 StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemINSPECTION & MAINTENANCESTEP 1)INSPECT ISOLATOR ROW PLUS FOR SEDIMENTA.INSPECTION PORTS (IF PRESENT)A.1.REMOVE/OPEN LID ON NYLOPLAST INLINE DRAINA.2.REMOVE AND CLEAN FLEXSTORM FILTER IF INSTALLEDA.3.USING A FLASHLIGHT AND STADIA ROD, MEASURE DEPTH OF SEDIMENT AND RECORD ON MAINTENANCE LOGA.4.LOWER A CAMERA INTO ISOLATOR ROW PLUS FOR VISUAL INSPECTION OF SEDIMENT LEVELS (OPTIONAL)A.5.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.B.ALL ISOLATOR PLUS ROWSB.1.REMOVE COVER FROM STRUCTURE AT UPSTREAM END OF ISOLATOR ROW PLUSB.2.USING A FLASHLIGHT, INSPECT DOWN THE ISOLATOR ROW PLUS THROUGH OUTLET PIPEi)MIRRORS ON POLES OR CAMERAS MAY BE USED TO AVOID A CONFINED SPACE ENTRYii)FOLLOW OSHA REGULATIONS FOR CONFINED SPACE ENTRY IF ENTERING MANHOLEB.3.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.STEP 2)CLEAN OUT ISOLATOR ROW PLUS USING THE JETVAC PROCESSA.A FIXED CULVERT CLEANING NOZZLE WITH REAR FACING SPREAD OF 45" (1.1 m) OR MORE IS PREFERREDB.APPLY MULTIPLE PASSES OF JETVAC UNTIL BACKFLUSH WATER IS CLEANC.VACUUM STRUCTURE SUMP AS REQUIREDSTEP 3)REPLACE ALL COVERS, GRATES, FILTERS, AND LIDS; RECORD OBSERVATIONS AND ACTIONS.STEP 4)INSPECT AND CLEAN BASINS AND MANHOLES UPSTREAM OF THE STORMTECH SYSTEM.NOTES1.INSPECT EVERY 6 MONTHS DURING THE FIRST YEAR OF OPERATION. ADJUST THE INSPECTION INTERVAL BASED ON PREVIOUSOBSERVATIONS OF SEDIMENT ACCUMULATION AND HIGH WATER ELEVATIONS.2.CONDUCT JETTING AND VACTORING ANNUALLY OR WHEN INSPECTION SHOWS THAT MAINTENANCE IS NECESSARY.24" (600 mm) HDPE ACCESS PIPE REQUIREDUSE FACTORY PARTIAL CUT END CAP PART #:MC3500IEPP24BC OR MC3500IEPP24BWONE LAYER OF ADSPLUS175 WOVEN GEOTEXTILE BETWEENFOUNDATION STONE AND CHAMBERS8.25' (2.51 m) MIN WIDE CONTINUOUS FABRIC WITHOUT SEAMSCOVER PIPE CONNECTION TO ENDCAP WITH ADS GEOSYNTHETICS 601TNON-WOVEN GEOTEXTILEMC-3500 CHAMBERMC-3500 END CAPMC-3500 ISOLATOR ROW PLUS DETAILNTSOPTIONAL INSPECTION PORTSTORMTECH HIGHLY RECOMMENDSFLEXSTORM INSERTS IN ANY UPSTREAMSTRUCTURES WITH OPEN GRATESELEVATED BYPASS MANIFOLDINSTALL FLAMP ON 24" (600 mm) ACCESS PIPEPART #: MC350024RAMPSUMP DEPTH TBD BYSITE DESIGN ENGINEER(24" [600 mm] MIN RECOMMENDED)NYLOPLAST4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF46 StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemMC-SERIES END CAP INSERTION DETAILNTSNOTE: MANIFOLD STUB MUST BE LAID HORIZONTALFOR A PROPER FIT IN END CAP OPENING.MANIFOLD HEADERMANIFOLD STUBSTORMTECH END CAPMANIFOLD HEADERMANIFOLD STUB12" (300 mm)MIN SEPARATION12" (300 mm) MIN INSERTION12" (300 mm)MIN SEPARATION12" (300 mm)MIN INSERTIONPART #STUBBCMC3500IEPP06T6" (150 mm)33.21" (844 mm)---MC3500IEPP06B---0.66" (17 mm)MC3500IEPP08T8" (200 mm)31.16" (791 mm)---MC3500IEPP08B---0.81" (21 mm)MC3500IEPP10T10" (250 mm)29.04" (738 mm)---MC3500IEPP10B---0.93" (24 mm)MC3500IEPP12T12" (300 mm)26.36" (670 mm)---MC3500IEPP12B---1.35" (34 mm)MC3500IEPP15T15" (375 mm)23.39" (594 mm)---MC3500IEPP15B---1.50" (38 mm)MC3500IEPP18TC18" (450 mm)20.03" (509 mm)---MC3500IEPP18TWMC3500IEPP18BC---1.77" (45 mm)MC3500IEPP18BWMC3500IEPP24TC24" (600 mm)14.48" (368 mm)---MC3500IEPP24TWMC3500IEPP24BC---2.06" (52 mm)MC3500IEPP24BWMC3500IEPP30BC30" (750 mm)---2.75" (70 mm)NOMINAL CHAMBER SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)77.0" X 45.0" X 86.0" (1956 mm X 1143 mm X 2184 mm)CHAMBER STORAGE109.9 CUBIC FEET (3.11 m³)MINIMUM INSTALLED STORAGE*175.0 CUBIC FEET (4.96 m³)WEIGHT134 lbs.(60.8 kg)NOMINAL END CAP SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)75.0" X 45.0" X 22.2" (1905 mm X 1143 mm X 564 mm)END CAP STORAGE14.9 CUBIC FEET (0.42 m³)MINIMUM INSTALLED STORAGE*45.1 CUBIC FEET (1.28 m³)WEIGHT49 lbs.(22.2 kg)*ASSUMES 12" (305 mm) STONE ABOVE, 9" (229 mm) STONE FOUNDATION, 6" SPACING BETWEENCHAMBERS, 6" (152 mm) STONE PERIMETER IN FRONT OF END CAPS AND 40% STONE POROSITYMC-3500 TECHNICAL SPECIFICATIONNTS90.0" (2286 mm)ACTUAL LENGTH86.0" (2184 mm)INSTALLEDBUILD ROW IN THIS DIRECTIONNOTE: ALL DIMENSIONS ARE NOMINALLOWER JOINTCORRUGATIONWEBCRESTCRESTSTIFFENING RIBVALLEYSTIFFENING RIBBC75.0"(1905 mm)45.0"(1143 mm)25.7"(653 mm)FOOT77.0"(1956 mm)45.0"(1143 mm)STUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"END CAPS WITH A WELDED CROWN PLATE END WITH "C"END CAPS WITH A PREFABRICATED WELDED STUB END WITH "W"UPPER JOINT CORRUGATION22.2"(564 mm)INSTALLEDCUSTOM PRECORED INVERTS AREAVAILABLE UPON REQUEST.INVENTORIED MANIFOLDS INCLUDE12-24" (300-600 mm) SIZE ON SIZEAND 15-48" (375-1200 mm)ECCENTRIC MANIFOLDS. CUSTOMINVERT LOCATIONS ON THE MC-3500END CAP CUT IN THE FIELD ARE NOTRECOMMENDED FOR PIPE SIZESGREATER THAN 10" (250 mm). THEINVERT LOCATION IN COLUMN 'B'ARE THE HIGHEST POSSIBLE FORTHE PIPE SIZE.PART #STUBBCMC3500IEPP06T6" (150 mm)33.21" (844 mm)---MC3500IEPP06B---0.66" (17 mm)MC3500IEPP08T8" (200 mm)31.16" (791 mm)---MC3500IEPP08B---0.81" (21 mm)MC3500IEPP10T10" (250 mm)29.04" (738 mm)---MC3500IEPP10B---0.93" (24 mm)MC3500IEPP12T12" (300 mm)26.36" (670 mm)---MC3500IEPP12B---1.35" (34 mm)MC3500IEPP15T15" (375 mm)23.39" (594 mm)---MC3500IEPP15B---1.50" (38 mm)MC3500IEPP18TC18" (450 mm)20.03" (509 mm)---MC3500IEPP18TWMC3500IEPP18BC---1.77" (45 mm)MC3500IEPP18BWMC3500IEPP24TC24" (600 mm)14.48" (368 mm)---MC3500IEPP24TWMC3500IEPP24BC---2.06" (52 mm)MC3500IEPP24BWMC3500IEPP30BC30" (750 mm)---2.75" (70 mm)NOMINAL CHAMBER SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)77.0" X 45.0" X 86.0" (1956 mm X 1143 mm X 2184 mm)CHAMBER STORAGE109.9 CUBIC FEET (3.11 m³)MINIMUM INSTALLED STORAGE*175.0 CUBIC FEET (4.96 m³)WEIGHT134 lbs.(60.8 kg)NOMINAL END CAP SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)75.0" X 45.0" X 22.2" (1905 mm X 1143 mm X 564 mm)END CAP STORAGE14.9 CUBIC FEET (0.42 m³)MINIMUM INSTALLED STORAGE*45.1 CUBIC FEET (1.28 m³)WEIGHT49 lbs.(22.2 kg)*ASSUMES 12" (305 mm) STONE ABOVE, 9" (229 mm) STONE FOUNDATION, 6" SPACING BETWEENCHAMBERS, 6" (152 mm) STONE PERIMETER IN FRONT OF END CAPS AND 40% STONE POROSITYMC-3500 TECHNICAL SPECIFICATIONNTS90.0" (2286 mm)ACTUAL LENGTH86.0" (2184 mm)INSTALLEDBUILD ROW IN THIS DIRECTIONNOTE: ALL DIMENSIONS ARE NOMINALLOWER JOINTCORRUGATIONWEBCRESTCRESTSTIFFENING RIBVALLEYSTIFFENING RIBBC75.0"(1905 mm)45.0"(1143 mm)25.7"(653 mm)FOOT77.0"(1956 mm)45.0"(1143 mm)STUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"END CAPS WITH A WELDED CROWN PLATE END WITH "C"END CAPS WITH A PREFABRICATED WELDED STUB END WITH "W"UPPER JOINT CORRUGATION22.2"(564 mm)INSTALLEDCUSTOM PRECORED INVERTS AREAVAILABLE UPON REQUEST.INVENTORIED MANIFOLDS INCLUDE12-24" (300-600 mm) SIZE ON SIZEAND 15-48" (375-1200 mm)ECCENTRIC MANIFOLDS. CUSTOMINVERT LOCATIONS ON THE MC-3500END CAP CUT IN THE FIELD ARE NOTRECOMMENDED FOR PIPE SIZESGREATER THAN 10" (250 mm). THEINVERT LOCATION IN COLUMN 'B'ARE THE HIGHEST POSSIBLE FORTHE PIPE SIZE.4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF56 NYLOPLAST DRAIN BASINNTSNOTES1.8-30" (200-750 mm) GRATES/SOLID COVERS SHALL BE DUCTILE IRON PER ASTM A536GRADE 70-50-052.12-30" (300-750 mm) FRAMES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-053.DRAIN BASIN TO BE CUSTOM MANUFACTURED ACCORDING TO PLAN DETAILS4.DRAINAGE CONNECTION STUB JOINT TIGHTNESS SHALL CONFORM TO ASTM D3212FOR CORRUGATED HDPE (ADS & HANCOR DUAL WALL) & SDR 35 PVC5.FOR COMPLETE DESIGN AND PRODUCT INFORMATION: WWW.NYLOPLAST-US.COM6.TO ORDER CALL: 800-821-6710APART #GRATE/SOLID COVER OPTIONS8"(200 mm)2808AGPEDESTRIAN LIGHTDUTYSTANDARD LIGHTDUTYSOLID LIGHT DUTY10"(250 mm)2810AGPEDESTRIAN LIGHTDUTYSTANDARD LIGHTDUTYSOLID LIGHT DUTY12"(300 mm)2812AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2015"(375 mm)2815AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2018"(450 mm)2818AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2024"(600 mm)2824AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2030"(750 mm)2830AGPEDESTRIANAASHTO H-20STANDARD AASHTOH-20SOLIDAASHTO H-20INTEGRATED DUCTILE IRONFRAME & GRATE/SOLID TOMATCH BASIN O.D.VARIOUS TYPES OF INLET ANDOUTLET ADAPTERS AVAILABLE:4-30" (100-750 mm) FORCORRUGATED HDPEWATERTIGHT JOINT(CORRUGATED HDPE SHOWN)BACKFILL MATERIAL BELOW AND TO SIDESOF STRUCTURE SHALL BE ASTM D2321CLASS I OR II CRUSHED STONE OR GRAVELAND BE PLACED UNIFORMLY IN 12" (305 mm)LIFTS AND COMPACTED TO MIN OF 90%TRAFFIC LOADS: CONCRETE DIMENSIONSARE FOR GUIDELINE PUPOSES ONLY.ACTUAL CONCRETE SLAB MUST BEDESIGNED GIVING CONSIDERATION FORLOCAL SOIL CONDITIONS, TRAFFIC LOADING& OTHER APPLICABLE DESIGN FACTORSADAPTER ANGLES VARIABLE 0°- 360°ACCORDING TO PLANS18" (457 mm)MIN WIDTHAAASHTO H-20 CONCRETE SLAB8" (203 mm) MIN THICKNESSVARIABLE SUMP DEPTHACCORDING TO PLANS[6" (152 mm) MIN ON 8-24" (200-600 mm),10" (254 mm) MIN ON 30" (750 mm)]4" (102 mm) MIN ON 8-24" (200-600 mm)6" (152 mm) MIN ON 30" (750 mm)12" (610 mm) MIN(FOR AASHTO H-20)INVERT ACCORDING TOPLANS/TAKE OFFNyloplast770-932-2443 | WWW.NYLOPLAST-US.COM®4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF66 www.mbakerintl.com APPENDIX G RATIONAL METHOD CALCULATIONS GRATE SIZING CALCULATIONS JENSEN BROOKS 3636 CB GRATE INLET DETAILS SHEET JENSEN BROOKS 2424 CB GRATE INLET DETAILS SHEET Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 08/10/22 File:190260RAT100EXIST3DMA.out ------------------------------------------------------------------------ PROPOSED CARMAX EXPANSION 100-YR DESIGN STORM RATIONAL METHOD CALCULATION BY CARMEN GRACIANO ON 8-10-2022 ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Program License Serial Number 6341 ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 2 Standard intensity-duration curves data (Plate D-4.1) For the [ Cathedral City ] area used. 10 year storm 10 minute intensity = 2.770(In/Hr) 10 year storm 60 minute intensity = 0.980(In/Hr) 100 year storm 10 minute intensity = 4.520(In/Hr) 100 year storm 60 minute intensity = 1.600(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.600(In/Hr) Slope of intensity duration curve = 0.5800 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 10.000 to Point/Station 20.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 358.580(Ft.) Top (of initial area) elevation = 204.000(Ft.) Bottom (of initial area) elevation = 200.280(Ft.) Difference in elevation = 3.720(Ft.) Slope = 0.01037 s(percent)= 1.04 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 7.866 min. Rainfall intensity = 5.199(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.868 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 4.017(CFS) Total initial stream area = 0.890(Ac.) Pervious area fraction = 0.100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 30.000 to Point/Station 40.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 193.980(Ft.) Top (of initial area) elevation = 202.990(Ft.) Bottom (of initial area) elevation = 200.850(Ft.) Difference in elevation = 2.140(Ft.) Slope = 0.01103 s(percent)= 1.10 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 6.077 min. Rainfall intensity = 6.038(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.871 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 0.842(CFS) Total initial stream area = 0.160(Ac.) Pervious area fraction = 0.100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 50.000 to Point/Station 60.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 228.270(Ft.) Top (of initial area) elevation = 203.060(Ft.) Bottom (of initial area) elevation = 200.080(Ft.) Difference in elevation = 2.980(Ft.) Slope = 0.01305 s(percent)= 1.31 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 6.271 min. Rainfall intensity = 5.929(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.871 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 2.633(CFS) Total initial stream area = 0.510(Ac.) Pervious area fraction = 0.100 End of computations, total study area = 1.56 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 0.100 Area averaged RI index number = 32.0 Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 20 - 36X36 - Q=4.017 CFS @ 0.50% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.005 Slope, Sx (ft/ft) = 0.005 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.02 Highlighted Q Total (cfs) = 4.02 Q Capt (cfs) = 4.02 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.78 Efficiency (%) = 100 Gutter Spread (ft) = 95.69 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 20 - 36X36 - Q=4.017 CFS @ 1.79% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.018 Slope, Sx (ft/ft) = 0.018 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.02 Highlighted Q Total (cfs) = 4.02 Q Capt (cfs) = 4.02 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.78 Efficiency (%) = 100 Gutter Spread (ft) = 28.75 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 40 - 24X24 - Q=0.842 CFS @ 1.05% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 2.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.011 Slope, Sx (ft/ft) = 0.011 Local Depr (in) = -0- Gutter Width (ft) = 2.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.84 Highlighted Q Total (cfs) = 0.84 Q Capt (cfs) = 0.84 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.28 Efficiency (%) = 100 Gutter Spread (ft) = 21.46 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 60 -36X36 - Q=2.633 CFS @ 0.60% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.006 Slope, Sx (ft/ft) = 0.006 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.63 Highlighted Q Total (cfs) = 2.63 Q Capt (cfs) = 2.63 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.10 Efficiency (%) = 100 Gutter Spread (ft) = 61.25 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 60 -36X36 - Q=2.633 CFS @ 1.05% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.011 Slope, Sx (ft/ft) = 0.011 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.63 Highlighted Q Total (cfs) = 2.63 Q Capt (cfs) = 2.63 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.10 Efficiency (%) = 100 Gutter Spread (ft) = 34.75 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- ORG. DWG. DATE REV. DWG. DATE BROOKS 3636 CB 36” x 36” CATCH BASIN 11-23-99 02-14-20 7 - 0 6 3636 FRAME ONLY 3636 BOTTOM SECTION ()NO FRAME 3636 E6 3636 E12 12" 6" 1050 525 NONE EXTENSION SECTION HT.LBS KNOCK-OUTS 3636 B36 36"() 30” DIA.4 BOTTOM SECTION HT.LBS KNOCK-OUTS 2,230 41” 6" 6" 44"44" SEE CHART 4" 36” 3636 STEEL COVER - 1 Pc. PARKWAY TRAFFIC 3636 STEEL GRATES - 2 Pc. TRAFFIC 152 lbs. 190 lbs. 3 1/4"35 7/8" 40 1/4" 35 7/8"40 1/4” NOTES: 1.GRATES AND COVERS AVAILABLE PAINTED BLACK OR GALVANIZED 3.BOLT DOWN GRATES AND COVERS ARE AVAILABLE 2.“ADA” OR “HEEL-PROOF” GRATES ARE FOR THIS SERIESNOT AVAILABLE 3636 STEEL GRATES - 1 Pc. PARKWAY 3 1/4" 35 7/8" 40 1/4" NONE 3636 EXTENSION ()NO FRAME 44"44" 36"40 1/2" 4ea. 30” dia. THINWALL KNOCK-OUTS 36"36" 36"36"341 lbs. 93 lbs. ORG. DWG. DATE REV. DWG. DATE 24” x 24” CATCH BASIN 11-23-99 02-14-20 7 - 0 5 2424 TOP SECTION ()WITH GALVANIZED FRAME 48 lbs. 103 lbs. 2424 STEEL COVER PARKWAY TRAFFIC 2424 LOWER SECTION ()NO FRAME 2424 STEEL GRATES PARKWAY TRAFFIC 81 lbs. 114 lbs. 2424 CAST IRON GRATE PARKWAY 112 lbs. 2424 E6 2424 L12 2424 T12 2424 L18 2424 L24 2424 T18 2424 T24 12" 18" 24" 18" 24" 6" 12" 495 745 870 745 870 270 495 () 6” x 11”4 () 9" x 12"4 () 14" x 14"4 () 9" x 12"4 () 14" x 14"4 NONE () 6" x 11"4 EXTENSION SECTION LOWER SECTION HT. HT. LBS LBS KNOCK-OUTS KNOCK-OUTS 2424 B30 2424 B36 36" 30" 1905 1595 () 18" x 18"4 () 18" x 18"4 BOTTOM SECTION HT.LBS KNOCK-OUTS SEE CHART SEE CHART 34"34" SEE CHART 2 1/4" 26" 26" 26 1/4"26 1/4" 24"24" 2424 BOTTOM SECTION ()WITH OR WITHOUT FRAME 24"24" 34"34" BROOKS 2424 CB NOTES: 1.GRATES AND COVERS AVAILABLE PAINTED BLACK OR GALVANIZED 2.PARKWAY & TRAFFIC . 3.“HEEL PROOF” GRATES AVAILABLE IN 4.A TOP SECTION WITH FRAME MUST BE USED IF BOLT DOWN REQUIRED “ADA” GRATES AVAILABLE IN PARKWAY ONLY 2424 T6 6"270 NONE TOP SECTION HT.LBS KNOCK-OUTS 5" 5" 24"24" 4" NOTE:USE 12”, 18”, 24” LOWERS TO INCREASE DEPTH UP TO A MAXIMUM OF 72” 2014 Whitewater River Region WQMP Project Specific Preliminary Water Quality Management Plan For: CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition 73-450 and 73-500 Dinah Shore Drive, Palm Desert, CA 92211 DEVELOPMENT NO. PARCELS “A AND B” OF P.M.W. 17-063 / PARCEL 32-34 OF PM NO. 24255 (PMB 206/94-99) DESIGN REVIEW NO. - Prepared for: Josh Abig CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 Telephone: (804) 747-0422 x 4237 Prepared by: Todd Pitner, PE Danielle Peltier, EIT Michael Baker International 75-410 Gerald Ford Drive, Suite 100 Palm Desert, CA 92211 Telephone: (760) 346-7481 Original Date Prepared: 7/2022 Revision Date(s): - 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition OWNER'S CERTIFICATION This project-specific Water Quality Management Plan (WQMP) has been prepared for: CarMax Auto Superstores, Inc. by Michael Baker International for the project known as CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition at 73-450 and 73-500 Dinah Shore Drive, Palm Desert, CA 92211. This WQMP is intended to comply with the requirements of the City of Palm Desert for the Parcels “A and B” of P.M.W. 17-063 / Parcel 32-34 of PM No. 24255 (PMB 206/94-99), which includes the requirement for the preparation and implementation of a project-specific WQMP. The undersigned, while owning the property/project described in the preceding paragraph, shall be responsible for the implementation of this WQMP and will ensure that this WQMP is amended as appropriate to reflect up-to-date conditions on the site. This WQMP will be reviewed with the facility operator, facility supervisors, employees, tenants, maintenance and service contractors, or any other party (or parties) having responsibility for implementing portions of this WQMP. At least one copy of this WQMP will be maintained at the project site or project office in perpetuity. The undersigned is authorized to certify and to approve implementation of this WQMP. The undersigned is aware that implementation of this WQMP is enforceable under City of Palm Desert Water Quality Ordinance 1247 § 6. If the undersigned transfers its interest in the subject property/project, the undersigned shall notify the successor in interest of its responsibility to implement this WQMP. "I, the undersigned, certify under penalty of law that I am the owner of the property that is the subject of this WQMP, and that the provisions of this WQMP have been reviewed and accepted and that the WQMP will be transferred to future successors in interest." ATTEST Owner's Signature Josh Abig Owner's Printed Name Store Delivery and Support Services Owner's Title/Position Date CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 (804) 747-0422 x 4237 THIS FORM SHALL BE NOTARIZED BEFORE ACCEPTANCE OF THE FINAL PROJECT SPECIFIC WQMP Notary Signature Printed Name Title/Position Date 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-i Contents SECTION PAGE I. Project Description ......................................................................................................................... 1 II. Site Characterization ..................................................................................................................... 6 III. Pollutants of Concern..................................................................................................................... 8 IV. Hydrologic Conditions of Concern .............................................................................................. 9 V. Best Management Practices ........................................................................................................ 11 V.1 SITE DESIGN BMP CONCEPTS, LID/SITE DESIGN AND TREATMENT CONTROL BMPS .... 11 V.1.A SITE DESIGN BMP CONCEPTS AND LID/SITE DESIGN BMPS ................................. 14 V.1.B TREATMENT CONTROL BMPS ................................................................................ 20 V.1.C MEASURABLE GOAL SUMMARY ............................................................................. 22 V.2 SOURCE CONTROL BMPS ................................................................................................. 23 V.3 EQUIVALENT TREATMENT CONTROL BMP ALTERNATIVES ............................................ 26 V.4 REGIONALLY-BASED BMPS ............................................................................................. 26 VI. Operation and Maintenance Responsibility for BMPs .......................................................... 27 VII. Funding .......................................................................................................................................... 29 TABLES TABLE 1. POLLUTANT OF CONCERN SUMMARY 8 TABLE 2. BMP SELECTION MATRIX BASED UPON POLLUTANT OF CONCERN REMOVAL EFFICIENCY 13 TABLE 3. IMPLEMENTATION OF SITE DESIGN BMP CONCEPTS 15 TABLE 4. LID/SITE DESIGN BMPS MEETING THE LID/SITE DESIGN MEASURABLE GOAL 19 TABLE 5: TREATMENT CONTROL BMP SUMMARY 21 TABLE 6: MEASURABLE GOAL SUMMARY 22 TABLE 7. SOURCE CONTROL BMPS 23 APPENDICES A. CONDITIONS OF APPROVAL B. VICINITY MAP, WQMP SITE PLAN, AND RECEIVING WATERS MAP C. SUPPORTING DETAIL RELATED TO HYDROLOGIC CONDITIONS OF CONCERN (IF APPLICABLE) D. EDUCATIONAL MATERIALS E. SOILS REPORT (IF APPLICABLE) F. STRUCTURAL BMP AND/OR RETENTION FACILITY SIZING CALCULATIONS AND DESIGN DETAILS G. AGREEMENTS – CC&RS, COVENANT AND AGREEMENTS, BMP MAINTENANCE AGREEMENTS AND/OR OTHER MECHANISMS FOR ENSURING ONGOING OPERATION, MAINTENANCE, FUNDING AND TRANSFER OF REQUIREMENTS FOR THIS PROJECT-SPECIFIC WQMP H. PHASE 1 ENVIRONMENTAL SITE ASSESSMENT – SUMMARY OF SITE REMEDIATION CONDUCTED AND USE RESTRICTIONS I. PROJECT-SPECIFIC WQMP SUMMARY DATA FORM 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-1 I. Project Description Project Owner: CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 (804) 747-0422 x 4237 WQMP Preparer: Michael Baker International 75-410 Gerald Ford Drive, Suite 100 Palm Desert, CA 92211 (760) 346-7481 Project Site Address: 73-450 and 73-500 Dinah Shore Drive Palm Desert, CA 92211 Planning Area/ Assessment District 2004-02/ Community Name/ City of Palm Desert/ Development Name: CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition APN Number(s): 694-060-034 694-060-036 Latitude & Longitude: 33.8014, -116.3831 Receiving Water: Whitewater River, Coachella Valley Stormwater Channel, Salton Sea Project Site Size: 2.17 acres Standard Industrial Classification (SIC) Code: 5521 Formation of Home Owners' Association (HOA) or Property Owners Association (POA): Y N 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-2 Additional Permits/Approvals required for the Project: AGENCY Permit required State Department of Fish and Wildlife, Fish and Game Code §1602 Streambed Alteration Agreement Y N State Water Resources Control Board, Clean Water Act (CWA) Section 401 Water Quality Certification Y N US Army Corps of Engineers, CWA Section 404 permit Y N US Fish and Wildlife, Endangered Species Act Section 7 biological opinion Y N Statewide Construction General Permit Coverage Y N Statewide Industrial General Permit Coverage Y N Other (please list in the space below as required) City of Palm Desert Building Permit Y N City of Palm Desert Grading Permit Y N • The commercial project will not divert or obstruct the natural flow or change the bed, channel, or bank of any stream, river, or lake. Therefore, a State Department of Fish and Game, 1601 Streambed Alteration Agreement is not required. • The commercial project will not result in discharge into navigable waters; therefore, a Clean Water Act Section 401 Water Quality Certification permit is not required. • The commercial project will not result in the discharge of dredged or fill materials into the waters of the United States, including wetlands. A Clean Water Act Section 404 Permit is not required for this project. • The commercial project site is not recognized as a habitat of an endangered species, nor does it form part of a Conservation Area under the Coachella Valley Multiple Species Habitat Conservation Plan. A U.S. Fish and Wildlife, Endangered Species Act Section 7 biological opinion is not required for this project. • The commercial project is not industrial in nature. Therefore, coverage under the General Permit for Storm Water Discharges Associated with Industrial Activities is not required. This project will obtain coverage under the State Water Board NPDES General Permit for Storm Water Discharges Associated with Construction and Land Disturbance Activities. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-3 Existing Conditions: The 2.17-acre proposed project is located on a vacant, undeveloped lot northwest of the existing store parking lot. The CarMax property consists of two parcels, “Parcels A and B” of Certificate of Compliance, PMW 17-063; the two portions will be referred to as “Parcel A” and “Parcel B”, which can be seen below in Figure 1. The existing store and its associated parking lots are located on Parcel A. This existing development utilizes an aboveground infiltration basin located at the eastern corner of the property. Overflow from the basin is directed to the adjacent Mid-Valley Channel that leads to a regional retention basin. The project site is part of a Regional Hydrology Study for Assessment District No. 2004-02, in which the City of Palm Desert proposed a retention basin for the incremental increase in runoff, due to development, for the 100-year, 24-hour storm. This will be discussed further in following sections of this WQMP report. The landscaped areas on the south and southwest perimeters discharge runoff onto Dinah Shore Drive, joining public drainage facilities that ultimately flow into the regional retention basin. The runoff from the remaining landscape flows into the private onsite retention basin. There is no stormwater run-on from neighboring developments or vacant land. Parcel B mainly consists of a vacant lot with poor land cover. A small section of the parcel is paved with an access driveway. The runoff from the undeveloped land sheet flows from the high point of the parcel located at the northwest corner, outwards towards the perimeter. Runoff from the western corner and southwest edge flows onto Dinah Shore Drive. The remaining runoff flows onto land owned by the City of Palm Desert. This runoff makes its way to the Mid-Valley Channel and ultimately to the regional retention basin. The hydrology and flow patterns of the pre-developed condition can be found in the Hydrology and Hydraulics Report in Appendix F. Proposed Conditions: The proposed development will include a 2,351-sf expansion of the existing CarMax Superstore building, the construction of a 923-sf carwash, and extension of the parking lot on the northwest end of Parcel A onto Parcel B. Demolition of the access driveway will make way for construction of an asphalt sales area on Parcel B. The changes occurring on Parcel A will integrate with the current flow patterns; sheet flow into gutters that lead to the private aboveground retention basin. PARCEL B PARCEL A Figure 1. Parcel Distinction 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-4 The proposed developments on Parcel A will replace impervious asphalt with impervious building, resulting in negligible changes in runoff volumes. The new sales area on Parcel B will utilize an on-site underground retention basin, located at the northeast corner of the project site, that is proposed to contain the pre-developed condition 100-year 24-hour storm. The project site is part of a Regional Hydrology Study for Assessment District No. 2004-02, in which the City of Palm Desert proposed a retention basin for the incremental increase in runoff, due to development, for the 100-year, 24-hour storm. The proximity of the regional basin to the proposed project site can be seen below in Figure 2. By containing the pre-developed condition stormwater volumes on-site, and the difference between the pre-developed and developed condition being contained by the existing regional retention basin, the local ordinance requirement is met. All calculations for the required storage and underground basin size are included within this WQMP Report in Appendix F. If the proposed underground retention basin is filled to capacity, an overflow outlet is proposed to allow stormwater into the City owned, operated, maintained and improved Mid-Valley Channel located northeast of, and adjacent to, the proposed site. Landscaped areas will also be added as part of the proposed development. The outer perimeter of the site will be landscaped with runoff minimizing plant materials and designed to incorporate Coachella Valley Water District standards for the installation of drought tolerant plants to reduce the amount of erosion caused by overwatering, broken irrigation lines, etc. The carwash addition and underground retention chambers will require proper site design and source control measures. The carwash goes through a separate approval process that ensures proper BMP measures are taken. There are no other specific areas where heightened activities would warrant additional site design, source control, or treatment measures. The proposed project does not include any outdoor material storage. The project is expected to generate waste typical of commercial land uses, generally non- hazardous waste. Burrtec Waste Industries will collect the property’s waste on a typical schedule – pollution prevention, recycling practices, and waste reduction will be implemented on-site. Anticipated and potential pollutants generated by land use for parking lots with native landscaping are: Bacteria & Viruses (also: Pathogens), Sediment/Turbidity, Trash & Debris, Heavy Metals, Toxic Organic Compounds (specifically petroleum hydrocarbons), Oil & Grease. The harmful effects of these pollutants shall be reduced through action of the facility operator and proper implementation of BMPs. Upon completion and acceptance of all construction work, the developer, CarMax, will be responsible for operating and maintaining post-construction control measures. Appendix A of the Final project-specific WQMP will include a complete copy of the final Conditions of Approval. Appendix B of this project-specific WQMP includes: Figure 2. Regional Retention Basin in Relation to Project site. MID-VALLEY CHANNEL REGIONAL RETENTION BASIN PROJECT SITE 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-5 a. A Vicinity Map identifying the project site and surrounding planning areas in sufficient detail; and b. A Site Plan for the project. The Site Plan included as part of Appendix B depicts the following project features: ◼ Location and identification of all structural BMPs, including Source Control, LID/Site Design and Treatment Control BMPs. ◼ Landscaped areas. ◼ Paved areas and intended uses (i.e., parking, outdoor work area, outdoor material storage area, sidewalks, patios, tennis courts, etc.). ◼ Number and type of structures and intended uses (i.e., buildings, tenant spaces, dwelling units, community facilities such as pools, recreation facilities, tot lots, etc.). ◼ Infrastructure (i.e., streets, storm drains, etc.) that will revert to public agency ownership and operation. ◼ Location of existing and proposed public and private storm drainage facilities (i.e., storm drains, channels, basins, etc.), including catch basins and other inlets/outlet structures. Existing and proposed drainage facilities should be clearly differentiated. ◼ Location(s) of Receiving Waters to which the project directly or indirectly discharges. ◼ Location of points where onsite (or tributary offsite) flows exit the property/project site. ◼ Delineation of proposed drainage area boundaries, including tributary offsite areas, for each location where flows exit the project site and existing site (where existing site flows are required to be addressed). Each tributary area should be clearly denoted. ◼ Pre- and post-project topography. Appendix I is a one-page form that summarizes pertinent information relative to this project- specific WQMP. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-6 II. Site Characterization Land Use Designation or Zoning: Service Industry Current Property Use: Used-Car Sales Store/Parking Lot/Sales Staging Area Undeveloped/Paved Exit Road Proposed Property Use: Used-Car Sales Store/Parking Lot/Sales Staging Area/Private Carwash Sales Staging Area/Parking Lot Availability of Soils Report: Y N Note: A soils report is required if infiltration BMPs are utilized. Attach report in Appendix E. Phase 1 Site Assessment: Y N Note: If prepared, attached remediation summary and use restrictions in Appendix H. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-7 Receiving Waters for Urban Runoff from Site Receiving Waters EPA Approved 303(d) List Impairments Designated Beneficial Uses Proximity to RARE Beneficial Use Designated Receiving Waters Whitewater River Whitewater River is not a 303(d) impaired waterbody. MUN, AGR, GWR, REC I, REC II, COLD, WILD, POW - Coachella Valley Stormwater Channel* Ammonia, DDT (Dichlorodiphenyltrichloroethane), Dieldrin, Disulfoton, Indicator Bacteria (Pathogens), Dissolved Oxygen, PCBs (Polychlorinated biphenyls), Toxaphene, Toxicity FRSH, REC I**, RECII**, WARM, WILD, RARE*** 4.43 mi Salton Sea Ammonia, Arsenic, Chloride, Chlorpyrifos, DDE (Dichlorodiphenyldichloroethylene), DDT (Dichlorodiphenyltrichloroethane), Enterococcus, Low Dissolved Oxygen, Nutrients, Salinity, Toxicity AQUA, REC I, RECII, WARM, WILD, RARE 27.8 mi *Section of perennial flow from approximately Indio to the Salton Sea. **Unauthorized use. ***Rare, endangered, or threatened wildlife exists in or utilizes some of these waterway(s). If the RARE beneficial use may be affected by a water quality control decision, responsibility for substantiation of the existence of rare, endangered, or threatened species on a case-by-case basis is upon the California Department of Fish and Wildlife on its own initiative and/or at the request of the Regional Water Board; and such substantiation must be provided within a reasonable time frame as approved by the Regional Water Board. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-8 III. Pollutants of Concern Table 1. Pollutant of Concern Summary Pollutant Category Potential for Project and/or Existing Site Causing Receiving Water Impairment Bacteria/Virus Y Y (Indicator Bacteria/Pathogens) Heavy Metals Y Y (Arsenic) Nutrients N Y Toxic Organic Compounds Y Y (DDT, Dieldrin, Disulfoton, PCBs, Toxaphene, Chlorpyrifos, DDE) Sediment/Turbidity Y N Trash & Debris Y N Oil & Grease Y N According to the most recent Colorado River Basin Integrated Report (Category 5 2018 located here: https://www.waterboards.ca.gov/coloradoriver/water_issues/programs/tmdl/rb7_303d_list.html) the Coachella Valley Stormwater Channel is impaired by Ammonia, DDT (Dichlorodiphenyltrichloroethane), Dieldrin, Disulfoton, Indicator Bacteria, Dissolved Oxygen, PCBs (Polychlorinated biphenyls), Toxaphene, and Toxicity, and the Salton Sea is impaired by Ammonia, Arsenic, Chloride, Chlorpyrifos, DDE (Dichlorodiphenyldichloroethylene), DDT (Dichlorodiphenyltrichloroethane), Enterococcus, Low Dissolved Oxygen, Nutrients, Salinity, and Toxicity. NOTE: DDT, DDE, DIELDRIN, PCBs, AND TOXAPHENE ARE BANNED SUBSTANCES IN THE UNITED STATES. DISULFOTON IS A CANCELED PESTICIDE THAT IS NO LONGER PRODUCED IN THE UNITED STATES. Pollutants of Concern: Based on the comparison between the potential project pollutants and the pollutants causing receiving water impairments, the pollutants of concern are in the categories of bacteria/virus, heavy metals, and toxic organic compounds. The project’s existing and proposed storm drain improvements are designed to intercept and retain the flood volume caused by the 100 - year storm event. Therefore, this project will not produce runoff or pollutants that could affect off- site areas or downstream resources, such as the local receiving waters. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-9 IV. Hydrologic Conditions of Concern Local Jurisdiction Requires On-Site Retention of Urban Runoff: Yes The project will be required to retain urban runoff onsite in conformance with local ordinance (See Table 6 of the WQMP Guidance document, "Local Land use Authorities Requiring Onsite Retention of Stormwater"). This section does not need to be completed; however, retention facility design details and sizing calculations must be included in Appendix F. This project is located within Assessment District No. 2004-02 (AD 04-02). As part of the overall design of AD 04-02, an extensive hydrology study and drainage report was prepared and approved by the City of Palm Desert. The proposed project site has been graded as part of the Parcel Map No. 24255 development and drains northeast to the existing Mid-Valley Channel that leads to the master project retention basin, both of which are owned, operated, maintained, and improved by the City of Palm Desert. The basin for AD 04-02 addresses the incremental increase due to development of the 100-year storm event, therefore this project will retain 100% of the 100-year “pre-developed” condition on-site to thereby satisfy the local ordinance requirement for 100% on- site retention for the 100-year, 24-hour storm event. Aerial images of the regional basin are attached within Appendix B of this report. No This section must be completed. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-10 This Project meets the following condition: Condition A: 1) Runoff from the Project is discharged directly to a publicly-owned, operated and maintained MS4 or engineered and maintained channel, 2) the discharge is in full compliance with local land use authority requirements for connections and discharges to the MS4 (including both quality and quantity requirements), 3) the discharge would not significantly impact stream habitat in proximate Receiving Waters, and 4) the discharge is authorized by the local land use authority. (See comments below) Condition B: The project disturbs less than 1 acre and is not part of a larger common plan of development that exceeds 1 acre of disturbance. The disturbed area calculation must include all disturbances associated with larger plans of development. Condition C: The project's runoff flow rate, volume, velocity and duration for the post-development condition do not exceed the pre-development condition for the 2- year, 24-hour and 10-year 24-hour rainfall events. This condition can be achieved by, where applicable, complying with the local land use authority's on-site retention ordinance, or minimizing impervious area on a site and incorporating other Site- Design BMP concepts and LID/Site Design BMPs that assure non-exceedance of pre-development conditions. This condition must be substantiated by hydrologic modeling methods acceptable to the local land use authority. None: Refer to Section 3.4 of the Whitewater River Region WQMP Guidance document for additional requirements. Supporting engineering studies, calculations, and reports are included in Appendix C. 2 year – 24 hour 10 year – 24 hour Precondition Post-condition Precondition Post-condition Discharge (cfs) Velocity (fps) Volume (cubic feet) Duration (minutes) 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-11 V. Best Management Practices This project implements Best Management Practices (BMPs) to address the Pollutants of Concern that may potentially be generated from the use of the project site. These BMPs have been selected and implemented to comply with Section 3.5 of the WQMP Guidance document, and consist of Site Design BMP concepts, Source Control, LID/Site Design and, if/where necessary, Treatment Control BMPs as described herein. V.1 SITE DESIGN BMP CONCEPTS, LID/SITE DESIGN AND TREATMENT CONTROL BMPS Local Jurisdiction Requires On-Site Retention of Urban Runoff: Yes The project will be required to retain Urban Runoff onsite in conformance with local ordinance (See Table 6 of the WQMP Guidance document, "Local Land use Authorities Requiring Onsite Retention of Stormwater). The LID/Site Design measurable goal has thus been met (100%), and Sections V.1.A and V.1.B do not need to be completed; however, retention facility design details and sizing calculations must be included in Appendix F, and '100%' should be entered into Column 3 of Table 6 below. This project is located within Assessment District No. 2004-02 (AD 04-02). As part of the overall design of AD 04-02, an extensive hydrology study and drainage report was prepared and approved by the City of Palm Desert. The proposed project site has been graded as part of the Parcel Map No. 24255 development and drains northeast to the existing Mid-Valley Channel that leads to the master project retention basin, both of which are owned, operated, maintained, and improved by the City of Palm Desert. The basin for AD 04-02 addresses the incremental increase due to development of the 100-year storm event, therefore this project will retain 100% of the 100-year “pre-developed” condition on-site to thereby satisfy the local ordinance requirement for 100% on- site retention for the 100-year, 24-hour storm event. Aerial images of the regional basin are attached within Appendix B of this report. No Section V.1 must be completed. This section of the Project-Specific WQMP documents the LID/Site Design BMPs and, if/where necessary, the Treatment Control BMPs that will be implemented on the project to meet the requirements detailed within Section 3.5.1 of the WQMP Guidance document. Section 3.5.1 includes requirements to implement Site Design Concepts and BMPs, and includes requirements to address Pollutants of Concern with BMPs. Further, sub-section 3.5.1.1 specifically requires that Pollutants of Concern be addressed with LID/Site Design BMPs to the extent feasible. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-12 LID/Site Design BMPs are those BMPs listed within Table 2 below which promote retention and/or feature a natural treatment mechanism; off-site and regionally based BMPs are also LID/Site Design BMPs, and therefore count towards the measurable goal, if they fit these criteria. This project incorporates LID/Site Design BMPs to fully address the Treatment Control BMP requirement where and to the extent feasible. If and where it has been acceptably demonstrated to the local land use authority that it is infeasible to fully meet this requirement with LID/Site Design BMPs, Section V.1.B (below) includes a description of the conventional Treatment Control BMPs that will be substituted to meet the same requirements. In addressing Pollutants of Concern, BMPs are selected using Table 2 below. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-13 Table 2. BMP Selection Matrix Based Upon Pollutant of Concern Removal Efficiency (1) (Sources: Riverside County Flood Control & Water Conservation District Design Handbook for Low Impact Development Best Management Practices, dated September 2011, the Orange County Technical Guidance Document for Water Quality Management Plans, dated May 19, 2011, and the Caltrans Treatment BMP Technology Report, dated April 2010 and April 2008) Pollutant of Concern Landscape Swale2, 3 Landscape Strip2, 3 Biofiltration (with underdrain)2, 3 Extended Detention Basin2 Sand Filter Basin2 Infiltration Basin2 Infiltration Trench2 Permeable Pavement2 Bioretention (w/o underdrain)2, 3 Other BMPs Including Proprietary BMPs4, 6 Sediment & Turbidity M M H M H H H H H Varies by Product5 Nutrients L/M L/M M L/M L/M H H H H Toxic Organic Compounds M/H M/H M/H L L/M H H H H Trash & Debris L L H H H H H L H Bacteria & Viruses (also: Pathogens) L M H L M H H H H Oil & Grease M M H M H H H H H Heavy Metals M M/H M/H L/M M H H H H Abbreviations: L: Low removal efficiency M: Medium removal efficiency H: High removal efficiency Notes: (1) Periodic performance assessment and updating of the guidance provided by this table may be necessary. (2) Expected performance when designed in accordance with the most current edition of the document, "Riverside County, Whitewater River Region Stormwater Quality Best Management Practice Design Handbook". (3) Performance dependent upon design which includes implementation of thick vegetative cover. Local water conservation and/or landscaping requirements should be considered; approval is based on the discretion of the local land use authority. (4) Includes proprietary stormwater treatment devices as listed in the CASQA Stormwater Best Management Practices Handbooks, other stormwater treatment BMPs not specifically listed in this WQMP (including proprietary filters, hydrodynamic separators, inserts, etc.), or newly developed/emerging stormwater treatment technologies. (5) Expected performance should be based on evaluation of unit processes provided by BMP and available testing data. Approval is based on the discretion of the local land use authority. (6) When used for primary treatment as opposed to pre-treatment, requires site-specific approval by the local land use authority. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-14 V.1.A SITE DESIGN BMP CONCEPTS AND LID/SITE DESIGN BMPS This section is not applicable due to conformance with local retention ordinance per Section 3.5.1.2 of the Whitewater River Region WQMP Guidance Document. This section documents the Site Design BMP concepts and LID/Site Design BMPs that will be implemented on this project to comply with the requirements detailed in Section 3.5.1 of the WQMP Guidance document. • Table 3 herein documents the implementation of the Site Design BMP Concepts described in sub-sections 3.5.1.3 and 3.5.1.4. • Table 4 herein documents the extent to which this project has implemented the LID/Site Design goals described in sub-section 3.5.1.1. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-15 Table 3. Implementation of Site Design BMP Concepts This section is not applicable due to conformance with the local retention ordinance. Included Brief Reason for BMPs Indicated as No or N/A Design Concept Technique Specific BMP Yes No N/A Site Design BMP Concept 1 Minimize Urban Runoff, Minimize Impervious Footprint, and Conserve Natural Areas (See WQMP Section 3.5.1.3) Conserve natural areas by concentrating or clustering development on the least environmentally sensitive portions of a site while leaving the remaining land in a natural, undisturbed condition. Conserve natural areas by incorporating the goals of the Multi- Species Habitat Conservation Plan or other natural resource plans. Preserve natural drainage features and natural depressional storage areas on the site. Maximize canopy interception and water conservation by preserving existing native trees and shrubs, and planting additional native or drought tolerant trees and large shrubs. Use natural drainage systems. Where applicable, incorporate Self-Treating Areas Where applicable, incorporate Self-Retaining Areas Increase the building floor to area ratio (i.e., number of stories above or below ground). Construct streets, sidewalks and parking lot aisles to minimum widths necessary, provided that public safety and a walkable environment for pedestrians are not compromised. Reduce widths of streets where off-street parking is available. Minimize the use of impervious surfaces, such as decorative concrete, in the landscape design. Other comparable and equally effective Site Design BMP concept(s) as approved by the local land use authority (Note: Additional narrative required to describe BMP and how it addresses site design concept). 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-16 Table 3. Site Design BMP Concepts (continued) This section is not applicable due to conformance with the local retention ordinance. Included Brief Reason for Each BMP Indicated as No or N/A Design Concept Technique Specific BMP Yes No N/A Site Design BMP Concept 2 Minimize Directly Connected Impervious Area (See WQMP Section 3.5.1.4) Design residential and commercial sites to contain and infiltrate roof runoff, or direct roof runoff to landscaped swales or buffer areas. Drain impervious sidewalks, walkways, trails, and patios into adjacent landscaping. Incorporate landscaped buffer areas between sidewalks and streets. Use natural or landscaped drainage swales in lieu of underground piping or imperviously lined swales. Where soil conditions are suitable, use perforated pipe or gravel filtration pits for low flow infiltration. Maximize the permeable area by constructing walkways, trails, patios, overflow parking, alleys, driveways, low-traffic streets, and other low- traffic areas with open-jointed paving materials or permeable surfaces such as pervious concrete, porous asphalt, unit pavers, and granular materials. Use one or more of the following: Rural swale system: street sheet flows to landscaped swale or gravel shoulder, curbs used at street corners, and culverts used under driveways and street crossings. Urban curb/swale system: street slopes to curb; period ic swale inlets drain to landscaped swale or biofilter. Dual drainage system: first flush captured in street catch basins and discharged to adjacent vegetated swale or gravel shoulder; high flows connect directly to MS4s. Other comparable and equally effective Site Design BMP concept(s) as approved by the local land use authority (Note: Additional narrative required to describe BMP and how it addresses site design concept). Use one or more of the following for design of driveways and private residential parking areas: Design driveways with shared access, flared (single lane at street), or wheel strips (paving only under the tires). Uncovered temporary or guest parking on residential lots paved with a permeable surface, or designed to drain into landscaping. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-17 Table 3. Site Design BMP Concepts (continued) This section is not applicable due to conformance with the local retention ordinance. Included Brief Reason for Each BMP Indicated as No or N/A Design Concept Technique Specific BMP Yes No N/A Site Design BMP Concept 2 (cont'd) Minimize Directly Connected Impervious Area (See WQMP Section 3.5.1.4) Other comparable and equally effective Site Design BMP concept(s) as approved by the local land use authority (Note: Additional narrative required to describe BMP and how it addresses site design concept). Use one or more of the following for design of parking areas: Where landscaping is proposed in parking areas, incorporate parking area landscaping into the drainage design. Overflow parking (parking stalls provided in excess of the Permittee's minimum parking requirements) may be constructed with permeable pavement. Other comparable and equally effective Site Design BMP (or BMPs) as approved by the local land use authority (Note: Additional narrative required describing BMP and how it addresses site design concept). 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-18 Project Site Design BMP Concepts: This project is located within Assessment District No. 2004-02 (AD 04-02). As part of the overall design of AD 04-02, an extensive hydrology study and drainage report was prepared and approved by the City of Palm Desert. The proposed project site has been graded as part of the Parcel Map No. 24255 development and drains northeast to the existing Mid-Valley Channel that leads to the master project retention basin, both of which are owned, operated, maintained, and improved by the City of Palm Desert. The basin for AD 04-02 addresses the incremental increase due to development of the 100-year storm event, therefore this project will retain 100% of the 100-year “pre-developed” condition on-site to thereby satisfy the local ordinance requirement for 100% on- site retention for the 100-year, 24-hour storm event. Aerial images of the regional basin are attached within Appendix B of this report. The proposed on-site underground retention basin, located at the northern corner of the property, is to contain 100% of the “pre-developed” condition controlled by the 100-year, 24-hour storm design from the Riverside County Flood Control and Water Conservation District Hydrology Manual dated April 1978. All calculations for the required storage and basin size are included within this WQMP Report in Appendix F. Alternative Project Site Design BMP Concepts: The proposed project will include Self-Treating Areas (STAs). A STA is an area within a project site that does not drain to a BMP but drains directly offsite or to the MS4 rather than have its runoff comingle with runoff from the project’s impervious surfaces. Parcel A has existing STAs that drain directly onto Dinah Shore Drive and the existing Mid-Valley Channel. Parcel B will incorporate STAs with the same drainage pattern design as the developed Parcel A. The proposed landscaped areas are nearly 100% pervious and therefore qualify as STAs per the 10% or less condition for the impervious landscape features within the STA. The STAs will not require specialized operation and maintenance procedures and will be maintained with normal landscape maintenance. The STAs were removed from the total tributary area that was used to size the underground retention chamber, however, per the Whitewater Region Stormwater Quality Handbook for Low Impact Development, this project area counts towards the LID/site design measurable goal. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-19 Table 4. LID/Site Design BMPs Meeting the LID/Site Design Measurable Goal (1) (2) (3) (4) (5) (6) (7) DRAINAGE SUB-AREA ID OR NO. LID/SITE DESIGN BMP TYPE* POTENTIAL POLLUTANTS OF CONCERN WITHIN DRAINAGE SUB-AREA POTENTIAL POLLUTANTS WITHIN SUB- AREA CAUSING RECEIVING WATER IMPAIRMENTS EFFECTIVENESS OF LID/SITE DESIGN BMP AT ADDRESSING IDENTIFIED POTENTIAL POLLUTANTS BMP MEETS WHICH DESIGN CRITERIA? TOTAL AREA WITHIN DRAINAGE SUB-AREA (See Table 2) (Refer to Table 1) (Refer to Table 1) (U, L, M, H/M, H; see Table 2) (Identify as VBMP OR QBMP) (Nearest 0.1 acre) A INFILTRATION BASIN BACTERIA/VIRUS, HEAVY METALS, TOXIC ORGANIC COMPOUNDS, SEDIMENT/TURBIDITY, TRASH & DEBRIS, OIL & GREASE BACTERIA/VIRUS, HEAVY METALS, TOXIC ORGANIC COMPOUNDS H VBMP 1.6 STA1 SELF-TREATING AREA N/A N/A N/A VBMP 0.3 STA2 SELF-TREATING AREA N/A N/A N/A VBMP 0.2 B INFILTRATION BASIN BACTERIA/VIRUS, HEAVY METALS, TOXIC ORGANIC COMPOUNDS, SEDIMENT/TURBIDITY, TRASH & DEBRIS, OIL & GREASE BACTERIA/VIRUS, HEAVY METALS, TOXIC ORGANIC COMPOUNDS H VBMP 0.1 TOTAL PROJECT AREA TREATED WITH LID/SITE DESIGN BMPs (NEAREST 0.1 ACRE) 2.2 * LID/Site Design BMPs listed in this table are those that completely address the 'Treatment Control BMP requirement' for their drainage sub-area. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-20 Justification of infeasibility for sub-areas not addressed with LID/Site Design BMPs Not applicable. V.1.B TREATMENT CONTROL BMPS Conventional Treatment Control BMPs shall be implemented to address the project's Pollutants of Concern as required in WQMP Section 3.5.1 where, and to the extent that, Section V.1.A has demonstrated that it is infeasible to meet these requirements through implementation of LID/Site Design BMPs. The LID/Site Design BMPs described in Section V.1.A of this project-specific WQMP completely address the 'Treatment Control BMP requirement' for the entire project site (and where applicable, entire existing site) as required in Section 3.5.1.1 of the WQMP Guidance document. Supporting documentation for the sizing of these LID/Site Design BMPs is included in Appendix F. *Section V.1.B does not need to be completed. The LID/Site Design BMPs described in Section V.1.A of this project-specific WQMP do NOT completely address the 'Treatment Control BMP requirement' for the entire project site (or where applicable, entire existing site) as required in Section 3.5.1.1 of the WQMP. *Section V.1.B must be completed. The Treatment Control BMPs identified in this section are selected, sized and implemented to treat the design criteria of VBMP and/or QBMP for all project (and if required, existing site) drainage sub- areas which were not fully addressed using LID/Site Design BMPs. Supporting documentation for the sizing of these Treatment Control BMPs is included in Appendix F. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-21 Table 5: Treatment Control BMP Summary This section is not applicable, the LID/Site Design BMPs described in Section V.1.A of this project-specific WQMP completely address the 'Treatment Control BMP requirement' for the entire project site (and where applicable, entire existing site) as required in Section 3.5.1.1 of the WQMP Guidance document. (1) (2) (3) (4) (5) (6) (7) DRAINAGE SUB-AREA ID OR NO. TREATMENT CONTROL BMP TYPE* POTENTIAL POLLUTANTS OF CONCERN WITHIN DRAINAGE SUB-AREA POTENTIAL POLLUTANTS WITHIN SUB-AREA CAUSING RECEIVING WATER IMPAIRMENTS EFFECTIVENESS OF TREATMENT CONTROL BMP AT ADDRESSING IDENTIFIED POTENTIAL POLLUTANTS BMP MEETS WHICH DESIGN CRITERIA? TOTAL AREA WITHIN DRAINAGE SUB-AREA (See Table 2) (Refer to Table 1) (Refer to Table 1) (U, L, M, H/M, H; see Table 2) (Identify as VBMP OR QBMP) (Nearest 0.1 acre) TOTAL PROJECT AREA TREATED WITH TREATMENT CONTROL BMPs (NEAREST 0.1 ACRE) 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-22 V.1.C MEASURABLE GOAL SUMMARY This section documents the extent to which this project has met the measurable goal described in WQMP Section 3.5.1.1 of addressing 100% of the project's 'Treatment Control BMP requirement' with LID/Site Design BMPs. Projects required to retain Urban Runoff onsite in conformance with local ordinance are considered to have met the measurable goal; for these instances, '100%' is entered into Column 3 of the Table. Table 6: Measurable Goal Summary (1) (2) (3) Total Area Treated with LID/Site Design BMPs Total Area Treated with Treatment Control BMPs % of Treatment Control BMP Requirement addressed with LID/Site Design BMPs (Last row of Table 4) (Last row of Table 5) 2.17 N/A 100% 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-23 V.2 SOURCE CONTROL BMPS This section identifies and describes the Source Control BMPs applicable and implemented on this project. Table 7. Source Control BMPs BMP Name Check One If not applicable, state brief reason Included Not Applicable Non-Structural Source Control BMPs Education for Property Owners, Operators, Tenants, Occupants, or Employees Activity Restrictions Irrigation System and Landscape Maintenance Common Area Litter Control Street Sweeping Private Streets and Parking Lots Drainage Facility Inspection and Maintenance Structural Source Control BMPs Storm Drain Inlet Stenciling and Signage Landscape and Irrigation System Design Protect Slopes and Channels Provide Community Car Wash Racks No public access Properly Design*: Fueling Areas None on-site Air/Water Supply Area Drainage None on-site Trash Storage Areas None on-site Loading Docks None on-site Maintenance Bays None on-site Vehicle and Equipment Wash Areas Outdoor Material Storage Areas None on-site Outdoor Work Areas or Processing Areas None on-site Provide Wash Water Controls for Food Preparation Areas None on-site *Details demonstrating proper design must be included in Appendix F. (Preliminary Grading Plan attached within Appendix F showing properly designed areas.) 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-24 Non-Structural Source Control BMPs: Education for Property Owners and Employees: Practical information materials to promote the prevention of Urban Runoff pollution will be provided by the project proponent to the owner. These materials will include general housekeeping practices that contribute to the protection of urban runoff quality and the BMPs that eliminate or reduce pollution. These materials or a resource list for obtaining these materials will be made available through the local land use authority. BMP training and education programs must be provided to all employees who will be employed or contracted to perform activities that may impact Urban Runoff. Activity Restrictions: Activity Restrictions will be dictated by property owners. Examples of restricted activities include: the blowing, sweeping, or hosing of debris (leaf litter, grass clippings, litter, etc.) into streets, storm drain inlets, or other conveyances is prohibited, and dumpster lids must be closed at all times. Irrigation System and Landscape Maintenance: Maintenance of the irrigation systems and landscaping shall be consistent with the local land use authority’s water conservation ordinance. Fertilizer and pesticide usage shall be consistent with the instructions contained on product labels and with regulations administered by California’s Department of Pesticide Regulation. Landscape maintenance must also address the replacement of dead vegetation, repair of erosion rills, proper disposal of green waste, etc. Irrigation system maintenance must address periodic testing and observation of the irrigation system to detect overspray, broken sprinkler heads, and other system failures. Common Area Litter Control: Trash receptacles must be provided in common areas. Common areas and perimeter fences or walls must be patrolled to collect litter and to notice locations where excessive litter is occurring in order to implement prevention practices such as post public signage, install additional trash receptacles, or increase frequency of emptying trash receptacles. Street Sweeping Private Streets and Parking Lots: The frequency of sweeping privately owned streets shall be no less than the frequency of public street sweeping by the local land use authority. The parking lots shall be swept quarterly, including just prior to the start of the rainy season (November-March in Rancho Mirage). Drainage Facility Inspection and Maintenance: Drainage facilities (catch basins, open channels, and storm drain inlets) shall, at a minimum, take place in the late summer or early fall, prior to the start of the rainy season. The drainage facilities must be cleaned if accumulated sediment/debris fills 25% or more of the sediment/debris storage capacity. Drainage facilities shall be inspected annually, and the cleaning frequency shall be assessed by the responsible party. Structural Source Control BMPs Storm Drain Inlet Stenciling and Signage: Stencils and signs alert the public to the destination of pollutants discharged into Urban Runoff. The responsible party must provide stenciling or labeling of all storm drain inlets and catch basins, constructed or modified, within the project area with prohibitive language (such as: “NO DUMPING ONLY RAIN IN THE DRAIN”) and/or geographical icons to discourage illegal dumping. The legibility of stencils and signs must be maintained by the responsible party. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-25 Landscape and Irrigation System Design: Landscape and irrigation shall be designed to meet the local drought tolerant requirements, reducing overspray, and preventing unnecessary nuisance flows. Protect Slopes and Channels: Project plans include Source Control BMPs to decrease the potential for erosion of slopes and/or channels, consistent with local codes and ordinances, along with the approval of all agencies with jurisdiction. The responsible party must convey runoff safely from the tops of slopes, avoid disturbing steep or unstable slopes and install permanent stabilization BMPs on disturbed slopes as quickly as possible. Native or drought tolerant vegetation shall be planted on slopes on to aid in erosion control. Properly Design Vehicle and Equipment Wash Areas: Discharge of wash waters to the MS4 is prohibited. Therefore, wash areas shall be contained and covered with a roof or overhang and feature adequate surplus storage to prevent excess wash water from entering the MS4. Wash racks shall be connected to the sanitary sewer in accordance with sewering agency guidelines and prior approval. The sewering agency may require discharge monitoring. The equipment wash area drainage system is to capture all wash water; provide impermeable berms, drop inlets, trench catch basins, or overflow containment structures connected to a sump for collection and disposal around wash areas to prevent wash waters from entering MS4. Surface runoff and roof drains shall be directed away from wash area unless approved by sanitary sewering agency. Appendix D includes copies of the educational materials (described in Section 3.5.2.1 of the WQMP Guidance document) that will be used in implementing this project specific WQMP. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-26 V.3 EQUIVALENT TREATMENT CONTROL BMP ALTERNATIVES Not applicable. V.4 REGIONALLY-BASED BMPS This project is located within Assessment District No. 2004-02 (AD 04-02). As part of the overall design of AD 04-02, an extensive hydrology study and drainage report was prepared and approved by the City of Palm Desert. The proposed project site has been graded as part of the Parcel Map No. 24255 development and drains northeast to the existing Mid-Valley Channel that leads to the master project retention basin, both of which are owned, operated, maintained, and improved by the City of Palm Desert. The basin for AD 04-02 addresses the incremental increase due to development of the 100-year storm event, therefore this project will retain 100% of the 100-year “pre-developed” condition on-site to thereby satisfy the local ordinance requirement for 100% on- site retention for the 100-year, 24-hour storm event. Aerial images of the regional basin are attached within Appendix B of this report. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-27 VI. Operation and Maintenance Responsibility for BMPs Appendix G of the Final project-specific WQMP will include copies of CC&Rs, Covenant and Agreements, BMP Maintenance Agreement and/or other mechanisms used to ensure the ongoing operation, maintenance, funding, transfer and implementation of the project-specific WQMP requirements. The following maintenance recommendations, which include the responsible parties, inspection intervals, and maintenance intervals, are not intended to be exhaustive in nature and should not serve as the sole source of on-site operating procedures. Where applicable, refer to the equipment manufacturer’s recommendations, other relevant maintenance recommendations and the Declaration of Covenants, Conditions and Restrictions, Reservation of Easements that apply to this site. The owner will be the responsible party for all operation and maintenance activities, including inspections and record keeping for a minimum of 50 years. The owner may appoint a maintenance company that will execute these responsibilities. All implementation for operation and maintenance will occur post-construction. Irrigation System and Landscape: O and M Activities Schedule and Frequency 1. Inspect and repair broken sprinklers. Inspect weekly and replace immediately 2. Repair broken water lines. Inspect daily and repair immediately. 3. Inspect irrigated areas for signs of erosion and/ or discharge Inspect weekly repair source of erosion or discharge immediately. Common Area Litter Control: O and M Activities Schedule and Frequency 4. Ensure preventative signage maintains legibility and visibility. As needed. 5. Continuously look out for litter and clean up immediately. Continuous inspection while performing duties. 6. Add trash cans where littering is prominent and can be mediated. As needed. Street Sweeping of Private Streets and Parking Lots: O and M Activities Schedule and Frequency 7. Inspect for tracked sediment or blow sand. Visible sediment tracking should be swept immediately. Inspect monthly. Sweeping operations should occur on a basis in conformance with the local land use authority. 8. Adjust brooms frequently; maximize efficiency of sweeping efforts. As needed. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-28 Drainage Facilities: O and M Activities Schedule and Frequency 9. Inspect, repair, and replace any broken or buried drain grates. Inspect weekly and replace immediately. 10. Inspect and remove trash and debris from catch basin inlets and storm drain mains. If sediment or trash exists remove and dispose as directed hereon. Inspect prior to the rainy season (September) and after the rainy season (April). Provide performance inspections subsequent to all rain events. 11. Inspect catch basins and re-apply stenciling and/or signage when necessary. Inspect annually and as needed. Protect Slopes and Channels: O and M Activities Schedule and Frequency 12. Inspect slopes and channels. Remove any litter/debris within channels or swales conveying stormwater runoff. Provide stabilized slopes and outlet structures. As needed. Retention Basin (Infiltration BMP): O and M Activities Schedule and Frequency 13. Inspect all inlets to the Retention area. Make sure inlets are free of debris and sediment. Inspect inlets for sediment accumulation and clean and remove trash when encountered. Inspect prior to the rainy season (September) and after the rainy season (April). Inspect prior and after all rain events. 14. Inspect the underground chamber system isolator row through the inspection port for built up sediment. If sediment is at or above 3 inch depth, clean out Isolator Row Plus using the JetVac process. Inspect prior to the rainy season (September) and after the rainy season (April). Responsible Party: CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 (804) 747-0422 Contact: Josh Abig Note: Sediment, other pollutants, and all other waste shall be properly disposed of in a licensed landfill or by another appropriate disposal method in accordance with local, state, and federal regulations. 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition July 2022 1-29 Funding The property title holder shall carry primary responsibility for the initial funding of installations, design and implementations of site specific BMPs. Ongoing inspections, routine maintenance, and some instances of reactionary maintenance shall be funded by the property owner, in such that he will make an agreement with contractors, tenants, or other parties in direct access and knowledge of the property to pay for any or all aspects of the necessary maintenance and inspections. Continued funding for ongoing inspections and maintenance shall be passed to any, and all, future title holders and awareness must be made of this obligation in conjunction with the title. In addition, any future property owners, managers, tenants, or contractors must be made aware of the site’s structural BMPs and have access to their associated educational materials that are to be kept on the site, within the site’s respective building as well as held by the property owner and title company or others who may possess the title or deed to the property. Any amended versions of the funding declaration may be submitted to all applicable parties in the future, should such an action be warranted. All changes must be submitted for a review by the City of Palm Desert, as per their standards and requirements for altering this document. Appendix G of this project-specific WQMP also includes copies of Covenants and Agreements, BMP Maintenance Agreement and/or other mechanisms used to ensure the ongoing operation, maintenance, funding, transfer and implementation of the project-specific WQMP requirements. Property Owner: CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 Telephone: (804) 747-0422 x 4237 Contact Person: Josh Abig 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix A Conditions of Approval To be provided in Final WQMP Planning Commission Resolution Dated 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix B Vicinity Map WQMP Site Plan Receiving Waters Map Aerial of Regional Retention Basin for Assessment District 2004 -02 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERTOD D L. PITNERNo. C58606"NOT FOR CONSTRUCTION"REVISED: 08/11/2022 Whitewater River Region WQMP Guidance June 2014 10Figure 2. Whitewater River Region Receiving Waters MapPROJECT SITE Parcel Map 24455 RETENTION BASIN FOR MASTER PLANNED SITE 600 ft N➤➤N© 2016 Google © 2016 Google © 2016 Google PROJECT SITE - CARMAX PROJECT RETAINS EXISTING CONDITIONS 100-YR 24-HR EVENT ONSITE AND OVERFLOWS TO LOCAL CHANNEL LOCAL CONCRETE CONVEYANCE CHANNEL FOR PM24255 LOCAL RETENTION BASIN FOR PROJECT PM24255 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix C Supporting Detail Related to Hydrologic Conditions of Concern See Appendix F 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix D Educational Materials SD-10 Site Design and Landscape Planning SD-11 Roof Runoff Controls SD-12 Efficient Irrigation SD-13 Storm Drain System Signs SD-33 Vehicle Washing Areas SC-10 Non-Stormwater Discharges SC-11 Spill Prevention, Control & Cleanup SC-21 Vehicle and Equipment Cleaning SC-34 Waste Handling and Disposal SC-41 Building & Grounds Maintenance SC-43 Parking/Storage Area Maintenance SC-60 Housekeeping Practices SC-61 Safer Alternative Products SC-70 Road and Street Maintenance SC-71 Plaza and Sidewalk Cleaning SC-73 Landscape Maintenance SC-74 Drainage System Maintenance SC-75 Waste Handlin and Disposal SC-76 Water and Sewer Utility Maintenance TC-11 Infiltration Basin Isolator Row Plus O&M Manual Coachella Valley Vector Control Information Site Design & Landscape Planning SD-10 January 2003 California Stormwater BMP Handbook 1 of 4 New Development and Redevelopment www.cabmphandbooks.com Description Each project site possesses unique topographic, hydrologic, and vegetative features, some of which are more suitable for development than others. Integrating and incorporating appropriate landscape planning methodologies into the project design is the most effective action that can be done to minimize surface and groundwater contamination from stormwater. Approach Landscape planning should couple consideration of land suitability for urban uses with consideration of community goals and projected growth. Project plan designs should conserve natural areas to the extent possible, maximize natural water storage and infiltration opportunities, and protect slopes and channels. Suitable Applications Appropriate applications include residential, commercial and industrial areas planned for development or redevelopment. Design Considerations Design requirements for site design and landscapes planning should conform to applicable standards and specifications of agencies with jurisdiction and be consistent with applicable General Plan and Local Area Plan policies. Design Objectives ; Maximize Infiltration ; Provide Retention ; Slow Runoff ; Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey SD-10 Site Design & Landscape Planning 2 of 4 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com Designing New Installations Begin the development of a plan for the landscape unit with attention to the following general principles: „ Formulate the plan on the basis of clearly articulated community goals. Carefully identify conflicts and choices between retaining and protecting desired resources and community growth. „ Map and assess land suitability for urban uses. Include the following landscape features in the assessment: wooded land, open unwooded land, steep slopes, erosion-prone soils, foundation suitability, soil suitability for waste disposal, aquifers, aquifer recharge areas, wetlands, floodplains, surface waters, agricultural lands, and various categories of urban land use. When appropriate, the assessment can highlight outstanding local or regional resources that the community determines should be protected (e.g., a scenic area, recreational area, threatened species habitat, farmland, fish run). Mapping and assessment should recognize not only these resources but also additional areas needed for their sustenance. Project plan designs should conserve natural areas to the extent possible, maximize natural water storage and infiltration opportunities, and protect slopes and channels. Conserve Natural Areas during Landscape Planning If applicable, the following items are required and must be implemented in the site layout during the subdivision design and approval process, consistent with applicable General Plan and Local Area Plan policies: „ Cluster development on least-sensitive portions of a site while leaving the remaining land in a natural undisturbed condition. „ Limit clearing and grading of native vegetation at a site to the minimum amount needed to build lots, allow access, and provide fire protection. „ Maximize trees and other vegetation at each site by planting additional vegetation, clustering tree areas, and promoting the use of native and/or drought tolerant plants. „ Promote natural vegetation by using parking lot islands and other landscaped areas. „ Preserve riparian areas and wetlands. Maximize Natural Water Storage and Infiltration Opportunities Within the Landscape Unit „ Promote the conservation of forest cover. Building on land that is already deforested affects basin hydrology to a lesser extent than converting forested land. Loss of forest cover reduces interception storage, detention in the organic forest floor layer, and water losses by evapotranspiration, resulting in large peak runoff increases and either their negative effects or the expense of countering them with structural solutions. „ Maintain natural storage reservoirs and drainage corridors, including depressions, areas of permeable soils, swales, and intermittent streams. Develop and implement policies and Site Design & Landscape Planning SD-10 January 2003 California Stormwater BMP Handbook 3 of 4 New Development and Redevelopment www.cabmphandbooks.com regulations to discourage the clearing, filling, and channelization of these features. Utilize them in drainage networks in preference to pipes, culverts, and engineered ditches. „ Evaluating infiltration opportunities by referring to the stormwater management manual for the jurisdiction and pay particular attention to the selection criteria for avoiding groundwater contamination, poor soils, and hydrogeological conditions that cause these facilities to fail. If necessary, locate developments with large amounts of impervious surfaces or a potential to produce relatively contaminated runoff away from groundwater recharge areas. Protection of Slopes and Channels during Landscape Design „ Convey runoff safely from the tops of slopes. „ Avoid disturbing steep or unstable slopes. „ Avoid disturbing natural channels. „ Stabilize disturbed slopes as quickly as possible. „ Vegetate slopes with native or drought tolerant vegetation. „ Control and treat flows in landscaping and/or other controls prior to reaching existing natural drainage systems. „ Stabilize temporary and permanent channel crossings as quickly as possible, and ensure that increases in run-off velocity and frequency caused by the project do not erode the channel. „ Install energy dissipaters, such as riprap, at the outlets of new storm drains, culverts, conduits, or channels that enter unlined channels in accordance with applicable specifications to minimize erosion. Energy dissipaters shall be installed in such a way as to minimize impacts to receiving waters. „ Line on-site conveyance channels where appropriate, to reduce erosion caused by increased flow velocity due to increases in tributary impervious area. The first choice for linings should be grass or some other vegetative surface, since these materials not only reduce runoff velocities, but also provide water quality benefits from filtration and infiltration. If velocities in the channel are high enough to erode grass or other vegetative linings, riprap, concrete, soil cement, or geo-grid stabilization are other alternatives. „ Consider other design principles that are comparable and equally effective. Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define “redevelopment” in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. The definition of “ redevelopment” must be consulted to determine whether or not the requirements for new development apply to areas intended for redevelopment. If the definition applies, the steps outlined under “designing new installations” above should be followed. SD-10 Site Design & Landscape Planning 4 of 4 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com Redevelopment may present significant opportunity to add features which had not previously been implemented. Examples include incorporation of depressions, areas of permeable soils, and swales in newly redeveloped areas. While some site constraints may exist due to the status of already existing infrastructure, opportunities should not be missed to maximize infiltration, slow runoff, reduce impervious areas, disconnect directly connected impervious areas. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Stormwater Management Manual for Western Washington, Washington State Department of Ecology, August 2001. Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. Roof Runoff Controls SD-11 January 2003 California Stormwater BMP Handbook 1 of 3 New Development and Redevelopment www.cabmphandbook.com Description Various roof runoff controls are available to address stormwater that drains off rooftops. The objective is to reduce the total volume and rate of runoff from individual lots, and retain the pollutants on site that may be picked up from roofing materials and atmospheric deposition. Roof runoff controls consist of directing the roof runoff away from paved areas and mitigating flow to the storm drain system through one of several general approaches: cisterns or rain barrels; dry wells or infiltration trenches; pop-up emitters, and foundation planting. The first three approaches require the roof runoff to be contained in a gutter and downspout system. Foundation planting provides a vegetated strip under the drip line of the roof. Approach Design of individual lots for single-family homes as well as lots for higher density residential and commercial structures should consider site design provisions for containing and infiltrating roof runoff or directing roof runoff to vegetative swales or buffer areas. Retained water can be reused for watering gardens, lawns, and trees. Benefits to the environment include reduced demand for potable water used for irrigation, improved stormwater quality, increased groundwater recharge, decreased runoff volume and peak flows, and decreased flooding potential. Suitable Applications Appropriate applications include residential, commercial and industrial areas planned for development or redevelopment. Design Considerations Designing New Installations Cisterns or Rain Barrels One method of addressing roof runoff is to direct roof downspouts to cisterns or rain barrels. A cistern is an above ground storage vessel with either a manually operated valve or a permanently open outlet. Roof runoff is temporarily stored and then released for irrigation or infiltration between storms. The number of rain Design Objectives ; Maximize Infiltration ; Provide Retention ; Slow Runoff Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials ; Contain Pollutants Collect and Convey Rain Garden SD-11 Roof Runoff Controls 2 of 3 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbook.com barrels needed is a function of the rooftop area. Some low impact developers recommend that every house have at least 2 rain barrels, with a minimum storage capacity of 1000 liters. Roof barrels serve several purposes including mitigating the first flush from the roof which has a high volume, amount of contaminants, and thermal load. Several types of rain barrels are commercially available. Consideration must be given to selecting rain barrels that are vector proof and childproof. In addition, some barrels are designed with a bypass valve that filters out grit and other contaminants and routes overflow to a soak-away pit or rain garden. If the cistern has an operable valve, the valve can be closed to store stormwater for irrigation or infiltration between storms. This system requires continual monitoring by the resident or grounds crews, but provides greater flexibility in water storage and metering. If a cistern is provided with an operable valve and water is stored inside for long periods, the cistern must be covered to prevent mosquitoes from breeding. A cistern system with a permanently open outlet can also provide for metering stormwater runoff. If the cistern outlet is significantly smaller than the size of the downspout inlet (say ¼ to ½ inch diameter), runoff will build up inside the cistern during storms, and will empty out slowly after peak intensities subside. This is a feasible way to mitigate the peak flow increases caused by rooftop impervious land coverage, especially for the frequent, small storms. Dry wells and Infiltration Trenches Roof downspouts can be directed to dry wells or infiltration trenches. A dry well is constructed by excavating a hole in the ground and filling it with an open graded aggregate, and allowing the water to fill the dry well and infiltrate after the storm event. An underground connection from the downspout conveys water into the dry well, allowing it to be stored in the voids. To minimize sedimentation from lateral soil movement, the sides and top of the stone storage matrix can be wrapped in a permeable filter fabric, though the bottom may remain open. A perforated observation pipe can be inserted vertically into the dry well to allow for inspection and maintenance. In practice, dry wells receiving runoff from single roof downspouts have been successful over long periods because they contain very little sediment. They must be sized according to the amount of rooftop runoff received, but are typically 4 to 5 feet square, and 2 to 3 feet deep, with a minimum of 1-foot soil cover over the top (maximum depth of 10 feet). To protect the foundation, dry wells must be set away from the building at least 10 feet. They must be installed in solids that accommodate infiltration. In poorly drained soils, dry wells have very limited feasibility. Infiltration trenches function in a similar manner and would be particularly effective for larger roof areas. An infiltration trench is a long, narrow, rock-filled trench with no outlet that receives stormwater runoff. These are described under Treatment Controls. Pop-up Drainage Emitter Roof downspouts can be directed to an underground pipe that daylights some distance from the building foundation, releasing the roof runoff through a pop-up emitter. Similar to a pop-up irrigation head, the emitter only opens when there is flow from the roof. The emitter remains flush to the ground during dry periods, for ease of lawn or landscape maintenance. Roof Runoff Controls SD-11 January 2003 California Stormwater BMP Handbook 3 of 3 New Development and Redevelopment www.cabmphandbook.com Foundation Planting Landscape planting can be provided around the base to allow increased opportunities for stormwater infiltration and protect the soil from erosion caused by concentrated sheet flow coming off the roof. Foundation plantings can reduce the physical impact of water on the soil and provide a subsurface matrix of roots that encourage infiltration. These plantings must be sturdy enough to tolerate the heavy runoff sheet flows, and periodic soil saturation. Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define “redevelopment” in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. The definition of “ redevelopment” must be consulted to determine whether or not the requirements for new development apply to areas intended for redevelopment. If the definition applies, the steps outlined under “designing new installations” above should be followed. Supplemental Information Examples „ City of Ottawa’s Water Links Surface –Water Quality Protection Program „ City of Toronto Downspout Disconnection Program „ City of Boston, MA, Rain Barrel Demonstration Program Other Resources Hager, Marty Catherine, Stormwater, “Low-Impact Development”, January/February 2003. www.stormh2o.com Low Impact Urban Design Tools, Low Impact Development Design Center, Beltsville, MD. www.lid-stormwater.net Start at the Source, Bay Area Stormwater Management Agencies Association, 1999 Edition Efficient Irrigation SD-12 January 2003 California Stormwater BMP Handbook 1 of 2 New Development and Redevelopment www.cabmphandbooks.com Description Irrigation water provided to landscaped areas may result in excess irrigation water being conveyed into stormwater drainage systems. Approach Project plan designs for development and redevelopment should include application methods of irrigation water that minimize runoff of excess irrigation water into the stormwater conveyance system. Suitable Applications Appropriate applications include residential, commercial and industrial areas planned for development or redevelopment. (Detached residential single-family homes are typically excluded from this requirement.) Design Considerations Designing New Installations The following methods to reduce excessive irrigation runoff should be considered, and incorporated and implemented where determined applicable and feasible by the Permittee: „ Employ rain-triggered shutoff devices to prevent irrigation after precipitation. „ Design irrigation systems to each landscape area’s specific water requirements. „ Include design featuring flow reducers or shutoff valves triggered by a pressure drop to control water loss in the event of broken sprinkler heads or lines. „ Implement landscape plans consistent with County or City water conservation resolutions, which may include provision of water sensors, programmable irrigation times (for short cycles), etc. Design Objectives ; Maximize Infiltration ; Provide Retention ; Slow Runoff Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey SD-12 Efficient Irrigation 2 of 2 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com „ Design timing and application methods of irrigation water to minimize the runoff of excess irrigation water into the storm water drainage system. „ Group plants with similar water requirements in order to reduce excess irrigation runoff and promote surface filtration. Choose plants with low irrigation requirements (for example, native or drought tolerant species). Consider design features such as: - Using mulches (such as wood chips or bar) in planter areas without ground cover to minimize sediment in runoff - Installing appropriate plant materials for the location, in accordance with amount of sunlight and climate, and use native plant materials where possible and/or as recommended by the landscape architect - Leaving a vegetative barrier along the property boundary and interior watercourses, to act as a pollutant filter, where appropriate and feasible - Choosing plants that minimize or eliminate the use of fertilizer or pesticides to sustain growth „ Employ other comparable, equally effective methods to reduce irrigation water runoff. Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define “redevelopment” in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. The definition of “ redevelopment” must be consulted to determine whether or not the requirements for new development apply to areas intended for redevelopment. If the definition applies, the steps outlined under “designing new installations” above should be followed. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. Storm Drain Signage SD-13 January 2003 California Stormwater BMP Handbook 1 of 2 New Development and Redevelopment www.cabmphandbooks.com Description Waste materials dumped into storm drain inlets can have severe impacts on receiving and ground waters. Posting notices regarding discharge prohibitions at storm drain inlets can prevent waste dumping. Storm drain signs and stencils are highly visible source controls that are typically placed directly adjacent to storm drain inlets. Approach The stencil or affixed sign contains a brief statement that prohibits dumping of improper materials into the urban runoff conveyance system. Storm drain messages have become a popular method of alerting the public about the effects of and the prohibitions against waste disposal. Suitable Applications Stencils and signs alert the public to the destination of pollutants discharged to the storm drain. Signs are appropriate in residential, commercial, and industrial areas, as well as any other area where contributions or dumping to storm drains is likely. Design Considerations Storm drain message markers or placards are recommended at all storm drain inlets within the boundary of a development project. The marker should be placed in clear sight facing toward anyone approaching the inlet from either side. All storm drain inlet locations should be identified on the development site map. Designing New Installations The following methods should be considered for inclusion in the project design and show on project plans: „ Provide stenciling or labeling of all storm drain inlets and catch basins, constructed or modified, within the project area with prohibitive language. Examples include “NO DUMPING Design Objectives Maximize Infiltration Provide Retention Slow Runoff Minimize Impervious Land Coverage ; Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey SD-13 Storm Drain Signage 2 of 2 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com – DRAINS TO OCEAN” and/or other graphical icons to discourage illegal dumping. „ Post signs with prohibitive language and/or graphical icons, which prohibit illegal dumping at public access points along channels and creeks within the project area. Note - Some local agencies have approved specific signage and/or storm drain message placards for use. Consult local agency stormwater staff to determine specific requirements for placard types and methods of application. Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define “redevelopment” in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. If the project meets the definition of “redevelopment”, then the requirements stated under “ designing new installations” above should be included in all project design plans. Additional Information Maintenance Considerations „ Legibility of markers and signs should be maintained. If required by the agency with jurisdiction over the project, the owner/operator or homeowner’s association should enter into a maintenance agreement with the agency or record a deed restriction upon the property title to maintain the legibility of placards or signs. Placement „ Signage on top of curbs tends to weather and fade. „ Signage on face of curbs tends to be worn by contact with vehicle tires and sweeper brooms. Supplemental Information Examples „ Most MS4 programs have storm drain signage programs. Some MS4 programs will provide stencils, or arrange for volunteers to stencil storm drains as part of their outreach program. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. Vehicle Washing Areas SD-33 January 2003 California Stormwater BMP Handbook 1 of 2 New Development and Redevelopment www.cabmphandbooks.com Description Vehicle washing, equipment washing, and steam cleaning may contribute high concentrations of metals, oil and grease, solvents, phosphates, and suspended solids to wash waters that drain to stormwater conveyance systems. Approach Project plans should include appropriately designed area(s) for washing-steam cleaning of vehicles and equipment. Depending on the size and other parameters of the wastewater facility, wash water may be conveyed to a sewer, an infiltration system, recycling system or other alternative. Pretreatment may be required for conveyance to a sanitary sewer. Suitable Applications Appropriate applications include commercial developments, restaurants, retail gasoline outlets, automotive repair shops and others. Design Considerations Design requirements for vehicle maintenance are governed by Building and Fire Codes, and by current local agency ordinances, and zoning requirements. Design criteria described in this fact sheet are meant to enhance and be consistent with these code requirements. Designing New Installations Areas for washing/steam cleaning should incorporate one of the following features: „ Be self-contained and/or covered with a roof or overhang „ Be equipped with a clarifier or other pretreatment facility „ Have a proper connection to a sanitary sewer Design Objectives ; Maximize Infiltration Provide Retention Slow Runoff Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials ; Contain Pollutants ; Collect and Convey Photo Credit: Geoff Brosseau SD-33 Vehicle Washing Areas 2 of 2 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com „ Include other features which are comparable and equally effective CAR WASH AREAS - Some jurisdictions’ stormwater management plans include vehicle- cleaning area source control design requirements for community car wash racks in complexes with a large number of dwelling units. In these cases, wash water from the areas may be directed to the sanitary sewer, to an engineered infiltration system, or to an equally effective alternative. Pre-treatment may also be required. Depending on the jurisdiction, developers may be directed to divert surface water runoff away from the exposed area around the wash pad ( parking lot, storage areas), and wash pad itself to alternatives other than the sanitary sewer. Roofing may be required for exposed wash pads. It is generally advisable to cover areas used for regular washing of vehicles, trucks, or equipment, surround them with a perimeter berm, and clearly mark them as a designated washing area. Sumps or drain lines can be installed to collect wash water, which may be treated for reuse or recycling, or for discharge to the sanitary sewer. Jurisdictions may require some form of pretreatment, such as a trap, for these areas. Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define “redevelopment” in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. The definition of “ redevelopment” must be consulted to determine whether or not the requirements for new development apply to areas intended for redevelopment. Additional Information Maintenance Considerations Stormwater and non-stormwater will accumulate in containment areas and sumps with impervious surfaces. Contaminated accumulated water must be disposed of in accordance with applicable laws and cannot be discharged directly to the storm drain or sanitary sewer system without the appropriate permit. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 1 of 11 Municipal www.cabmphandbooks.com Description Non-stormwater discharges are those flows that do not consist entirely of stormwater. For municipalities non-stormwater discharges present themselves in two situations. One is from fixed facilities owned and/or operated by the municipality. The other situation is non-stormwater discharges that are discovered during the normal operation of a field program. Some non- stormwater discharges do not include pollutants and may be discharged to the storm drain. These include uncontaminated groundwater and natural springs. There are also some non- stormwater discharges that typically do not contain pollutants and may be discharged to the storm drain with conditions. These include car washing, and surface cleaning. However, there are certain non-stormwater discharges that pose environmental concern. These discharges may originate from illegal dumping or from internal floor drains, appliances, industrial processes, sinks, and toilets that are connected to the nearby storm drainage system. These discharges (which may include: process waste waters, cooling waters, wash waters, and sanitary wastewater) can carry substances (such as paint, oil, fuel and other automotive fluids, chemicals and other pollutants) into storm drains. The ultimate goal is to effectively eliminate non- stormwater discharges to the stormwater drainage system through implementation of measures to detect, correct, and enforce against illicit connections and illegal discharges. Approach The municipality must address non-stormwater discharges from its fixed facilities by assessing the types of non-stormwater discharges and implementing BMPs for the discharges determined to pose environmental concern. For field programs Objectives „ Contain „ Educate „ Reduce/Minimize Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; Graphic by: Margie Winter SC-10 Non-Stormwater Discharges 2 of 11 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com the field staff must be trained to now what to look for regarding non-stormwater discharges and the procedures to follow in investigating the detected discharges. Suggested Protocols Fixed Facility General „ Post “No Dumping” signs with a phone number for reporting dumping and disposal. Signs should also indicate fines and penalties for illegal dumping. „ Stencil storm drains, where applicable, to prevent illegal disposal of pollutants. Storm drain inlets should have messages such as “Dump No Waste Drains to Stream” stenciled next to them to warn against ignorant or intentional dumping of pollutants into the storm drainage system. „ Landscaping and beautification efforts of hot spots might also discourage future dumping, as well as provide open space and increase property values. „ Lighting or barriers may also be needed to discourage future dumping. Illicit Connections „ Locate discharges from the fixed facility drainage system to the municipal storm drain system through review of “as-built” piping schematics. „ Use techniques such as smoke testing, dye testing and television camera inspection (as noted below) to verify physical connections. „ Isolate problem areas and plug illicit discharge points. Visual Inspection and Inventory „ Inventory and inspect each discharge point during dry weather. „ Keep in mind that drainage from a storm event can continue for several days following the end of a storm and groundwater may infiltrate the underground stormwater collection system. Also, non-stormwater discharges are often intermittent and may require periodic inspections. Review Infield Piping „ Review the “as-built” piping schematic as a way to determine if there are any connections to the stormwater collection system. „ Inspect the path of floor drains in older buildings. Smoke Testing „ Smoke testing of wastewater and stormwater collection systems is used to detect connections between the two systems. Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 3 of 11 Municipal www.cabmphandbooks.com „ During dry weather the stormwater collection system is filled with smoke and then traced to sources. The appearance of smoke at the base of a toilet indicates that there may be a connection between the sanitary and the stormwater system. Dye Testing „ A dye test can be performed by simply releasing a dye into either your sanitary or process wastewater system and examining the discharge points from the stormwater collection system for discoloration. TV Inspection of Storm Sewer „ TV Cameras can be employed to visually identify illicit connections to the fixed facility storm drain system. Illegal Dumping „ Regularly inspect and clean up hot spots and other storm drainage areas where illegal dumping and disposal occurs. „ Clean up spills on paved surfaces with as little water as possible. Use a rag for small spills, a damp mop for general cleanup, and absorbent material for larger spills. If the spilled material is hazardous, then the used cleanup materials are also hazardous and must be sent to a certified laundry (rags) or disposed of as hazardous waste. „ Never hose down or bury dry material spills. Sweep up the material and dispose of properly. „ Use adsorbent materials on small spills rather than hosing down the spill. Remove the adsorbent materials promptly and dispose of properly. „ For larger spills, a private spill cleanup company or Hazmat team may be necessary. „ See fact sheet SC-11 Spill Prevention, Control, and Clean Up. Field Program General „ Develop clear protocols and lines of communication for effectively prohibiting non- stormwater discharges, especially ones that involve more than one jurisdiction and those that are not classified as hazardous, which are often not responded to as effectively as they need to be. „ Stencil storm drains, where applicable, to prevent illegal disposal of pollutants. Storm drain inlets should have messages such as “Dump No Waste Drains to Stream” stenciled next to them to warn against ignorant or intentional dumping of pollutants into the storm drainage system. „ See SC-74 Stormwater Drainage System Maintenance for additional information. SC-10 Non-Stormwater Discharges 4 of 11 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Field Inspection „ Regularly inspect and clean up hot spots and other storm drainage areas where illegal dumping and disposal occurs. „ During routine field program maintenance field staff should look for evidence of illegal discharges or illicit connection: - Is there evidence of spills such as paints, discoloring, etc. - Are there any odors associated with the drainage system - Record locations of apparent illegal discharges/illicit connections and notify appropriate investigating agency. „ If trained, conduct field investigation of non-stormwater discharges to determine whether they pose a threat to water quality. Recommended Complaint Investigation Equipment „ Field Screening Analysis - pH paper or meter - Commercial stormwater pollutant screening kit that can detect for reactive phosphorus, nitrate nitrogen, ammonium nitrogen, specific conductance, and turbidity - Sample jars - Sample collection pole - A tool to remove access hole covers „ Laboratory Analysis - Sample cooler - Ice - Sample jars and labels - Chain of custody forms. „ Documentation - Camera - Notebook - Pens - Notice of Violation forms Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 5 of 11 Municipal www.cabmphandbooks.com - Educational materials Reporting „ A database is useful for defining and tracking the magnitude and location of the problem. „ Report prohibited non-stormwater discharges observed during the course of normal daily activities so they can be investigated, contained and cleaned up or eliminated. „ Document that non-stormwater discharges have been eliminated by recording tests performed, methods used, dates of testing, and any onsite drainage points observed. „ Maintain documentation of illicit connection and illegal dumping incidents, including significant conditionally exempt discharges that are not properly managed. Enforcement „ Educate the responsible party if identified on the impacts of their actions, explain the stormwater requirements, and provide information regarding Best Management Practices (BMP), as appropriate. Initiate follow-up and/or enforcement procedures. „ If an illegal discharge is traced to a commercial, residential or industrial source, conduct the following activities or coordinate the following activities with the appropriate agency: - Contact the responsible party to discuss methods of eliminating the non-stormwater discharge, including disposal options, recycling, and possible discharge to the sanitary sewer (if within POTW limits). - Provide information regarding BMPs to the responsible party, where appropriate. - Begin enforcement procedures, if appropriate. - Continue inspection and follow-up activities until the illicit discharge activity has ceased. „ If an illegal discharge is traced to a commercial or industrial activity, coordinate information on the discharge with the jurisdiction's commercial and industrial facility inspection program. Training „ Train technical staff to identify and document illegal dumping incidents. „ Well-trained employees can reduce human errors that lead to accidental releases or spills. The employee should have the tools and knowledge to immediately begin cleaning up a spill if one should occur. Employees should be familiar with the Spill Prevention Control and Countermeasure Plan. „ Train employees to identify non-stormwater discharges and report them to the appropriate departments. „ Train staff who have the authority to conduct surveillance and inspections, and write citations for those caught illegally dumping. SC-10 Non-Stormwater Discharges 6 of 11 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Train municipal staff responsible for surveillance and inspection in the following: - OSHA-required Health and Safety Training (29 CFR 1910.120) plus annual refresher training (as needed). - OSHA Confined Space Entry training (Cal-OSHA Confined Space, Title 8 and federal OSHA 29 CFR 1910.146). - Procedural training (field screening, sampling, smoke/dye testing, TV inspection). „ Educate the identified responsible party on the impacts of his or her actions. Spill Response and Prevention „ See SC-11 Spill Prevention Control and Clean Up Other Considerations „ The elimination of illegal dumping is dependent on the availability, convenience, and cost of alternative means of disposal. The cost of fees for dumping at a proper waste disposal facility are often more than the fine for an illegal dumping offense, thereby discouraging people from complying with the law. The absence of routine or affordable pickup service for trash and recyclables in some communities also encourages illegal dumping. A lack of understanding regarding applicable laws or the inadequacy of existing laws may also contribute to the problem. „ Municipal codes should include sections prohibiting the discharge of soil, debris, refuse, hazardous wastes, and other pollutants into the storm drain system. „ Many facilities do not have accurate, up-to-date schematic drawings. „ Can be difficult to locate illicit connections especially if there is groundwater infiltration. Requirements Costs „ Eliminating illicit connections can be expensive especially if structural modifications are required such re-plumbing cross connections under an existing slab. „ Minor cost to train field crews regarding the identification of non-stormwater discharges. The primary cost is for a fully integrated program to identify and eliminate illicit connections and illegal dumping. However, by combining with other municipal programs (i.e. pretreatment program) cost may be lowered. „ Municipal cost for containment and disposal may be borne by the discharger. Maintenance Not applicable Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 7 of 11 Municipal www.cabmphandbooks.com Supplemental Information Further Detail of the BMP What constitutes a “non-stormwater” discharge? „ Non-stormwater discharges are discharges not made up entirely of stormwater and include water used directly in the manufacturing process (process wastewater), air conditioning condensate and coolant, non-contact cooling water, cooling equipment condensate, outdoor secondary containment water, vehicle and equipment wash water, landscape irrigation, sink and drinking fountain wastewater, sanitary wastes, or other wastewaters. Permit Requirements „ Current municipal NPDES permits require municipalities to effectively prohibit non- stormwater discharges unless authorized by a separate NPDES permit or allowed in accordance with the current NPDES permit conditions. Typically the current permits allow certain non-stormwater discharges in the storm drain system as long as the discharges are not significant sources of pollutants. In this context the following non-stormwater discharges are typically allowed: - Diverted stream flows; - Rising found waters; - Uncontaminated ground water infiltration (as defined at 40 CFR 35.2005(20)); - Uncontaminated pumped ground water; - Foundation drains; - Springs; - Water from crawl space pumps; - Footing drains; - Air conditioning condensation; - Flows from riparian habitats and wetlands; - Water line and hydrant flushing ; - Landscape irrigation; - Planned and unplanned discharges from potable water sources; - Irrigation water; - Individual residential car washing; and - Lawn watering. SC-10 Non-Stormwater Discharges 8 of 11 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Municipal facilities subject to industrial general permit requirements must include a certification that the stormwater collection system has been tested or evaluated for the presence of non-stormwater discharges. The state’s General Industrial Stormwater Permit requires that non-stormwater discharges be eliminated prior to implementation of the facility’s SWPPP. Illegal Dumping „ Establish a system for tracking incidents. The system should be designed to identify the following: - Illegal dumping hot spots - Types and quantities (in some cases) of wastes - Patterns in time of occurrence (time of day/night, month, or year) - Mode of dumping (abandoned containers, “midnight dumping” from moving vehicles, direct dumping of materials, accidents/spills) - Responsible parties Outreach One of the keys to success of reducing or eliminating illegal dumping is increasing the number of people on the street who are aware of the problem and who have the tools to at least identify the incident, if not correct it. There we a number of ways of accomplishing this: „ Train municipal staff from all departments (public works, utilities, street cleaning, parks and recreation, industrial waste inspection, hazardous waste inspection, sewer maintenance) to recognize and report the incidents. „ Deputize municipal staff who may come into contact with illegal dumping with the authority to write illegal dumping tickets for offenders caught in the act (see below). „ Educate the public. As many as 3 out of 4 people do not understand that in most communities the storm drain does not go to the wastewater treatment plant. Unfortunately, with the heavy emphasis in recent years on public education about solid waste management, including recycling and household hazardous waste, the sewer system (both storm and sanitary) has been the likely recipient of cross-media transfers of waste. „ Provide the public with a mechanism for reporting incidents such as a hot line and/or door hanger (see below). „ Help areas where incidents occur more frequently set up environmental watch programs (like crime watch programs). „ Train volunteers to notice and report the presence and suspected source of an observed pollutant to the appropriate public agency. Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 9 of 11 Municipal www.cabmphandbooks.com What constitutes a “non-stormwater” discharge? „ Non-stormwater discharges are discharges not made up entirely of stormwater and include water used directly in the manufacturing process (process wastewater), air conditioning condensate and coolant, non-contact cooling water, cooling equipment condensate, outdoor secondary containment water, vehicle and equipment wash water, landscape irrigation, sink and drinking fountain wastewater, sanitary wastes, or other wastewaters. Permit Requirements „ Current municipal NPDES permits require municipalities to effectively prohibit non- stormwater discharges unless authorized by a separate NPDES permit or allowed in accordance with the current NPDES permit conditions. Typically the current permits allow certain non-stormwater discharges in the storm drain system as long as the discharges are not significant sources of pollutants. In this context the following non-stormwater discharges are typically allowed: - Diverted stream flows; - Rising found waters; - Uncontaminated ground water infiltration (as defined at 40 CFR 35.2005(20)); - Uncontaminated pumped ground water; - Foundation drains; - Springs; - Water from crawl space pumps; - Footing drains; - Air conditioning condensation; - Flows from riparian habitats and wetlands; - Water line and hydrant flushing ; - Landscape irrigation; - Planned and unplanned discharges from potable water sources; - Irrigation water; - Individual residential car washing; and - Lawn watering. Municipal facilities subject to industrial general permit requirements must include a certification that the stormwater collection system has been tested or evaluated for the presence SC-10 Non-Stormwater Discharges 10 of 11 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com of non-stormwater discharges. The state’s General Industrial Stormwater Permit requires that non-stormwater discharges be eliminated prior to implementation of the facility’s SWPPP. Storm Drain Stenciling „ Stencil storm drain inlets with a message to prohibit illegal dumpings, especially in areas with waste handling facilities. „ Encourage public reporting of improper waste disposal by a HOTLINE number stenciled onto the storm drain inlet. „ See Supplemental Information section of this fact sheet for further detail on stenciling program approach. Oil Recycling „ Contract collection and hauling of used oil to a private licensed used oil hauler/recycler. „ Comply with all applicable state and federal regulations regarding storage, handling, and transport of petroleum products. „ Create procedures for collection such as; collection locations and schedule, acceptable containers, and maximum amounts accepted. „ The California Integrated Waste Management Board has a Recycling Hotline, (800) 553- 2962, that provides information and recycling locations for used oil. Household Hazardous Waste „ Provide household hazardous waste (HHW) collection facilities. Several types of collection approaches are available including permanent, periodic, or mobile centers, curbside collection, or a combination of these systems. Training „ Train municipal employees and contractors in proper and consistent methods for waste disposal. „ Train municipal employees to recognize and report illegal dumping. „ Train employees and subcontractors in proper hazardous waste management. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Non-Stormwater Discharges SC-10 January 2003 California Stormwater BMP Handbook 11 of 11 Municipal www.cabmphandbooks.com Other Considerations „ Federal Regulations (RCRA, SARA, CERCLA) and state regulations exist regarding the disposal of hazardous waste. „ Municipalities are required to have a used oil recycling element and a HHW element within their integrated waste management plan. „ Significant liability issues are involved with the collection, handling, and disposal of HHW. Examples The City of Palo Alto has developed a public participation program for reporting dumping violations. When a concerned citizen or public employee encounters evidence of illegal dumping, a door hanger (similar in format to hotel “Do Not Disturb” signs) is placed on the front doors in the neighborhood. The door hanger notes that a violation has occurred in the neighborhood, informs the reader why illegal dumping is a problem, and notes that illegal dumping carries a significant financial penalty. Information is also provided on what citizens can do as well as contact numbers for more information or to report a violation. The Port of Long Beach has a state of the art database incorporating storm drain infrastructure, potential pollutant sources, facility management practices, and a pollutant tracking system. The State Department of Fish and Game has a hotline for reporting violations called CalTIP (1- 800-952-5400). The phone number may be used to report any violation of a Fish and Game code (illegal dumping, poaching, etc.). The California Department of Toxic Substances Control’s Waste Alert Hotline, 1-800-69TOXIC, can be used to report hazardous waste violations. References and Resources http://www.stormwatercenter.net/ California’s Nonpoint Source Program Plan http://www.co.clark.wa.us/pubworks/bmpman.pdf King County Stormwater Pollution Control Manual - http://dnr.metrokc.gov/wlr/dss/spcm.htm Orange County Stormwater Program, http://www.ocwatersheds.com/stormwater/swp_introduction.asp San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (http://www.projectcleanwater.org) Santa Clara Valley Urban Runoff Pollution Prevention Program http://www.scvurppp-w2k.com/pdf%20documents/PS_ICID.PDF Spill Prevention, Control & Cleanup SC-11 January 2003 California Stormwater BMP Handbook 1 of 6 Municipal www.cabmphandbooks.com Description Spills and leaks, if not properly controlled, can adversely impact the storm drain system and receiving waters. Due to the type of work or the materials involved, many activities that occur either at a municipal facility or as a part of municipal field programs have the potential for accidental spills and leaks. Proper spill response planning and preparation can enable municipal employees to effectively respond to problems when they occur and minimize the discharge of pollutants to the environment. Approach „ An effective spill response and control plan should include: - Spill/leak prevention measures; - Spill response procedures; - Spill cleanup procedures; - Reporting; and - Training „ A well thought out and implemented plan can prevent pollutants from entering the storm drainage system and can be used as a tool for training personnel to prevent and control future spills as well. Pollution Prevention „ Develop and implement a Spill Prevention Control and Response Plan. The plan should include: Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment Nutrients ; Trash Metals ; Bacteria Oil and Grease ; Organics ; Oxygen Demanding ; SC-11 Spill Prevention, Control & Cleanup 2 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com - A description of the facility, the address, activities and materials involved - Identification of key spill response personnel - Identification of the potential spill areas or operations prone to spills/leaks - Identification of which areas should be or are bermed to contain spills/leaks - Facility map identifying the key locations of areas, activities, materials, structural BMPs, etc. - Material handling procedures - Spill response procedures including: - Assessment of the site and potential impacts - Containment of the material - Notification of the proper personnel and evacuation procedures - Clean up of the site - Disposal of the waste material and - Proper record keeping „ Product substitution – use less toxic materials (i.e. use water based paints instead of oil based paints) „ Recycle, reclaim, or reuse materials whenever possible. This will reduce the amount of materials that are brought into the facility or into the field. Suggested Protocols Spill/Leak Prevention Measures „ If possible, move material handling indoors, under cover, or away from storm drains or sensitive water bodies. „ Properly label all containers so that the contents are easily identifiable. „ Berm storage areas so that if a spill or leak occurs, the material is contained. „ Cover outside storage areas either with a permanent structure or with a seasonal one such as a tarp so that rain can not come into contact with the materials. „ Check containers (and any containment sumps) often for leaks and spills. Replace containers that are leaking, corroded, or otherwise deteriorating with containers in good condition. Collect all spilled liquids and properly dispose of them. Spill Prevention, Control & Cleanup SC-11 January 2003 California Stormwater BMP Handbook 3 of 6 Municipal www.cabmphandbooks.com „ Store, contain and transfer liquid materials in such a manner that if the container is ruptured or the contents spilled, they will not discharge, flow or be washed into the storm drainage system, surface waters, or groundwater. „ Place drip pans or absorbent materials beneath all mounted taps and at all potential drip and spill locations during the filling and unloading of containers. Any collected liquids or soiled absorbent materials should be reused/recycled or properly disposed of. „ For field programs, only transport the minimum amount of material needed for the daily activities and transfer materials between containers at a municipal yard where leaks and spill are easier to control. „ If paved, sweep and clean storage areas monthly, do not use water to hose down the area unless all of the water will be collected and disposed of properly. „ Install a spill control device (such as a tee section) in any catch basins that collect runoff from any storage areas if the materials stored are oil, gas, or other materials that separate from and float on water. This will allow for easier cleanup if a spill occurs. „ If necessary, protect catch basins while conducting field activities so that if a spill occurs, the material will be contained. Training „ Educate employees about spill prevention, spill response and cleanup on a routine basis. „ Well-trained employees can reduce human errors that lead to accidental releases or spills: - The employees should have the tools and knowledge to immediately begin cleaning up a spill if one should occur. - Employees should be familiar with the Spill Prevention Control and Countermeasure Plan if one is available. „ Training of staff from all municipal departments should focus on recognizing and reporting potential or current spills/leaks and who they should contact. „ Employees responsible for aboveground storage tanks and liquid transfers for large bulk containers should be thoroughly familiar with the Spill Prevention Control and Countermeasure Plan and the plan should be readily available. Spill Response and Prevention „ Identify key spill response personnel and train employees on who they are. „ Store and maintain appropriate spill cleanup materials in a clearly marked location near storage areas; and train employees to ensure familiarity with the site’s spill control plan and/or proper spill cleanup procedures. „ Locate spill cleanup materials, such as absorbents, where they will be readily accessible (e.g. near storage and maintenance areas, on field trucks). SC-11 Spill Prevention, Control & Cleanup 4 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Follow the Spill Prevention Control and Countermeasure Plan if one is available. „ If a spill occurs, notify the key spill response personnel immediately. If the material is unknown or hazardous, the local fire department may also need to be contacted. „ If safe to do so, attempt to contain the material and block the nearby storm drains so that the area impacted is minimized. If the material is unknown or hazardous wait for properly trained personnel to contain the materials. „ Perform an assessment of the area where the spill occurred and the downstream area that it could impact. Relay this information to the key spill response and clean up personnel. Spill Cleanup Procedures „ Small non-hazardous spills - Use a rag, damp cloth or absorbent materials for general clean up of liquids - Use brooms or shovels for the general clean up of dry materials - If water is used, it must be collected and properly disposed of. The wash water can not be allowed to enter the storm drain. - Dispose of any waste materials properly - Clean or dispose of any equipment used to clean up the spill properly „ Large non-hazardous spills - Use absorbent materials for general clean up of liquids - Use brooms, shovels or street sweepers for the general clean up of dry materials - If water is used, it must be collected and properly disposed of. The wash water can not be allowed to enter the storm drain. - Dispose of any waste materials properly - Clean or dispose of any equipment used to clean up the spill properly „ For hazardous or very large spills, a private cleanup company or Hazmat team may need to be contacted to assess the situation and conduct the cleanup and disposal of the materials. „ Chemical cleanups of material can be achieved with the use of absorbents, gels, and foams. Remove the adsorbent materials promptly and dispose of according to regulations. „ If the spilled material is hazardous, then the used cleanup materials are also hazardous and must be sent to a certified laundry (rags) or disposed of as hazardous waste. Reporting „ Report any spills immediately to the identified key municipal spill response personnel. Spill Prevention, Control & Cleanup SC-11 January 2003 California Stormwater BMP Handbook 5 of 6 Municipal www.cabmphandbooks.com „ Report spills in accordance with applicable reporting laws. Spills that pose an immediate threat to human health or the environment must be reported immediately to the Office of Emergency Service (OES) „ Spills that pose an immediate threat to human health or the environment may also need to be reported within 24 hours to the Regional Water Quality Control Board. „ Federal regulations require that any oil spill into a water body or onto an adjoining shoreline be reported to the National Response Center (NRC) at 800-424-8802 (24 hour) „ After the spill has been contained and cleaned up, a detailed report about the incident should be generated and kept on file (see the section on Reporting below). The incident may also be used in briefing staff about proper procedures Other Considerations „ State regulations exist for facilities with a storage capacity of 10,000 gallons or more of petroleum to prepare a Spill Prevention Control and Countermeasure Plan (SPCC) Plan (Health & Safety Code Chapter 6.67). „ State regulations also exist for storage of hazardous materials (Health & Safety Code Chapter 6.95), including the preparation of area and business plans for emergency response to the releases or threatened releases. „ Consider requiring smaller secondary containment areas (less than 200 sq. ft.) to be connected to the sanitary sewer, if permitted to do so, prohibiting any hard connections to the storm drain. Requirements Costs „ Will vary depending on the size of the facility and the necessary controls. „ Prevention of leaks and spills is inexpensive. Treatment and/or disposal of wastes, contaminated soil and water is very expensive Maintenance „ This BMP has no major administrative or staffing requirements. However, extra time is needed to properly handle and dispose of spills, which results in increased labor costs Supplemental Information Further Detail of the BMP Reporting Record keeping and internal reporting represent good operating practices because they can increase the efficiency of the response and containment of a spill. A good record keeping system helps the municipality minimize incident recurrence, correctly respond with appropriate containment and cleanup activities, and comply with legal requirements. A record keeping and reporting system should be set up for documenting spills, leaks, and other discharges, including discharges of hazardous substances in reportable quantities. Incident records describe the quality and quantity of non-stormwater discharges to the storm drain. SC-11 Spill Prevention, Control & Cleanup 6 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com These records should contain the following information: „ Date and time of the incident „ Weather conditions „ Duration of the spill/leak/discharge „ Cause of the spill/leak/discharge „ Response procedures implemented „ Persons notified „ Environmental problems associated with the spill/leak/discharge Separate record keeping systems should be established to document housekeeping and preventive maintenance inspections, and training activities. All housekeeping and preventive maintenance inspections should be documented. Inspection documentation should contain the following information: „ The date and time the inspection was performed „ Name of the inspector „ Items inspected „ Problems noted „ Corrective action required „ Date corrective action was taken Other means to document and record inspection results are field notes, timed and dated photographs, videotapes, and drawings and maps. Examples The City of Palo Alto includes spill prevention and control as a major element of its highly effective program for municipal vehicle maintenance shops. References and Resources King County Stormwater Pollution Control Manual - http://dnr.metrokc.gov/wlr/dss/spcm.htm Orange County Stormwater Program http://www.ocwatersheds.com/stormwater/swp_introduction.asp San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (URMP) http://www.projectcleanwater.org/pdf/Model%20Program%20Municipal%20Facilities.pdf Vehicle and Equipment Cleaning SC-21 January 2003 California Stormwater BMP Handbook 1 of 4 Municipal www.cabmphandbooks.com Description Wash water from vehicle and equipment cleaning activities performed outdoors or in areas where wash water flows onto the ground can contribute toxic hydrocarbons and other organic compounds, oils and greases, nutrients, phosphates, heavy metals, and suspended solids to stormwater runoff. Use of the procedures outlined below can prevent or reduce the discharge of pollutants to stormwater during vehicle and equipment cleaning. Approach Reduce potential for pollutant discharge through source control pollution prevention and BMP implementation. Successful implementation depends on effective training of employees on applicable BMPs and general pollution prevention strategies and objectives Pollution Prevention „ If possible, use properly maintained off-site commercial washing and steam cleaning businesses whenever possible. These businesses are better equipped to handle and properly dispose of the wash waters. „ Good housekeeping practices can minimize the risk of contamination from wash water discharges. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria Oil and Grease ; Organics ; Oxygen Demanding Photo Credit: Geoff Brosseau SC-21 Vehicle and Equipment Cleaning 2 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Suggested Protocols General „ Use biodegradable, phosphate-free detergents for washing vehicles as appropriate. „ Mark the area clearly as a wash area. „ Post signs stating that only washing is allowed in wash area and that discharges to the storm drain are prohibited. „ Provide a trash container in wash area. „ Map on-site storm drain locations to avoid discharges to the storm drain system. „ Emphasize the connection between the storm drain system and runoff and help reinforce that car washing activities can have an affect on local water quality. This can be accomplished through storm drain stenciling programs. Vehicle and Equipment Cleaning „ Design wash areas to properly collect and dispose of wash water when engine cleaning is conducted and when chemical additives, solvents, or degreasers are used. This may include installation of sumps or drain lines to collect wash water or construction of a berm around the designated area and grading of the area to collect wash water as well as prevent stormwater run-on. „ Consider washing vehicles and equipment inside the building if washing/cleaning must occur on-site. This will help to control the targeted constituents by directing them to the sanitary sewer. „ If washing must occur on-site and outdoor: - Use designated paved wash areas. Designated wash areas must be well marked with signs indicating where and how washing must be done. This area must be covered or bermed to collect the wash water and graded to direct the wash water to a treatment or disposal facility. - Oil changes and other engine maintenance cannot be conducted in the designated washing area. Perform these activities in a place designated for such activities. - Cover the wash area when not in use to prevent contact with rain water. „ Use hoses with nozzles that automatically turn off when left unattended. „ Perform pressure cleaning and steam cleaning off-site to avoid generating runoff with high pollutant concentrations. If done on-site, no pressure cleaning and steam cleaning should be done in areas designated as wellhead protection areas for public water supply. Disposal „ Consider filtering and recycling wash water. Vehicle and Equipment Cleaning SC-21 January 2003 California Stormwater BMP Handbook 3 of 4 Municipal www.cabmphandbooks.com „ Discharge equipment wash water to the sanitary sewer, a holding tank, or a process treatment system, regardless of the washing method used. „ Discharge vehicle wash water to (1) the sanitary sewer, a holding tank, or process treatment system or (2) an enclosed recycling system. „ Discharge wash water to sanitary sewer only after contacting the local sewer authority to find out if pretreatment is required. Training „ Train employees on proper cleaning and wash water disposal procedures and conduct “refresher” courses on a regular basis. „ Train staff on proper maintenance measures for the wash area. „ Train employees and contractors on proper spill containment and cleanup. The employee should have the tools and knowledge to immediately begin cleaning up a spill if one should occur. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control and Cleanup. „ Keep your Spill Prevention Control and Counter Measure (SPCC) Plan up-to-date, and implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Clean up spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations (Limitations and Regulations) „ Some municipalities may require pretreatment and monitoring of wash water discharges to the sanitary sewer. „ Steam cleaning can generate significant pollutant concentrations requiring that careful consideration be given to the environmental impacts and compliance issues related to steam cleaning. „ Most car washing best management practices are inexpensive, and rely more on good housekeeping practices (where vehicles are washed, planning for the collection of wash water) than on expensive technology. However, the construction of a specialized area for vehicle washing can be expensive for municipal facilities. Also, for facilities that cannot recycle their wash water the cost of pre-treating wash water through either structural practices or planning for collection and hauling of contaminated water to sewage treatment plants can represent a cost limitation. Requirements Costs „ Capital costs vary depending on measures implemented SC-21 Vehicle and Equipment Cleaning 4 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com - Low cost ($500-1,000) for berm construction, - Medium cost ($5,000-20,000) for plumbing modifications (including re-routing discharge to sanitary sewer and installing simple sump). - High cost ($30,000-150,000) for on-site treatment and recycling. „ O&M costs increase with increasing capital investment. Maintenance „ Berm repair and patching. „ Sweep washing areas frequently to remove solid debris. „ Inspect and maintain sumps, oil/water separators, and on-site treatment/recycling units. Supplemental Information Design Considerations Designated Cleaning Areas „ Washing operations outside should be conducted in a designated wash area having the following characteristics: - Paved with Portland cement concrete, - Covered and bermed to prevent contact with stormwater and contain wash water, - Sloped for wash water collection, - Equipped with an oil/water separator, if necessary. Examples The City of Palo Alto has an effective program for commercial vehicle service facilities. Many of the program’s elements, including specific BMP guidance and lists of equipment suppliers, are applicable to industrial vehicle service facilities. The U.S. Postal Service in West Sacramento has a new vehicle wash system that collects, filters, and recycles the wash water. References and Resources http://www.stormwatercenter.net/ King County - ftp://dnr.metrokc.gov/wlr/dss/spcm/Chapter%203.PDF Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (URMP) http://www.projectcleanwater.org/pdf/Model%20Program%20Municipal%20Facilities.pdf Waste Handling & Disposal SC-34 January 2003 California Stormwater BMP Handbook 1 of 5 Municipal www.cabmphandbooks.com Description Improper storage and handling of solid wastes can allow toxic compounds, oils and greases, heavy metals, nutrients, suspended solids, and other pollutants to enter stormwater runoff. The discharge of pollutants to stormwater from waste handling and disposal can be prevented and reduced by tracking waste generation, storage, and disposal; reducing waste generation and disposal through source reduction, re-use, and recycling; and preventing runon and runoff. Approach Pollution Prevention „ Reduction in the amount of waste generated can be accomplished using the following source controls such as: - Production planning and sequencing - Process or equipment modification - Raw material substitution or elimination - Loss prevention and housekeeping - Waste segregation and separation - Close loop recycling „ Establish a material tracking system to increase awareness about material usage. This may reduce spills and minimize contamination, thus reducing the amount of waste produced. „ Recycle materials whenever possible. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-34 Waste Handling & Disposal 2 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Suggested Protocols General „ Cover storage containers with leak proof lids or some other means. If waste is not in containers, cover all waste piles (plastic tarps are acceptable coverage) and prevent stormwater runon and runoff with a berm. The waste containers or piles must be covered except when in use. „ Use drip pans or absorbent materials whenever grease containers are emptied by vacuum trucks or other means. Grease cannot be left on the ground. Collected grease must be properly disposed of as garbage. „ Check storage containers weekly for leaks and to ensure that lids are on tightly. Replace any that are leaking, corroded, or otherwise deteriorating. „ Sweep and clean the storage area regularly. If it is paved, do not hose down the area to a storm drain. „ Dispose of rinse and wash water from cleaning waste containers into a sanitary sewer if allowed by the local sewer authority. Do not discharge wash water to the street or storm drain. „ Transfer waste from damaged containers into safe containers. „ Take special care when loading or unloading wastes to minimize losses. Loading systems can be used to minimize spills and fugitive emission losses such as dust or mist. Vacuum transfer systems can minimize waste loss. Controlling Litter „ Post “No Littering” signs and enforce anti-litter laws. „ Provide a sufficient number of litter receptacles for the facility. „ Clean out and cover litter receptacles frequently to prevent spillage. Waste Collection „ Keep waste collection areas clean. „ Inspect solid waste containers for structural damage or leaks regularly. Repair or replace damaged containers as necessary. „ Secure solid waste containers; containers must be closed tightly when not in use. „ Place waste containers under cover if possible. „ Do not fill waste containers with washout water or any other liquid. „ Ensure that only appropriate solid wastes are added to the solid waste container. Certain wastes such as hazardous wastes, appliances, fluorescent lamps, pesticides, etc. may not be Waste Handling & Disposal SC-34 January 2003 California Stormwater BMP Handbook 3 of 5 Municipal www.cabmphandbooks.com disposed of in solid waste containers (see chemical/ hazardous waste collection section below). „ Do not mix wastes; this can cause chemical reactions, make recycling impossible, and complicate disposal. Good Housekeeping „ Use all of the product before disposing of the container. „ Keep the waste management area clean at all times by sweeping and cleaning up spills immediately. „ Use dry methods when possible (e.g. sweeping, use of absorbents) when cleaning around restaurant/food handling dumpster areas. If water must be used after sweeping/using absorbents, collect water and discharge through grease interceptor to the sewer. „ Stencil storm drains on the facility’s property with prohibitive message regarding waste disposal. Chemical/Hazardous Wastes „ Select designated hazardous waste collection areas on-site. „ Store hazardous materials and wastes in covered containers protected from vandalism, and in compliance with fire and hazardous waste codes. „ Place hazardous waste containers in secondary containment. „ Make sure that hazardous waste is collected, removed, and disposed of only at authorized disposal areas. Runon/Runoff Prevention „ Prevent stormwater runon from entering the waste management area by enclosing the area or building a berm around the area. „ Prevent the waste materials from directly contacting rain. „ Cover waste piles with temporary covering material such as reinforced tarpaulin, polyethylene, polyurethane, polypropyleneor hypalon. „ Cover the area with a permanent roof if feasible. „ Cover dumpsters to prevent rain from washing waste out of holes or cracks in the bottom of the dumpster. „ Move the activity indoor after ensuring all safety concerns such as fire hazard and ventilation are addressed. Inspection SC-34 Waste Handling & Disposal 4 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Inspect and replace faulty pumps or hoses regularly to minimize the potential of releases and spills. „ Check waste management areas for leaking containers or spills. „ Repair leaking equipment including valves, lines, seals, or pumps promptly. Training „ Train staff pollution prevention measures and proper disposal methods. „ Train employees and contractors proper spill containment and cleanup. The employee should have the tools and knowledge to immediately begin cleaning up a spill if one should occur. „ Train employees and subcontractors in proper hazardous waste management. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Keep your Spill Prevention Control and countermeasure (SPCC) plan up-to-date, and implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. „ Vehicles transporting waste should have spill prevention equipment that can prevent spills during transport. The spill prevention equipment includes: - Vehicles equipped with baffles for liquid waste - Trucks with sealed gates and spill guards for solid waste Other Considerations „ Hazardous waste cannot be re-used or recycled; it must be disposed of by a licensed hazardous waste hauler. Requirements Costs „ Capital and operation and maintenance costs will vary substantially depending on the size of the facility and the types of waste handled. Costs should be low if there is an inventory program in place. Maintenance „ None except for maintaining equipment for material tracking program. Waste Handling & Disposal SC-34 January 2003 California Stormwater BMP Handbook 5 of 5 Municipal www.cabmphandbooks.com Supplemental Information Further Detail of the BMP Land Treatment System „ Minimize the runoff of polluted stormwater from land application of municipal waste on-site by: - Choosing a site where slopes are under 6%, the soil is permeable, there is a low water table, it is located away from wetlands or marshes, there is a closed drainage system. - Avoiding application of waste to the site when it is raining or when the ground is saturated with water. - Growing vegetation on land disposal areas to stabilize soils and reduce the volume of surface water runoff from the site. - Maintaining adequate barriers between the land application site and the receiving waters. Planted strips are particularly good. - Using erosion control techniques such as mulching and matting, filter fences, straw bales, diversion terracing, and sediment basins. - Performing routine maintenance to ensure the erosion control or site stabilization measures are working. References and Resources King County Stormwater Pollution Control Manual - http://dnr.metrokc.gov/wlr/dss/spcm.htm Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Pollution from Surface Cleaning Folder. 1996. Bay Area Stormwater Management Agencies Associations (BASMAA). On-line: http://www.basmaa.org Building & Grounds Maintenance SC-41 January 2003 California Stormwater BMP Handbook 1 of 5 Municipal www.cabmphandbooks.com Description Stormwater runoff from building and grounds maintenance activities can be contaminated with toxic hydrocarbons in solvents, fertilizers and pesticides, suspended solids, heavy metals, and abnormal pH. Utilizing the following protocols will prevent or reduce the discharge of pollutants to stormwater from building and grounds maintenance activities by washing and cleaning up with as little water as possible, following good landscape management practices, preventing and cleaning up spills immediately, keeping debris from entering the storm drains, and maintaining the stormwater collection system. Approach Pollution Prevention „ Switch to non-toxic chemicals for maintenance when possible. „ Choose cleaning agents that can be recycled. „ Encourage proper lawn management and landscaping, including use of native vegetation. „ Encourage use of Integrated Pest Management techniques for pest control. „ Encourage proper onsite recycling of yard trimmings. „ Recycle residual paints, solvents, lumber, and other material as much as possible. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-41 Building & Grounds Maintenance 2 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Suggested Protocols Pressure Washing of Buildings, Rooftops, and Other Large Objects „ In situations where soaps or detergents are used and the surrounding area is paved, pressure washers must use a waste water collection device that enables collection of wash water and associated solids. A sump pump, wet vacuum or similarly effective device must be used to collect the runoff and loose materials. The collected runoff and solids must be disposed of properly. „ If soaps or detergents are not used, and the surrounding area is paved, wash water runoff does not have to be collected but must be screened. Pressure washers must use filter fabric or some other type of screen on the ground and/or in he catch basin to trap the particles in wash water runoff. „ If you are pressure washing on a grassed area (with or without soap), runoff must be dispersed as sheet flow as much as possible, rather than as a concentrated stream. The wash runoff must remain on the grass and not drain to pavement. Ensure that this practice does not kill grass. Landscaping Activities „ Do not apply any chemicals (insecticide, herbicide, or fertilizer) directly to surface waters, unless the application is approved and permitted by the state. „ Dispose of grass clippings, leaves, sticks, or other collected vegetation as garbage, or by composting. Do not dispose of collected vegetation into waterways or storm drainage systems. „ Use mulch or other erosion control measures on exposed soils. „ Check irrigation schedules so pesticides will not be washed away and to minimize non- stormwater discharge. Building Repair, Remodeling, and Construction „ Do not dump any toxic substance or liquid waste on the pavement, the ground, or toward a storm drain. „ Use ground or drop cloths underneath outdoor painting, scraping, and sandblasting work, and properly dispose of collected material daily. „ Use a ground cloth or oversized tub for activities such as paint mixing and tool cleaning. „ Clean paint brushes and tools covered with water-based paints in sinks connected to sanitary sewers or in portable containers that can be dumped into a sanitary sewer drain. Brushes and tools covered with non-water-based paints, finishes, or other materials must be cleaned in a manner that enables collection of used solvents (e.g., paint thinner, turpentine, etc.) for recycling or proper disposal. Building & Grounds Maintenance SC-41 January 2003 California Stormwater BMP Handbook 3 of 5 Municipal www.cabmphandbooks.com „ Use a storm drain cover, filter fabric, or similarly effective runoff control mechanism if dust, grit, wash water, or other pollutants may escape the work area and enter a catch basin. The containment device(s) must be in place at the beginning of the work day, and accumulated dirty runoff and solids must be collected and disposed of before removing the containment device(s) at the end of the work day. „ If you need to de-water an excavation site, you may need to filter the water before discharging to a catch basin or off-site. In which case you should direct the water through hay bales and filter fabric or use other sediment filters or traps. „ Store toxic material under cover with secondary containment during precipitation events and when not in use. A cover would include tarps or other temporary cover material. Mowing, Trimming, and Planting „ Dispose of leaves, sticks, or other collected vegetation as garbage, by composting or at a permitted landfill. Do not dispose of collected vegetation into waterways or storm drainage systems. „ Use mulch or other erosion control measures when soils are exposed. „ Place temporarily stockpiled material away from watercourses and drain inlets, and berm or cover stockpiles to prevent material releases to the storm drain system. „ Consider an alternative approach when bailing out muddy water; do not put it in the storm drain, pour over landscaped areas. „ Use hand or mechanical weeding where practical. Fertilizer and Pesticide Management „ Follow all federal, state, and local laws and regulations governing the use, storage, and disposal of fertilizers and pesticides and training of applicators and pest control advisors. „ Follow manufacturers’ recommendations and label directions. Pesticides must never be applied if precipitation is occuring or predicted. Do not apply insecticides within 100 feet of surface waters such as lakes, ponds, wetlands, and streams. „ Use less toxic pesticides that will do the job, whenever possible. Avoid use of copper-based pesticides if possible. „ Do not use pesticides if rain is expected. „ Do not mix or prepare pesticides for application near storm drains. „ Use the minimum amount needed for the job. „ Calibrate fertilizer distributors to avoid excessive application. „ Employ techniques to minimize off-target application (e.g. spray drift) of pesticides, including consideration of alternative application techniques. SC-41 Building & Grounds Maintenance 4 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Apply pesticides only when wind speeds are low. „ Work fertilizers into the soil rather than dumping or broadcasting them onto the surface. „ Irrigate slowly to prevent runoff and then only as much as is needed. „ Clean pavement and sidewalk if fertilizer is spilled on these surfaces before applying irrigation water. „ Dispose of empty pesticide containers according to the instructions on the container label. „ Use up the pesticides. Rinse containers, and use rinse water as product. Dispose of unused pesticide as hazardous waste. „ Implement storage requirements for pesticide products with guidance from the local fire department and County Agricultural Commissioner. Provide secondary containment for pesticides. Inspection „ Inspect irrigation system periodically to ensure that the right amount of water is being applied and that excessive runoff is not occurring. Minimize excess watering, and repair leaks in the irrigation system as soon as they are observed. Training „ Educate and train employees on use of pesticides and in pesticide application techniques to prevent pollution. „ Train employees and contractors in proper techniques for spill containment and cleanup. „ Be sure the frequency of training takes into account the complexity of the operations and the nature of the staff. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup „ Keep your Spill Prevention Control and countermeasure (SPCC) plan up-to-date, and implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ Alternative pest/weed controls may not be available, suitable, or effective in many cases. Building & Grounds Maintenance SC-41 January 2003 California Stormwater BMP Handbook 5 of 5 Municipal www.cabmphandbooks.com Requirements Costs „ Overall costs should be low in comparison to other BMPs. Maintenance „ Sweep paved areas regularly to collect loose particles, and wipe up spills with rags and other absorbent material immediately, do not hose down the area to a storm drain. Supplemental Information Further Detail of the BMP Fire Sprinkler Line Flushing Building fire sprinkler line flushing may be a source of non-stormwater runoff pollution. The water entering the system is usually potable water though in some areas it may be non-potable reclaimed wastewater. There are subsequent factors that may drastically reduce the quality of the water in such systems. Black iron pipe is usually used since it is cheaper than potable piping but it is subject to rusting and results in lower quality water. Initially the black iron pipe has an oil coating to protect it from rusting between manufacture and installation; this will contaminate the water from the first flush but not from subsequent flushes. Nitrates, poly- phosphates and other corrosion inhibitors, as well as fire suppressants and antifreeze may be added to the sprinkler water system. Water generally remains in the sprinkler system a long time, typically a year, between flushes and may accumulate iron, manganese, lead, copper, nickel and zinc. The water generally becomes anoxic and contains living and dead bacteria and breakdown products from chlorination. This may result in a significant BOD problem and the water often smells. Consequently dispose fire sprinkler line flush water into the sanitary sewer. Do not allow discharge to storm drain or infiltration due to potential high levels of pollutants in fire sprinkler line water. References and Resources California’s Nonpoint Source Program Plan http://www.swrcb.ca.gov/nps/index.html King County - ftp://dnr.metrokc.gov/wlr/dss/spcm/Chapter%203.PDF Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Mobile Cleaners Pilot Program: Final Report. 1997. Bay Area Stormwater Management Agencies Association (BASSMA) http://www.basmaa.org/ Pollution from Surface Cleaning Folder. 1996. Bay Area Stormwater Management Agencies Association (BASMAA) http://www.basmaa.org/ San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (URMP) - http://www.projectcleanwater.org/pdf/Model%20Program%20Municipal%20Facilities.pdf Parking/Storage Area Maintenance SC-43 January 2003 California Stormwater BMP Handbook 1 of 4 Municipal www.cabmphandbooks.com Description Parking lots and storage areas can contribute a number of substances, such as trash, suspended solids, hydrocarbons, oil and grease, and heavy metals that can enter receiving waters through stormwater runoff or non-stormwater discharges. The following protocols are intended to prevent or reduce the discharge of pollutants from parking/storage areas and include using good housekeeping practices, following appropriate cleaning BMPs, and training employees. Approach Pollution Prevention „ Encourage alternative designs and maintenance strategies for impervious parking lots. (See New Development and Redevelopment BMP Handbook). „ Keep accurate maintenance logs to evaluate BMP implementation. Suggested Protocols General „ Keep the parking and storage areas clean and orderly. Remove debris in a timely fashion. „ Allow sheet runoff to flow into biofilters (vegetated strip and swale) and/or infiltration devices. „ Utilize sand filters or oleophilic collectors for oily waste in low concentrations. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-43 Parking/Storage Area Maintenance 2 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Arrange rooftop drains to prevent drainage directly onto paved surfaces. „ Design lot to include semi-permeable hardscape. Controlling Litter „ Post “No Littering” signs and enforce anti-litter laws. „ Provide an adequate number of litter receptacles. „ Clean out and cover litter receptacles frequently to prevent spillage. „ Provide trash receptacles in parking lots to discourage litter. „ Routinely sweep, shovel and dispose of litter in the trash. Surface cleaning „ Use dry cleaning methods (e.g. sweeping or vacuuming) to prevent the discharge of pollutants into the stormwater conveyance system. „ Establish frequency of public parking lot sweeping based on usage and field observations of waste accumulation. „ Sweep all parking lots at least once before the onset of the wet season. „ If water is used follow the procedures below: - Block the storm drain or contain runoff. - Wash water should be collected and pumped to the sanitary sewer or discharged to a pervious surface, do not allow wash water to enter storm drains. - Dispose of parking lot sweeping debris and dirt at a landfill. „ When cleaning heavy oily deposits: - Use absorbent materials on oily spots prior to sweeping or washing. - Dispose of used absorbents appropriately. Surface Repair „ Pre-heat, transfer or load hot bituminous material away from storm drain inlets. „ Apply concrete, asphalt, and seal coat during dry weather to prevent contamination form contacting stormwater runoff. „ Cover and seal nearby storm drain inlets (with waterproof material or mesh) and manholes before applying seal coat, slurry seal, etc., where applicable. Leave covers in place until job is complete and until all water from emulsified oil sealants has drained or evaporated. Clean any debris from these covered manholes and drains for proper disposal. Parking/Storage Area Maintenance SC-43 January 2003 California Stormwater BMP Handbook 3 of 4 Municipal www.cabmphandbooks.com „ Use only as much water as necessary for dust control, to avoid runoff. „ Catch drips from paving equipment that is not in use with pans or absorbent material placed under the machines. Dispose of collected material and absorbents properly. Inspection „ Have designated personnel conduct inspections of the parking facilities and stormwater conveyance systems associated with them on a regular basis. „ Inspect cleaning equipment/sweepers for leaks on a regular basis. Training „ Provide regular training to field employees and/or contractors regarding cleaning of paved areas and proper operation of equipment. „ Train employees and contractors in proper techniques for spill containment and cleanup. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Keep your Spill Prevention Control and countermeasure (SPCC) plan up-to-date, nad implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ Limitations related to sweeping activities at large parking facilities may include high equipment costs, the need for sweeper operator training, and the inability of current sweeper technology to remove oil and grease. Requirements Costs Cleaning/sweeping costs can be quite large, construction and maintenance of stormwater structural controls can be quite expensive as well. Maintenance „ Sweep parking lot to minimize cleaning with water. „ Clean out oil/water/sand separators regularly, especially after heavy storms. „ Clean parking facilities on a regular basis to prevent accumulated wastes and pollutants from being discharged into conveyance systems during rainy conditions. SC-43 Parking/Storage Area Maintenance 4 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Supplemental Information Further Detail of the BMP Surface Repair Apply concrete, asphalt, and seal coat during dry weather to prevent contamination form contacting stormwater runoff. Where applicable, cover and seal nearby storm drain inlets (with waterproof material or mesh) and manholes before applying seal coat, slurry seal, etc. Leave covers in place until job is complete and until all water from emulsified oil sealants has drained or evaporated. Clean any debris from these covered manholes and drains for proper disposal. Use only as much water as necessary for dust control, to avoid runoff. References and Resources http://www.stormwatercenter.net/ California’s Nonpoint Source Program Plan http://www.swrcb.ca.gov/nps/index.html Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality control Board. July 1998 (Revised February 2002 by the California Coastal Commission). Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Oregon Association of Clean Water Agencies. Oregon Municipal Stormwater Toolbox for Maintenance Practices. June 1998. Pollution from Surface Cleaning Folder. 1996. Bay Area Stormwater Management Agencies Association (BASMAA) http://www.basma.org San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (URMP) http://www.projectcleanwater.org/pdf/Model%20Program%20Municipal%20Facilities.pdf Housekeeping Practices SC-60 January 2003 California Stormwater BMP Handbook 1 of 3 Municipal www.cabmphandbooks.com Description Promote efficient and safe housekeeping practices (storage, use, and cleanup) when handling potentially harmful materials such as fertilizers, pesticides, cleaning solutions, paint products, automotive products, and swimming pool chemicals. Related information is provided in BMP fact sheets SC-11 Spill Prevention, Control & Cleanup and SC-34 Waste Handling & Disposal. Approach Pollution Prevention „ Purchase only the amount of material that will be needed for foreseeable use. In most cases this will result in cost savings in both purchasing and disposal. See SC-61 Safer Alternative Products for additional information. „ Be aware of new products that may do the same job with less environmental risk and for less or the equivalent cost. Total cost must be used here; this includes purchase price, transportation costs, storage costs, use related costs, clean up costs and disposal costs. Suggested Protocols General „ Keep work sites clean and orderly. Remove debris in a timely fashion. Sweep the area. „ Dispose of wash water, sweepings, and sediments, properly. „ Recycle or dispose of fluids properly. „ Establish a daily checklist of office, yard and plant areas to confirm cleanliness and adherence to proper storage and security. Specific employees should be assigned specific inspection responsibilities and given the authority to remedy any problems found. „ Post waste disposal charts in appropriate locations detailing for each waste its hazardous nature (poison, corrosive, flammable), prohibitions on its disposal (dumpster, drain, sewer) and the recommended disposal method (recycle, sewer, burn, storage, landfill). „ Summarize the chosen BMPs applicable to your operation and post them in appropriate conspicuous places. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-60 Housekeeping Practices 2 of 3 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Require a signed checklist from every user of any hazardous material detailing amount taken, amount used, amount returned and disposal of spent material. „ Do a before audit of your site to establish baseline conditions and regular subsequent audits to note any changes and whether conditions are improving or deteriorating. „ Keep records of water, air and solid waste quantities and quality tests and their disposition. „ Maintain a mass balance of incoming, outgoing and on hand materials so you know when there are unknown losses that need to be tracked down and accounted for. „ Use and reward employee suggestions related to BMPs, hazards, pollution reduction, work place safety, cost reduction, alternative materials and procedures, recycling and disposal. „ Have, and review regularly, a contingency plan for spills, leaks, weather extremes etc. Make sure all employees know about it and what their role is so that it comes into force automatically. Training „ Train all employees, management, office, yard, manufacturing, field and clerical in BMPs and pollution prevention and make them accountable. „ Train municipal employees who handle potentially harmful materials in good housekeeping practices. „ Train personnel who use pesticides in the proper use of the pesticides. The California Department of Pesticide Regulation license pesticide dealers, certify pesticide applicators and conduct onsite inspections. „ Train employees and contractors in proper techniques for spill containment and cleanup. The employee should have the tools and knowledge to immediately begin cleaning up a spill if one should occur. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Keep your Spill Prevention Control and Countermeasure (SPCC) plant up-to-date, and implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ There are no major limitations to this best management practice. „ There are no regulatory requirements to this BMP. Existing regulations already require municipalities to properly store, use, and dispose of hazardous materials Housekeeping Practices SC-60 January 2003 California Stormwater BMP Handbook 3 of 3 Municipal www.cabmphandbooks.com Requirements Costs „ Minimal cost associated with this BMP. Implementation of good housekeeping practices may result in cost savings as these procedures may reduce the need for more costly BMPs. Maintenance „ Ongoing maintenance required to keep a clean site. Level of effort is a function of site size and type of activities. Supplemental Information Further Detail of the BMP „ The California Integrated Waste Management Board’s Recycling Hotline, 1-800-553-2962, provides information on household hazardous waste collection programs and facilities. Examples There are a number of communities with effective programs. The most pro-active include Santa Clara County and the City of Palo Alto, the City and County of San Francisco, and the Municipality of Metropolitan Seattle (Metro). References and Resources British Columbia Lake Stewardship Society. Best Management Practices to Protect Water Quality from Non-Point Source Pollution. March 2000. http://www.nalms.org/bclss/bmphome.html#bmp King County Stormwater Pollution Control Manual - http://dnr.metrokc.gov/wlr/dss/spcm.htm Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities, Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July, 1998, Revised by California Coastal Commission, February 2002. Orange County Stormwater Program http://www.ocwatersheds.com/stormwater/swp_introduction.asp San Mateo STOPPP - (http://stoppp.tripod.com/bmp.html) Safer Alternative Products SC-61 January 2003 California Stormwater BMP Handbook 1 of 4 Municipal www.cabmphandbooks.com Descriptions Promote the use of less harmful products. Alternatives exist for most product classes including chemical fertilizers, pesticides, cleaning solutions, janitorial chemicals, automotive and paint products, and consumables (batteries, fluorescent lamps). Approach Develop a comprehensive program based on: „ The “Precautionary Principle,” which is an alternative to the "Risk Assessment" model that says it's acceptable to use a potentially harmful product until physical evidence of its harmful effects are established and deemed too costly from an environmental or public health perspective. For instance, a risk assessment approach might say it's acceptable to use a pesticide until there is direct proof of an environmental impact. The Precautionary Principle approach is used to evaluate whether a given product is safe, whether it is really necessary, and whether alternative products would perform just as well. „ Environmentally Preferable Purchasing Program to minimize the purchase of products containing hazardous ingredients used in the facility's custodial services, fleet maintenance, and facility maintenance in favor of using alternate products that pose less risk to employees and to the environment. „ Integrated Pest Management (IPM) or Less-Toxic Pesticide Program, which uses a pest management approach that minimizes the use of toxic chemicals and gets rid of pests by methods that pose a lower risk to employees, the public, and the environment. „ Energy Efficiency Program including no-cost and low-cost energy conservation and efficiency actions that can reduce both energy consumption and electricity bills, along with long-term energy efficiency investments. Consider the following mechanisms for developing and implementing a comprehensive program: „ Policies „ Procedures - Standard operating procedures (SOPs) - Purchasing guidelines and procedures Objectives „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment Nutrients ; Trash Metals ; Bacteria Oil and Grease ; Organics ; Oxygen Demanding SC-61 Safer Alternative Products 2 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com - Bid packages (services and supplies) „ Materials - Preferred or approved product and supplier lists - Product and supplier evaluation criteria - Training sessions and manuals - Fact sheets for employees Training „ Employees who handle potentially harmful materials in the use of safer alternatives. „ Purchasing departments should be encouraged to procure less hazardous materials and products that contain little or no harmful substances or TMDL pollutants. Regulations This BMP has no regulatory requirements. Existing regulations already encourage facilities to reduce the use of hazardous materials through incentives such as reduced: „ Specialized equipment storage and handling requirements, „ Stormwater runoff sampling requirements, „ Training and licensing requirements, and „ Record keeping and reporting requirements. Equipment „ There are no major equipment requirements to this BMP. Limitations „ Alternative products may not be available, suitable, or effective in every case. Requirements Costs „ The primary cost is for staff time to: 1) develop new policies and procedures and 2) educate purchasing departments and employees who handle potentially harmful materials about the availability, procurement, and use of safer alternatives. „ Some alternative products may be slightly more expensive than conventional products. Supplemental Information Employees and contractors / service providers can both be educated about safer alternatives by using information developed by a number of organizations including the references and resources listed below. Safer Alternative Products SC-61 January 2003 California Stormwater BMP Handbook 3 of 4 Municipal www.cabmphandbooks.com The following discussion provides some general information on safer alternatives. More specific information on particular hazardous materials and the available alternatives may be found in the references and resources listed below. „ Automotive products – Less toxic alternatives are not available for many automotive products, especially engine fluids. But there are alternatives to grease lubricants, car polishes, degreasers, and windshield washer solution. Rerefined motor oil is also available. „ Vehicle/Trailer lubrication – Fifth wheel bearings on trucks require routine lubrication. Adhesive lubricants are available to replace typical chassis grease. „ Cleaners – Vegetables-based or citrus-based soaps are available to replace petroleum-based soaps/detergents. „ Paint products – Water-based paints, wood preservatives, stains, and finishes are available. „ Pesticides – Specific alternative products or methods exist to control most insects, fungi, and weeds. „ Chemical Fertilizers – Compost and soil amendments are natural alternatives. „ Consumables – Manufacturers have either reduced or are in the process of reducing the amount of heavy metals in consumables such as batteries and fluorescent lamps. All fluorescent lamps contain mercury, however low-mercury containing lamps are now available from most hardware and lighting stores. Fluorescent lamps are also more energy efficient than the average incandescent lamp. „ Janitorial chemicals – Even biodegradable soap can harm fish and wildlife before it biodegrades. Biodegradable does not mean non-toxic. Safer products and procedures are available for floor stripping and cleaning, as well as carpet, glass, metal, and restroom cleaning and disinfecting. Examples There are a number of business and trade associations, and communities with effective programs. Some of the more prominent are listed below in the references and resources section. References and Resources Note: Many of these references provide alternative products for materials that typically are used inside and disposed to the sanitary sewer as well as alternatives to products that usually end up in the storm drain. General Sustainable Practices and Pollution Prevention Including Pollutant- Specific Information California Department of Toxic Substances Control (www.dtsc.ca.gov) California Integrated Waste Management Board (www.ciwmb.ca.gov) City of Santa Monica (www.santa-monica.org/environment) City of Palo Alto (www.city.palo-alto.ca.us/cleanbay) SC-61 Safer Alternative Products 4 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com City and County of San Francisco, Department of the Environment (www.ci.sf.ca.us/sfenvironment) Earth 911 (www.earth911.org/master.asp) Environmental Finance Center Region IX (www.greenstart.org/efc9) Flex Your Power (www.flexyourpower.ca.gov) GreenBiz.com (www.greenbiz.com) Green Business Program (www.abag.org/bayarea/enviro/gbus/gb.html) Pacific Industrial and Business Association (www.piba.org) Sacramento Clean Water Business Partners (www.sacstormwater.org) USEPA BMP fact sheet – Alternative products (http://cfpub.epa.gov/npdes/stormwater/menuofbmps/poll_2.cfm) USEPA Region IX Pollution Prevention Program (www.epa.gov/region09/p2) Western Regional Pollution Prevention Network (www.westp2net.org) Metals (mercury, copper) National Electrical Manufacturers Association - Environment, Health and Safety (www.nema.org) Sustainable Conservation (www.suscon.org) Auto Recycling Project Brake Pad Partnership Pesticides and Chemical Fertilizers Bio-Integral Resource Center (www.birc.org) California Department of Pesticide Regulation (www.cdpr.ca.gov) University of California Statewide IPM Program (www.ipm.ucdavis.edu/default.html) Dioxins Bay Area Dioxins Project (http://dioxin.abag.ca.gov/) Road and Street Maintenance SC-70 January 2003 California Stormwater BMP Handbook 1 of 9 Municipal www.cabmphandbooks.com Description Streets, roads, and highways are significant sources of pollutants in stormwater discharges, and operation and maintenance (O&M) practices, if not conducted properly, can contribute to the problem. Stormwater pollution from roadway and bridge maintenance should be addressed on a site-specific basis. Use of the procedures outlined below, that address street sweeping and repair, bridge and structure maintenance, and unpaved roads will reduce pollutants in stormwater. Approach Pollution Prevention „ Use the least toxic materials available (e.g. water based paints, gels or sprays for graffiti removal) „ Recycle paint and other materials whenever possible. „ Enlist the help of citizens to keep yard waste, used oil, and other wastes out of the gutter. Suggested Protocols Street Sweeping and Cleaning „ Maintain a consistent sweeping schedule. Provide minimum monthly sweeping of curbed streets. „ Perform street cleaning during dry weather if possible. Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients Trash ; Metals ; Bacteria Oil and Grease ; Organics ; Oxygen Demanding ; SC-70 Road and Street Maintenance 2 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Avoid wet cleaning or flushing of street, and utilize dry methods where possible. „ Consider increasing sweeping frequency based on factors such as traffic volume, land use, field observations of sediment and trash accumulation, proximity to water courses, etc. For example: - Increase the sweeping frequency for streets with high pollutant loadings, especially in high traffic and industrial areas. - Increase the sweeping frequency just before the wet season to remove sediments accumulated during the summer. - Increase the sweeping frequency for streets in special problem areas such as special events, high litter or erosion zones. „ Maintain cleaning equipment in good working condition and purchase replacement equipment as needed. Old sweepers should be replaced with new technologically advanced sweepers (preferably regenerative air sweepers) that maximize pollutant removal. „ Operate sweepers at manufacturer requested optimal speed levels to increase effectiveness. „ To increase sweeping effectiveness consider the following: - Institute a parking policy to restrict parking in problematic areas during periods of street sweeping. - Post permanent street sweeping signs in problematic areas; use temporary signs if installation of permanent signs is not possible. - Develop and distribute flyers notifying residents of street sweeping schedules. „ Regularly inspect vehicles and equipment for leaks, and repair immediately. „ If available use vacuum or regenerative air sweepers in the high sediment and trash areas (typically industrial/commercial). „ Keep accurate logs of the number of curb-miles swept and the amount of waste collected. „ Dispose of street sweeping debris and dirt at a landfill. „ Do not store swept material along the side of the street or near a storm drain inlet. „ Keep debris storage to a minimum during the wet season or make sure debris piles are contained (e.g. by berming the area) or covered (e.g. with tarps or permanent covers). Street Repair and Maintenance Pavement marking „ Schedule pavement marking activities for dry weather. Road and Street Maintenance SC-70 January 2003 California Stormwater BMP Handbook 3 of 9 Municipal www.cabmphandbooks.com „ Develop paint handling procedures for proper use, storage, and disposal of paints. „ Transfer and load paint and hot thermoplastic away from storm drain inlets. „ Provide drop cloths and drip pans in paint mixing areas. „ Properly maintain application equipment. „ Street sweep thermoplastic grindings. Yellow thermoplastic grindings may require special handling as they may contain lead. „ Paints containing lead or tributyltin are considered a hazardous waste and must be disposed of properly. „ Use water based paints whenever possible. If using water based paints, clean the application equipment in a sink that is connected to the sanitary sewer. „ Properly store leftover paints if they are to be kept for the next job, or dispose of properly. Concrete installation and repair „ Schedule asphalt and concrete activities for dry weather. „ Take measures to protect any nearby storm drain inlets and adjacent watercourses, prior to breaking up asphalt or concrete (e.g. place san bags around inlets or work areas). „ Limit the amount of fresh concrete or cement mortar mixed, mix only what is needed for the job. „ Store concrete materials under cover, away from drainage areas. Secure bags of cement after they are open. Be sure to keep wind-blown cement powder away from streets, gutters, storm drains, rainfall, and runoff. „ Return leftover materials to the transit mixer. Dispose of small amounts of hardened excess concrete, grout, and mortar in the trash. „ Do not wash sweepings from exposed aggregate concrete into the street or storm drain. Collect and return sweepings to aggregate base stockpile, or dispose in the trash. „ When making saw cuts in pavement, use as little water as possible and perform during dry weather. Cover each storm drain inlet completely with filter fabric or plastic during the sawing operation and contain the slurry by placing straw bales, sandbags, or gravel dams around the inlets. After the liquid drains or evaporates, shovel or vacuum the slurry residue from the pavement or gutter and remove from site. Alternatively, a small onsite vacuum may be used to pick up the slurry as this will prohibit slurry from reaching storm drain inlets. „ Wash concrete trucks off site or in designated areas on site designed to preclude discharge of wash water to drainage system. SC-70 Road and Street Maintenance 4 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Patching, resurfacing, and surface sealing „ Schedule patching, resurfacing and surface sealing for dry weather. „ Stockpile materials away from streets, gutter areas, storm drain inlets or watercourses. During wet weather, cover stockpiles with plastic tarps or berm around them if necessary to prevent transport of materials in runoff. „ Pre-heat, transfer or load hot bituminous material away from drainage systems or watercourses. „ Where applicable, cover and seal nearby storm drain inlets (with waterproof material or mesh) and maintenance holes before applying seal coat, slurry seal, etc. Leave covers in place until job is complete and until all water from emulsified oil sealants has drained or evaporated. Clean any debris from covered maintenance holes and storm drain inlets when the job is complete. „ Prevent excess material from exposed aggregate concrete or similar treatments from entering streets or storm drain inlets. Designate an area for clean up and proper disposal of excess materials. „ Use only as much water as necessary for dust control, to avoid runoff. „ Sweep, never hose down streets to clean up tracked dirt. Use a street sweeper or vacuum truck. Do not dump vacuumed liquid in storm drains. „ Catch drips from paving equipment that is not in use with pans or absorbent material placed under the machines. Dispose of collected material and absorbents properly. Equipment cleaning maintenance and storage „ Inspect equipment daily and repair any leaks. Place drip pans or absorbent materials under heavy equipment when not in use. „ Perform major equipment repairs at the corporation yard, when practical. „ If refueling or repairing vehicles and equipment must be done onsite, use a location away from storm drain inlets and watercourses. „ Clean equipment including sprayers, sprayer paint supply lines, patch and paving equipment, and mud jacking equipment at the end of each day. Clean in a sink or other area (e.g. vehicle wash area) that is connected to the sanitary sewer. Bridge and Structure Maintenance Paint and Paint Removal „ Transport paint and materials to and from job sites in containers with secure lids and tied down to the transport vehicle. „ Do not transfer or load paint near storm drain inlets or watercourses. Road and Street Maintenance SC-70 January 2003 California Stormwater BMP Handbook 5 of 9 Municipal www.cabmphandbooks.com „ Test and inspect spray equipment prior to starting to paint. Tighten all hoses and connections and do not overfill paint container. „ Plug nearby storm drain inlets prior to starting painting where there is significant risk of a spill reaching storm drains. Remove plugs when job is completed. „ If sand blasting is used to remove paint, cover nearby storm drain inlets prior to starting work. „ Perform work on a maintenance traveler or platform, or use suspended netting or tarps to capture paint, rust, paint removing agents, or other materials, to prevent discharge of materials to surface waters if the bridge crosses a watercourse. If sanding, use a sander with a vacuum filter bag. „ Capture all clean-up water, and dispose of properly. „ Recycle paint when possible (e.g. paint may be used for graffiti removal activities). Dispose of unused paint at an appropriate household hazardous waste facility. Graffiti Removal „ Schedule graffiti removal activities for dry weather. „ Protect nearby storm drain inlets prior to removing graffiti from walls, signs, sidewalks, or other structures needing graffiti abatement. Clean up afterwards by sweeping or vacuuming thoroughly, and/or by using absorbent and properly disposing of the absorbent. „ When graffiti is removed by painting over, implement the procedures under Painting and Paint Removal above. „ Direct runoff from sand blasting and high pressure washing (with no cleaning agents) into a landscaped or dirt area. If such an area is not available, filter runoff through an appropriate filtering device (e.g. filter fabric) to keep sand, particles, and debris out of storm drains. „ If a graffiti abatement method generates wash water containing a cleaning compound (such as high pressure washing with a cleaning compound), plug nearby storm drains and vacuum/pump wash water to the sanitary sewer. „ Consider using a waterless and non-toxic chemical cleaning method for graffiti removal (e.g. gels or spray compounds). Repair Work „ Prevent concrete, steel, wood, metal parts, tools, or other work materials from entering storm drains or watercourses. „ Thoroughly clean up the job site when the repair work is completed. „ When cleaning guardrails or fences follow the appropriate surface cleaning methods (depending on the type of surface) outlined in SC-71 Plaza & Sidewalk Cleaning fact sheet. SC-70 Road and Street Maintenance 6 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ If painting is conducted, follow the painting and paint removal procedures above. „ If graffiti removal is conducted, follow the graffiti removal procedures above. „ If construction takes place, see the Construction Activity BMP Handbook. „ Recycle materials whenever possible. Unpaved Roads and Trails „ Stabilize exposed soil areas to prevent soil from eroding during rain events. This is particularly important on steep slopes. „ For roadside areas with exposed soils, the most cost-effective choice is to vegetate the area, preferably with a mulch or binder that will hold the soils in place while the vegetation is establishing. Native vegetation should be used if possible. „ If vegetation cannot be established immediately, apply temporary erosion control mats/blankets; a comma straw, or gravel as appropriate. „ If sediment is already eroded and mobilized in roadside areas, temporary controls should be installed. These may include: sediment control fences, fabric-covered triangular dikes, gravel-filled burlap bags, biobags, or hay bales staked in place. Non-Stormwater Discharges Field crews should be aware of non-stormwater discharges as part of their ongoing street maintenance efforts. „ Refer to SC-10 Non-Stormwater Discharges „ Identify location, time and estimated quantity of discharges. „ Notify appropriate personnel. Training „ Train employees regarding proper street sweeping operation and street repair and maintenance. „ Instruct employees and subcontractors to ensure that measures to reduce the stormwater impacts of roadway/bridge maintenance are being followed. „ Require engineering staff and/or consulting A/E firms to address stormwater quality in new bridge designs or existing bridge retrofits. „ Use a training log or similar method to document training. „ Train employees on proper spill containment and clean up, and in identifying non- stormwater discharges. Road and Street Maintenance SC-70 January 2003 California Stormwater BMP Handbook 7 of 9 Municipal www.cabmphandbooks.com Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Keep your Spill Prevention Control and countermeasure (SPCC) plan up-to-date, and implement accordingly. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ Densely populated areas or heavily used streets may require parking regulations to clear streets for cleaning. „ No currently available conventional sweeper is effective at removing oil and grease. Mechanical sweepers are not effective at removing finer sediments. „ Limitations may arise in the location of new bridges. The availability and cost of land and other economic and political factors may dictate where the placement of a new bridge will occur. Better design of the bridge to control runoff is required if it is being placed near sensitive waters. Requirements Costs „ The maintenance of local roads and bridges is already a consideration of most community public works or transportation departments. Therefore, the cost of pollutant reducing management practices will involve the training and equipment required to implement these new practices. „ The largest expenditures for street sweeping programs are in staffing and equipment. The capital cost for a conventional street sweeper is between $60,000 and $120,000. Newer technologies might have prices approaching $180,000. The average useful life of a conventional sweeper is about four years, and programs must budget for equipment replacement. Sweeping frequencies will determine equipment life, so programs that sweep more often should expect to have a higher cost of replacement. „ A street sweeping program may require the following. - Sweeper operators, maintenance, supervisory, and administrative personnel are required. - Traffic control officers may be required to enforce parking restrictions. - Skillful design of cleaning routes is required for program to be productive. - Arrangements must be made for disposal of collected wastes. SC-70 Road and Street Maintenance 8 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ If investing in newer technologies, training for operators must be included in operation and maintenance budgets. Costs for public education are small, and mostly deal with the need to obey parking restrictions and litter control. Parking tickets are an effective reminder to obey parking rules, as well as being a source of revenue. Maintenance „ Not applicable Supplemental Information Further Detail of the BMP Street sweeping There are advantages and disadvantages to the two common types of sweepers. The best choice depends on your specific conditions. Many communities find it useful to have a compliment of both types in their fleet. Mechanical Broom Sweepers - More effective at picking up large debris and cleaning wet streets. Less costly to purchase and operate. Create more airborne dust. Vacuum Sweepers - More effective at removing fine particles and associated heavy metals. Ineffective at cleaning wet streets. Noisier than mechanical broom sweepers which may restrict areas or times of operation. May require an advance vehicle to remove large debris. Street Flushers - Not affected by biggest interference to cleaning, parked cars. May remove finer sediments, moving them toward the gutter and stormwater inlets. For this reason, flushing fell out of favor and is now used primarily after sweeping. Flushing may be effective for combined sewer systems. Presently street flushing is not allowed under most NPDES permits. Cross-Media Transfer of Pollutants The California Air Resources Board (ARB) has established state ambient air quality standards including a standard for respirable particulate matter (less than or equal to 10 microns in diameter, symbolized as PM10). In the effort to sweep up finer sediments to remove attached heavy metals, municipalities should be aware that fine dust, that cannot be captured by the sweeping equipment and becomes airborne, could lead to issues of worker and public safety. Bridges Bridges that carry vehicular traffic generate some of the more direct discharges of runoff to surface waters. Bridge scupper drains cause a direct discharge of stormwater into receiving waters and have been shown to carry relatively high concentrations of pollutants. Bridge maintenance also generates wastes that may be either directly deposited to the water below or carried to the receiving water by stormwater. The following steps will help reduce the stormwater impacts of bridge maintenance: „ Site new bridges so that significant adverse impacts to wetlands, sensitive areas, critical habitat, and riparian vegetation are minimized. Road and Street Maintenance SC-70 January 2003 California Stormwater BMP Handbook 9 of 9 Municipal www.cabmphandbooks.com „ Design new bridges to avoid the use of scupper drains and route runoff to land for treatment control. Existing scupper drains should be cleaned on a regular basis to avoid sediment/debris accumulation. „ Reduce the discharge of pollutants to surface waters during maintenance by using suspended traps, vacuums, or booms in the water to capture paint, rust, and paint removing agents. Many of these wastes may be hazardous. Properly dispose of this waste by referring to CA21 (Hazardous Waste Management) in the Construction Handbook. „ Train employees and subcontractors to reduce the discharge of wastes during bridge maintenance. De-icing „ Do not over-apply deicing salt and sand, and routinely calibrate spreaders. „ Near reservoirs, restrict the application of deicing salt and redirect any runoff away from reservoirs. „ Consider using alternative deicing agents (less toxic, biodegradable, etc.). References and Resources Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July. 1998. Orange County Stormwater Program http://www.ocwatersheds.com/stormwater/swp_introduction.asp Oregon Association of Clean Water Agencies. Oregon Municipal Stormwater Toolbox for Maintenance Practices. June 1998. Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. Santa Clara Valley Urban Runoff Pollution Prevention Program. 2001. Fresh Concrete and Mortar Application Best Management Practices for the Construction Industry. June. Santa Clara Valley Urban Runoff Pollution Prevention Program. 2001. Roadwork and Paving Best Management Practices for the Construction Industry. June. United States Environmental Protection Agency (USEPA). 2002. Pollution Prevention/Good Housekeeping for Municipal Operations Roadway and Bridge Maintenance. On-line http://www.epa.gov/npdes/menuofbmps/poll_13.htm Plaza and Sidewalk Cleaning SC-71 January 2003 California Stormwater BMP Handbook 1 of 5 Municipal www.cabmphandbooks.com Description Pollutants on sidewalks and other pedestrian traffic areas and plazas are typically due to littering and vehicle use. This fact sheet describes good housekeeping practices that can be incorporated into the municipality’s existing cleaning and maintenance program. Approach Pollution Prevention „ Use dry cleaning methods whenever practical for surface cleaning activities. „ Use the least toxic materials available (e.g. water based paints, gels or sprays for graffiti removal). Suggested Protocols Surface Cleaning „ Regularly broom (dry) sweep sidewalk, plaza and parking lot areas to minimize cleaning with water. „ Dry cleanup first (sweep, collect, and dispose of debris and trash) when cleaning sidewalks or plazas, then wash with or without soap. „ Block the storm drain or contain runoff when cleaning with water. Discharge wash water to landscaping or collect water and pump to a tank or discharge to sanitary sewer if allowed. (Permission may be required from local sanitation district.) Objectives „ Cover „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-71 Plaza and Sidewalk Cleaning 2 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Block the storm drain or contain runoff when washing parking areas, driveways or drive- throughs. Use absorbents to pick up oil; then dry sweep. Clean with or without soap. Collect water and pump to a tank or discharge to sanitary sewer if allowed. Street Repair and Maintenance. Graffiti Removal „ Avoid graffiti abatement activities during rain events. „ Implement the procedures under Painting and Paint Removal in SC-70 Roads, Streets, and Highway Operation and Maintenance fact sheet when graffiti is removed by painting over. „ Direct runoff from sand blasting and high pressure washing (with no cleaning agents) into a dirt or landscaped area after treating with an appropriate filtering device. „ Plug nearby storm drain inlets and vacuum/pump wash water to the sanitary sewer if authorized to do so if a graffiti abatement method generates wash water containing a cleaning compound (such as high pressure washing with a cleaning compound). Ensure that a non-hazardous cleaning compound is used or dispose as hazardous waste, as appropriate. Surface Removal and Repair „ Schedule surface removal activities for dry weather if possible. „ Avoid creating excess dust when breaking asphalt or concrete. „ Take measures to protect nearby storm drain inlets prior to breaking up asphalt or concrete (e.g. place hay bales or sand bags around inlets). Clean afterwards by sweeping up as much material as possible. „ Designate an area for clean up and proper disposal of excess materials. „ Remove and recycle as much of the broken pavement as possible to avoid contact with rainfall and stormwater runoff. „ When making saw cuts in pavement, use as little water as possible. Cover each storm drain inlet completely with filter fabric during the sawing operation and contain the slurry by placing straw bales, sandbags, or gravel dams around the inlets. After the liquid drains or evaporates, shovel or vacuum the slurry residue from the pavement or gutter and remove from site. „ Always dry sweep first to clean up tracked dirt. Use a street sweeper or vacuum truck. Do not dump vacuumed liquid in storm drains. Once dry sweeping is complete, the area may be hosed down if needed. Wash water should be directed to landscaping or collected and pumped to the sanitary sewer if allowed. Concrete Installation and Repair „ Schedule asphalt and concrete activities for dry weather. Plaza and Sidewalk Cleaning SC-71 January 2003 California Stormwater BMP Handbook 3 of 5 Municipal www.cabmphandbooks.com „ Take measures to protect any nearby storm drain inlets and adjacent watercourses, prior to breaking up asphalt or concrete (e.g. place san bags around inlets or work areas). „ Limit the amount of fresh concrete or cement mortar mixed, mix only what is needed for the job. „ Store concrete materials under cover, away from drainage areas. Secure bags of cement after they are open. Be sure to keep wind-blown cement powder away from streets, gutters, storm drains, rainfall, and runoff. „ Return leftover materials to the transit mixer. Dispose of small amounts of hardened excess concrete, grout, and mortar in the trash. „ Do not wash sweepings from exposed aggregate concrete into the street or storm drain. Collect and return sweepings to aggregate base stockpile, or dispose in the trash. „ Protect applications of fresh concrete from rainfall and runoff until the material has dried. „ Do not allow excess concrete to be dumped onsite, except in designated areas. „ Wash concrete trucks off site or in designated areas on site designed to preclude discharge of wash water to drainage system. Controlling Litter „ Post “No Littering” signs and enforce anti-litter laws. „ Provide litter receptacles in busy, high pedestrian traffic areas of the community, at recreational facilities, and at community events. „ Cover litter receptacles and clean out frequently to prevent leaking/spillage or overflow. „ Clean parking lots on a regular basis with a street sweeper. Training „ Provide regular training to field employees and/or contractors regarding surface cleaning and proper operation of equipment. „ Train employee and contractors in proper techniques for spill containment and cleanup. „ Use a training log or similar method to document training. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. SC-71 Plaza and Sidewalk Cleaning 4 of 5 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Other Considerations „ Limitations related to sweeping activities at large parking facilities may include current sweeper technology to remove oil and grease. „ Surface cleaning activities that require discharges to the local sewering agency will require coordination with the agency. „ Arrangements for disposal of the swept material collected must be made, as well as accurate tracking of the areas swept and the frequency of sweeping. Requirements Costs „ The largest expenditures for sweeping and cleaning of sidewalks, plazas, and parking lots are in staffing and equipment. Sweeping of these areas should be incorporated into street sweeping programs to reduce costs. Maintenance Not applicable Supplemental Information Further Detail of the BMP Community education, such as informing residents about their options for recycling and waste disposal, as well as the consequences of littering, can instill a sense of citizen responsibility and potentially reduce the amount of maintenance required by the municipality. Additional BMPs that should be considered for parking lot areas include: „ Allow sheet runoff to flow into biofilters (vegetated strip and swale) and infiltration devices. „ Utilize sand filters or oleophilic collectors for oily waste in low concentrations. „ Arrange rooftop drains to prevent drainage directly onto paved surfaces. „ Design lot to include semi-permeable hardscape. „ Structural BMPs such as storm drain inlet filters can be very effective in reducing the amount of pollutants discharged from parking facilities during periods of rain. References and Resources Bay Area Stormwater Management Agencies Association (BASMAA). 1996. Pollution From Surface Cleaning Folder http://www.basmaa.org Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July. 1998. Plaza and Sidewalk Cleaning SC-71 January 2003 California Stormwater BMP Handbook 5 of 5 Municipal www.cabmphandbooks.com Oregon Association of Clean Water Agencies. Oregon Municipal Stormwater Toolbox for Maintenance Practices. June 1998. Orange County Stormwater Program http://www.ocwatersheds.com/stormwater/swp_introduction.asp Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. Santa Clara Valley Urban Runoff Pollution Prevention Program. Maintenance Best Management Practices for the Construction Industry. Brochures: Landscaping, Gardening, and Pool; Roadwork and Paving; and Fresh Concrete and Mortar Application. June 2001. San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Plan. 2001. Municipal Activities Model Program Guidance. November. Landscape Maintenance SC-73 January 2003 California Stormwater BMP Handbook 1 of 6 Municipal www.cabmphandbooks.com Description Landscape maintenance activities include vegetation removal; herbicide and insecticide application; fertilizer application; watering; and other gardening and lawn care practices. Vegetation control typically involves a combination of chemical (herbicide) application and mechanical methods. All of these maintenance practices have the potential to contribute pollutants to the storm drain system. The major objectives of this BMP are to minimize the discharge of pesticides, herbicides and fertilizers to the storm drain system and receiving waters; prevent the disposal of landscape waste into the storm drain system by collecting and properly disposing of clippings and cuttings, and educating employees and the public. Approach Pollution Prevention „ Implement an integrated pest management (IPM) program. IPM is a sustainable approach to managing pests by combining biological, cultural, physical, and chemical tools. „ Choose low water using flowers, trees, shrubs, and groundcover. „ Consider alternative landscaping techniques such as naturescaping and xeriscaping. „ Conduct appropriate maintenance (i.e. properly timed fertilizing, weeding, pest control, and pruning) to help preserve the landscapes water efficiency. Objectives „ Contain „ Educate „ Reduce/Minimize „ Product Substitution Targeted Constituents Sediment ; Nutrients ; Trash ; Metals Bacteria Oil and Grease Organics Oxygen Demanding ; SC-73 Landscape Maintenance 2 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Consider grass cycling (grass cycling is the natural recycling of grass by leaving the clippings on the lawn when mowing. Grass clippings decompose quickly and release valuable nutrients back into the lawn). Suggested Protocols Mowing, Trimming, and Weeding „ Whenever possible use mechanical methods of vegetation removal (e.g mowing with tractor- type or push mowers, hand cutting with gas or electric powered weed trimmers) rather than applying herbicides. Use hand weeding where practical. „ Avoid loosening the soil when conducting mech anical or manual weed control, this could lead to erosion. Use mulch or other erosion control measures when soils are exposed. „ Performing mowing at optimal times. Mowing should not be performed if significant rain events are predicted. „ Mulching mowers may be recommended for certain flat areas. Other techniques may be employed to minimize mowing such as selective vegetative planting using low maintenance grasses and shrubs. „ Collect lawn and garden clippings, pruning waste, tree trimmings, and weeds. Chip if necessary, and compost or dispose of at a landfill (see waste management section of this fact sheet). „ Place temporarily stockpiled material away from watercourses, and berm or cover stockpiles to prevent material releases to storm drains. Planting „ Determine existing native vegetation features (location, species, size, function, importance) and consider the feasibility of protecting them. Consider elements such as their effect on drainage and erosion, hardiness, maintenance requirements, and possible conflicts between preserving vegetation and the resulting maintenance needs. „ Retain and/or plant selected native vegetation whose features are determined to be beneficial, where feasible. Native vegetation usually requires less maintenance (e.g., irrigation, fertilizer) than planting new vegetation. „ Consider using low water use groundcovers when planting or replanting. Waste Management „ Compost leaves, sticks, or other collected vegetation or dispose of at a permitted landfill. Do not dispose of collected vegetation into waterways or storm drainage systems. „ Place temporarily stockpiled material away from watercourses and storm drain inlets, and berm or cover stockpiles to prevent material releases to the storm drain system. „ Reduce the use of high nitrogen fertilizers that produce excess growth requiring more frequent mowing or trimming. Landscape Maintenance SC-73 January 2003 California Stormwater BMP Handbook 3 of 6 Municipal www.cabmphandbooks.com „ Avoid landscape wastes in and around storm drain inlets by either using bagging equipment or by manually picking up the material. Irrigation „ Where practical, use automatic timers to minimize runoff. „ Use popup sprinkler heads in areas with a lot of activity or where there is a chance the pipes may be broken. Consider the use of mechanisms that reduce water flow to sprinkler heads if broken. „ Ensure that there is no runoff from the landscaped area(s) if re-claimed water is used for irrigation. „ If bailing of muddy water is required (e.g. when repairing a water line leak), do not put it in the storm drain; pour over landscaped areas. „ Irrigate slowly or pulse irrigate to prevent runoff and then only irrigate as much as is needed. „ Apply water at rates that do not exceed the infiltration rate of the soil. Fertilizer and Pesticide Management „ Utilize a comprehensive management system that incorporates integrated pest management (IPM) techniques. There are many methods and types of IPM, including the following: - Mulching can be used to prevent weeds where turf is absent, fencing installed to keep rodents out, and netting used to keep birds and insects away from leaves and fruit. - Visible insects can be removed by hand (with gloves or tweezers) and placed in soapy water or vegetable oil. Alternatively, insects can be sprayed off the plant with water or in some cases vacuumed off of larger plants. - Store-bought traps, such as species-specific, pheromone-based traps or colored sticky cards, can be used. - Slugs can be trapped in small cups filled with beer that are set in the ground so the slugs can get in easily. - In cases where microscopic parasites, such as bacteria and fungi, are causing damage to plants, the affected plant material can be removed and disposed of (pruning equipment should be disinfected with bleach to prevent spreading the disease organism). - Small mammals and birds can be excluded using fences, netting, tree trunk guards. - Beneficial organisms, such as bats, birds, green lacewings, ladybugs, praying mantis, ground beetles, parasitic nematodes, trichogramma wasps, seed head weevils, and spiders that prey on detrimental pest species can be promoted. „ Follow all federal, state, and local laws and regulations governing the use, storage, and disposal of fertilizers and pesticides and training of applicators and pest control advisors. SC-73 Landscape Maintenance 4 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Use pesticides only if there is an actual pest problem (not on a regular preventative schedule). „ Do not use pesticides if rain is expected. Apply pesticides only when wind speeds are low (less than 5 mph). „ Do not mix or prepare pesticides for application near storm drains. „ Prepare the minimum amount of pesticide needed for the job and use the lowest rate that will effectively control the pest. „ Employ techniques to minimize off-target application (e.g. spray drift) of pesticides, including consideration of alternative application techniques. „ Fertilizers should be worked into the soil rather than dumped or broadcast onto the surface. „ Calibrate fertilizer and pesticide application equipment to avoid excessive application. „ Periodically test soils for determining proper fertilizer use. „ Sweep pavement and sidewalk if fertilizer is spilled on these surfaces before applying irrigation water. „ Purchase only the amount of pesticide that you can reasonably use in a given time period (month or year depending on the product). „ Triple rinse containers, and use rinse water as product. Dispose of unused pesticide as hazardous waste. „ Dispose of empty pesticide containers according to the instructions on the container label. Inspection „ Inspect irrigation system periodically to ensure that the right amount of water is being applied and that excessive runoff is not occurring. Minimize excess watering, and repair leaks in the irrigation system as soon as they are observed. „ Inspect pesticide/fertilizer equipment and transportation vehicles daily. Training „ Educate and train employees on use of pesticides and in pesticide application techniques to prevent pollution. Pesticide application must be under the supervision of a California qualified pesticide applicator. „ Train/encourage municipal maintenance crews to use IPM techniques for managing public green areas. „ Annually train employees within departments responsible for pesticide application on the appropriate portions of the agency’s IPM Policy, SOPs, and BMPs, and the latest IPM techniques. Landscape Maintenance SC-73 January 2003 California Stormwater BMP Handbook 5 of 6 Municipal www.cabmphandbooks.com „ Employees who are not authorized and trained to apply pesticides should be periodically (at least annually) informed that they cannot use over-the-counter pesticides in or around the workplace. „ Use a training log or similar method to document training. Spill Response and Prevention „ Refer to SC-11, Spill Prevention, Control & Cleanup „ Have spill cleanup materials readily available and in a know in location „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ The Federal Pesticide, Fungicide, and Rodenticide Act and California Title 3, Division 6, Pesticides and Pest Control Operations place strict controls over pesticide application and handling and specify training, annual refresher, and testing requirements. The regulations generally cover: a list of approved pesticides and selected uses, updated regularly; general application information; equipment use and maintenance procedures; and record keeping. The California Department of Pesticide Regulations and the County Agricultural Commission coordinate and maintain the licensing and certification programs. All public agency employees who apply pesticides and herbicides in “agricultural use” areas such as parks, golf courses, rights-of-way and recreation areas should be properly certified in accordance with state regulations. Contracts for landscape maintenance should include similar requirements. „ All employees who handle pesticides should be familiar with the most recent material safety data sheet (MSDS) files. „ Municipalities do not have the authority to regulate the use of pesticides by school districts, however the California Healthy Schools Act of 2000 (AB 2260) has imposed requirements on California school districts regarding pesticide use in schools. Posting of notification prior to the application of pesticides is now required, and IPM is stated as the preferred approach to pest management in schools. Requirements Costs Additional training of municipal employees will be required to address IPM techniques and BMPs. IPM methods will likely increase labor cost for pest control which may be offset by lower chemical costs. Maintenance Not applicable SC-73 Landscape Maintenance 6 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Supplemental Information Further Detail of the BMP Waste Management Composting is one of the better disposal alternatives if locally available. Most municipalities either have or are planning yard waste composting facilities as a means of reducing the amount of waste going to the landfill. Lawn clippings from municipal maintenance programs as well as private sources would probably be compatible with most composting facilities Contractors and Other Pesticide Users Municipal agencies should develop and implement a process to ensure that any contractor employed to conduct pest control and pesticide application on municipal property engages in pest control methods consistent with the IPM Policy adopted by the agency. Specifically, municipalities should require contractors to follow the agency’s IPM policy, SOPs, and BMPs; provide evidence to the agency of having received training on current IPM techniques when feasible; provide documentation of pesticide use on agency property to the agency in a timely manner. References and Resources King County Stormwater Pollution Control Manual. Best Management Practices for Businesses. 1995. King County Surface Water Management. July. On-line: http://dnr.metrokc.gov/wlr/dss/spcm.htm Los Angeles County Stormwater Quality Model Programs. Public Agency Activities http://ladpw.org/wmd/npdes/model_links.cfm Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July. 1998. Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. United States Environmental Protection Agency (USEPA). 2002. Pollution Prevention/Good Housekeeping for Municipal Operations Landscaping and Lawn Care. Office of Water. Office of Wastewater Management. On-line: http://www.epa.gov/npdes/menuofbmps/poll_8.htm Drainage System Maintenance SC-74 January 2003 California Stormwater BMP Handbook 1 of 9 Municipal www.cabmphandbooks.com Description As a consequence of its function, the stormwater conveyance system collects and transports urban runoff that may contain certain pollutants. Maintaining catch basins, stormwater inlets, and other stormwater conveyance structures on a regular basis will remove pollutants, prevent clogging of the downstream conveyance system, restore catch basins’ sediment trapping capacity, and ensure the system functions properly hydraulically to avoid flooding. Approach Suggested Protocols Catch Basins/Inlet Structures „ Municipal staff should regularly inspect facilities to ensure the following: - Immediate repair of any deterioration threatening structural integrity. - Cleaning before the sump is 40% full. Catch basins should be cleaned as frequently as needed to meet this standard. - Stenciling of catch basins and inlets (see SC-75 Waste Handling and Disposal). „ Clean catch basins, storm drain inlets, and other conveyance structures in high pollutant load areas just before the wet season to remove sediments and debris accumulated during the summer. Objectives „ Contain „ Educate „ Reduce/Minimize Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; Photo Credit: Geoff Brosseau SC-74 Drainage System Maintenance 2 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Conduct inspections more frequently during the wet season for problem areas where sediment or trash accumulates more often. Clean and repair as needed. „ Keep accurate logs of the number of catch basins cleaned. „ Record the amount of waste collected. „ Store wastes collected from cleaning activities of the drainage system in appropriate containers or temporary storage sites in a manner that prevents discharge to the storm drain. „ Dewater the wastes with outflow into the sanitary sewer if permitted. Water should be treated with an appropriate filtering device prior to discharge to the sanitary sewer. If discharge to the sanitary sewer is not allowed, water should be pumped or vacuumed to a tank and properly disposed of. Do not dewater near a storm drain or stream. „ Except for small communities with relatively few catch basins that may be cleaned manually, most municipalities will require mechanical cleaners such as eductors, vacuums, or bucket loaders. Storm Drain Conveyance System „ Locate reaches of storm drain with deposit problems and develop a flushing schedule that keeps the pipe clear of excessive buildup. „ Collect flushed effluent and pump to the sanitary sewer for treatment. Pump Stations „ Clean all storm drain pump stations prior to the wet season to remove silt and trash. „ Do not allow discharge from cleaning a storm drain pump station or other facility to reach the storm drain system. „ Conduct quarterly routine maintenance at each pump station. „ Inspect, clean, and repair as necessary all outlet structures prior to the wet season. „ Sample collected sediments to determine if landfill disposal is possible, or illegal discharges in the watershed are occurring. Open Channel „ Consider modification of storm channel characteristics to improve channel hydraulics, to increase pollutant removals, and to enhance channel/creek aesthetic and habitat value. „ Conduct channel modification/improvement in accordance with existing laws. Any person, government agency, or public utility proposing an activity that will change the natural (emphasis added) state of any river, stream, or lake in California, must enter into a steam or Lake Alteration Agreement with the Department of Fish and Game. The developer-applicant should also contact local governments (city, county, special districts), other state agencies Drainage System Maintenance SC-74 January 2003 California Stormwater BMP Handbook 3 of 9 Municipal www.cabmphandbooks.com (SWRCB, RWQCB, Department of Forestry, Department of Water Resources), and Federal Corps of Engineers and USFWS Illicit Connections and Discharges „ During routine maintenance of conveyance system and drainage structures field staff should look for evidence of illegal discharges or illicit connections: - Is there evidence of spills such as paints, discoloring, etc. - Are there any odors associated with the drainage system - Record locations of apparent illegal discharges/illicit connections - Track flows back to potential dischargers and conduct aboveground inspections. This can be done through visual inspection of up gradient manholes or alternate techniques including zinc chloride smoke testing, fluorometric dye testing, physical inspection testing, or television camera inspection. - Once the origin of flow is established, require illicit discharger to eliminate the discharge. „ Stencil storm drains, where applicable, to prevent illegal disposal of pollutants. Storm drain inlets should have messages such as “Dump No Waste Drains to Stream” stenciled next to them to warn against ignorant or intentional dumping of pollutants into the storm drainage system. „ Refer to fact sheet SC-10 Non-Stormwater Discharges. Illegal Dumping „ Regularly inspect and clean up hot spots and other storm drainage areas where illegal dumping and disposal occurs. „ Establish a system for tracking incidents. The system should be designed to identify the following: - Illegal dumping hot spots - Types and quantities (in some cases) of wastes - Patterns in time of occurrence (time of day/night, month, or year) - Mode of dumping (abandoned containers, “midnight dumping” from moving vehicles, direct dumping of materials, accidents/spills) - Responsible parties „ Post “No Dumping” signs in problem areas with a phone number for reporting dumping and disposal. Signs should also indicate fines and penalties for illegal dumping. „ Refer to fact sheet SC-10 Non-Stormwater Discharges. SC-74 Drainage System Maintenance 4 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ The State Department of Fish and Game has a hotline for reporting violations called Cal TIP (1-800-952-5400). The phone number may be used to report any violation of a Fish and Game code (illegal dumping, poaching, etc.). „ The California Department of Toxic Substances Control’s Waste Alert Hotline, 1-800- 69TOXIC, can be used to report hazardous waste violations. Training „ Train crews in proper maintenance activities, including record keeping and disposal. „ Only properly trained individuals are allowed to handle hazardous materials/wastes. „ Train municipal employees from all departments (public works, utilities, street cleaning, parks and recreation, industrial waste inspection, hazardous waste inspection, sewer maintenance) to recognize and report illegal dumping. „ Train municipal employees and educate businesses, contractors, and the general public in proper and consistent methods for disposal. „ Train municipal staff regarding non-stormwater discharges (See SC-10 Non-Stormwater Discharges). Spill Response and Prevention „ Refer to SC-11, Prevention, Control & Cleanup „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ Cleanup activities may create a slight disturbance for local aquatic species. Access to items and material on private property may be limited. Trade-offs may exist between channel hydraulics and water quality/riparian habitat. If storm channels or basins are recognized as wetlands, many activities, including maintenance, may be subject to regulation and permitting. „ Storm drain flushing is most effective in small diameter pipes (36-inch diameter pipe or less, depending on water supply and sediment collection capacity). Other considerations associated with storm drain flushing may include the availability of a water source, finding a downstream area to collect sediments, liquid/sediment disposal, and disposal of flushed effluent to sanitary sewer may be prohibited in some areas. „ Regulations may include adoption of substantial penalties for illegal dumping and disposal. „ Municipal codes should include sections prohibiting the discharge of soil, debris, refuse, hazardous wastes, and other pollutants into the storm drain system. „ Private property access rights may be needed to track illegal discharges up gradient. Drainage System Maintenance SC-74 January 2003 California Stormwater BMP Handbook 5 of 9 Municipal www.cabmphandbooks.com „ Requirements of municipal ordinance authority for suspected source verification testing for illicit connections necessary for guaranteed rights of entry. Requirements Costs „ An aggressive catch basin cleaning program could require a significant capital and O&M budget. A careful study of cleaning effectiveness should be undertaken before increased cleaning is implemented. Catch basin cleaning costs are less expensive if vacuum street sweepers are available; cleaning catch basins manually can cost approximately twice as much as cleaning the basins with a vacuum attached to a sweeper. „ Methods used for illicit connection detection (smoke testing, dye testing, visual inspection, and flow monitoring) can be costly and time-consuming. Site-specific factors, such as the level of impervious area, the density and ages of buildings, and type of land use will determine the level of investigation necessary. Encouraging reporting of illicit discharges by employees can offset costs by saving expense on inspectors and directing resources more efficiently. Some programs have used funds available from “environmental fees” or special assessment districts to fund their illicit connection elimination programs. Maintenance „ Two-person teams may be required to clean catch basins with vactor trucks. „ Identifying illicit discharges requires teams of at least two people (volunteers can be used), plus administrative personnel, depending on the complexity of the storm sewer system. „ Arrangements must be made for proper disposal of collected wastes. „ Requires technical staff to detect and investigate illegal dumping violations, and to coordinate public education. Supplemental Information Further Detail of the BMP Storm Drain flushing Sanitary sewer flushing is a common maintenance activity used to improve pipe hydraulics and to remove pollutants in sanitary sewer systems. The same principles that make sanitary sewer flushing effective can be used to flush storm drains. Flushing may be designed to hydraulically convey accumulated material to strategic locations, such as to an open channel, to another point where flushing will be initiated, or over to the sanitary sewer and on to the treatment facilities, thus preventing re-suspension and overflow of a portion of the solids during storm events. Flushing prevents “plug flow” discharges of concentrated pollutant loadings and sediments. The deposits can hinder the designed conveyance capacity of the storm drain system and potentially cause backwater conditions in severe cases of clogging. Storm drain flushing usually takes place along segments of pipe with grades that are too flat to maintain adequate velocity to keep particles in suspension. An upstream manhole is selected to place an inflatable device that temporarily plugs the pipe. Further upstream, water is pumped into the line to create a flushing wave. When the upstream reach of pipe is sufficiently full to SC-74 Drainage System Maintenance 6 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com cause a flushing wave, the inflated device is rapidly deflated with the assistance of a vacuum pump, releasing the backed up water and resulting in the cleaning of the storm drain segment. To further reduce the impacts of stormwater pollution, a second inflatable device, placed well downstream, may be used to re-collect the water after the force of the flushing wave has dissipated. A pump may then be used to transfer the water and accumulated material to the sanitary sewer for treatment. In some cases, an interceptor structure may be more practical or required to re-collect the flushed waters. It has been found that cleansing efficiency of periodic flush waves is dependent upon flush volume, flush discharge rate, sewer slope, sewer length, sewer flow rate, sewer diameter, and population density. As a rule of thumb, the length of line to be flushed should not exceed 700 feet. At this maximum recommended length, the percent removal efficiency ranges between 65- 75 percent for organics and 55-65 percent for dry weather grit/inorganic material. The percent removal efficiency drops rapidly beyond that. Water is commonly supplied by a water truck, but fire hydrants can also supply water. To make the best use of water, it is recommended that reclaimed water be used or that fire hydrant line flushing coincide with storm drain flushing. Flow Management Flow management has been one of the principal motivations for designing urban stream corridors in the past. Such needs may or may not be compatible with the stormwater quality goals in the stream corridor. Downstream flood peaks can be suppressed by reducing through flow velocity. This can be accomplished by reducing gradient with grade control structures or increasing roughness with boulders, dense vegetation, or complex banks forms. Reducing velocity correspondingly increases flood height, so all such measures have a natural association with floodplain open space. Flood elevations laterally adjacent to the stream can be lowered by increasing through flow velocity. However, increasing velocity increases flooding downstream and inherently conflicts with channel stability and human safety. Where topography permits, another way to lower flood elevation is to lower the level of the floodway with drop structures into a large but subtly excavated bowl where flood flows we allowed to spread out. Stream Corridor Planning Urban streams receive and convey stormwater flows from developed or developing watersheds. Planning of stream corridors thus interacts with urban stormwater management programs. If local programs are intended to control or protect downstream environments by managing flows delivered to the channels, then it is logical that such programs should be supplemented by management of the materials, forms, and uses of the downstream riparian corridor. Any proposal for steam alteration or management should be investigated for its potential flow and stability effects on upstream, downstream, and laterally adjacent areas. The timing and rate of flow from various tributaries can combine in complex ways to alter flood hazards. Each section of channel is unique, influenced by its own distribution of roughness elements, management activities, and stream responses. Drainage System Maintenance SC-74 January 2003 California Stormwater BMP Handbook 7 of 9 Municipal www.cabmphandbooks.com Flexibility to adapt to stream features and behaviors as they evolve must be included in stream reclamation planning. The amenity and ecology of streams may be enhanced through the landscape design options of 1) corridor reservation, 2) bank treatment, 3) geomorphic restoration, and 4) grade control. Corridor reservation - Reserving stream corridors and valleys to accommodate natural stream meandering, aggradation, degradation, and over bank flows allows streams to find their own form and generate less ongoing erosion. In California, open stream corridors in recent urban developments have produced recreational open space, irrigation of streamside plantings, and the aesthetic amenity of flowing water. Bank treatment - The use of armoring, vegetative cover, and flow deflection may be used to influence a channel’s form, stability, and biotic habitat. To prevent bank erosion, armoring can be done with rigid construction materials, such as concrete, masonry, wood planks and logs, riprap, and gabions. Concrete linings have been criticized because of their lack of provision of biotic habitat. In contrast, riprap and gabions make relatively porous and flexible linings. Boulders, placed in the bed reduce velocity and erosive power. Riparian vegetation can stabilize the banks of streams that are at or near a condition of equilibrium. Binding networks of roots increase bank shear strength. During flood flows, resilient vegetation is forced into erosion-inhibiting mats. The roughness of vegetation leads to lower velocity, further reducing erosive effects. Structural flow deflection can protect banks from erosion or alter fish habitat. By concentrating flow, a deflector causes a pool to be scoured in the bed. Geomorphic restoration – Restoration refers to alteration of disturbed streams so their form and behavior emulate those of undisturbed streams. Natural meanders are retained, with grading to gentle slopes on the inside of curves to allow point bars and riffle-pool sequences to develop. Trees are retained to provide scenic quality, biotic productivity, and roots for bank stabilization, supplemented by plantings where necessary. A restorative approach can be successful where the stream is already approaching equilibrium. However, if upstream urbanization continues new flow regimes will be generated that could disrupt the equilibrium of the treated system. Grade Control - A grade control structure is a level shelf of a permanent material, such as stone, masonry, or concrete, over which stream water flows. A grade control structure is called a sill, weir, or drop structure, depending on the relation of its invert elevation to upstream and downstream channels. A sill is installed at the preexisting channel bed elevation to prevent upstream migration of nick points. It establishes a firm base level below which the upstream channel can not erode. A weir or check dam is installed with invert above the preexisting bed elevation. A weir raises the local base level of the stream and causes aggradation upstream. The gradient, velocity, and erosive potential of the stream channel are reduced. A drop structure lowers the downstream invert below its preexisting elevation, reducing downstream gradient and velocity. Weirs and drop structure control erosion by dissipating energy and reducing slope velocity. SC-74 Drainage System Maintenance 8 of 9 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com When carefully applied, grade control structures can be highly versatile in establishing human and environmental benefits in stabilized channels. To be successful, application of grade control structures should be guided by analysis of the stream system both upstream and downstream from the area to he reclaimed. Examples The California Department of Water Resources began the Urban Stream Restoration Program in 1985. The program provides grant funds to municipalities and community groups to implement stream restoration projects. The projects reduce damages from streambank aid watershed instability arid floods while restoring streams’ aesthetic, recreational, and fish and wildlife values. In Buena Vista Park, upper floodway slopes are gentle and grassed to achieve continuity of usable park land across the channel of small boulders at the base of the slopes. The San Diego River is a large, vegetative lined channel, which was planted in a variety of species to support riparian wildlife while stabilizing the steep banks of the floodway. References and Resources Ferguson, B.K. 1991. Urban Stream Reclamation, p. 324-322, Journal of Soil and Water Conservation. Los Angeles County Stormwater Quality. Public Agency Activities Model Program. On-line: http://ladpw.org/wmd/npdes/public_TC.cfm Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July. 1998. Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. San Diego Stormwater Co-permittees Jurisdictional Urban Runoff Management Program (URMP) Municipal Activities Model Program Guidance. 2001. Project Clean Water. November. United States Environmental Protection Agency (USEPA). 1999. Stormwater Management Fact Sheet Non-stormwater Discharges to Storm Sewers. EPA 832-F-99-022. Office of Water, Washington, D.C. September. United States Environmental Protection Agency (USEPA). 1999. Stormwater O&M Fact Sheet Catch Basin Cleaning. EPA 832-F-99-011. Office of Water, Washington, D.C. September. Drainage System Maintenance SC-74 January 2003 California Stormwater BMP Handbook 9 of 9 Municipal www.cabmphandbooks.com United States Environmental Protection Agency (USEPA). 2002. Pollution Prevention/Good Housekeeping for Municipal Operations Illegal Dumping Control. On line: http://www.epa.gov/npdes/menuofbmps/poll_7.htm United States Environmental Protection Agency (USEPA). 2002. Pollution Prevention/Good Housekeeping for Municipal Operations Storm Drain System Cleaning. On line: http://www.epa.gov/npdes/menuofbmps/poll_16.htm Waste Handling and Disposal SC-75 January 2003 California Stormwater BMP Handbook 1 of 4 Municipal www.cabmphandbooks.com Description It is important to control litter to eliminate trash and other materials in stormwater runoff. Waste reduction is a major component of waste management and should be encouraged through training and public outreach. Management of waste once it is collected may involve reuse, recycling, or proper disposal. Approach Pollution Prevention „ Reuse products when possible. „ Encourage recycling programs with recycling bins, used oil collection, etc. Suggested Protocols Solid Waste Collection „ Implement procedures, where applicable, to collect, transport, and dispose of solid waste at appropriate disposal facilities in accordance with applicable federal, state, and local laws and regulations. „ Include properly designed trash storage areas. If feasible provide cover over trash storage areas. „ Regularly inspect solid waste containers for structural damage. Repair or replace damaged containers as necessary. Objectives „ Cover „ Contain „ Educate „ Reduce/Reuse Targeted Constituents Sediment ; Nutrients ; Trash ; Metals ; Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-75 Waste Handling and Disposal 2 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Secure solid waste containers; containers must be closed tightly when not in use. „ Do not fill waste containers with washout water or any other liquid. „ Ensure that only appropriate solid wastes are added to the solid waste container. Certain wastes such as hazardous wastes, appliances, fluorescent lamps, pesticides, etc. may not be disposed of in solid waste containers (see chemical/ hazardous waste collection section below). „ Do not mix wastes; this can cause chemical reactions, make recycling impossible, and complicate disposal. „ Refer to SC-34 Waste Handling and Disposal for more information regarding solid waste facilities. Waste Reduction and Recycling „ Recycle wastes whenever possible. Many types of waste can be recycled, recycling options for each waste type are limited. All gasoline, antifreeze, waste oil, and lead-acid batteries can be recycled. Latex and oil-based paint can be reused, as well as recycled. Materials that cannot be reused or recycled should either be incinerated or disposed of at a properly permitted landfill. „ Recycling is always preferable to disposal of unwanted materials. „ Recycling bins for glass, metal, newspaper, plastic bottles and other recyclable household solid wastes should be provided at public facilities and/or for residential curbside collection. Controlling Litter „ Post “No Littering” signs and enforce anti-litter laws. „ Provide litter receptacles in busy, high pedestrian traffic areas of the community, at recreational facilities, and at community events. „ Clean out and cover litter receptacles frequently to prevent spillage. Illegal Dumping Substances illegally dumped on streets and into the storm drain system and creeks include paints, used oil and other automotive fluids, construction debris, chemicals, fresh concrete, leaves, grass clipping, and pet wastes. „ Post “No Dumping” signs with a phone number for reporting dumping and disposal. Signs should also indicate fines and penalties for illegal dumping. „ Landscaping and beautification efforts of hot spots might also discourage future dumping. „ See SC-74 Drainage System Maintenance, and SC-10 Non-Stormwater Discharges. Waste Handling and Disposal SC-75 January 2003 California Stormwater BMP Handbook 3 of 4 Municipal www.cabmphandbooks.com Requirements Costs „ The costs for a solid waste source control program vary depending on the type of method. The cost of a community education program or a plan to increase the number of trash receptacles can be very minimal. Costs for structural controls such as trash racks, bar screens, and silt traps can be quite costly ranging from $250,000 to $900,000. „ A collection facility or curbside collection for used oil may result in significant costs. Commercial locations (automobile service stations, quick oil change centers, etc.) as collection points eliminate hauling and recycling costs. „ Collection and disposal of hazardous waste can be very expensive and requires trained operators; laboratory and detection equipment; and extensive record keeping including dates, types, and quantities. „ Use of volunteer work forces can lower storm drain stenciling program costs. Stenciling kits require procurement of durable/disposable items. The stenciling program can aid in the cataloging of the storm drain system. One municipality from the state of Washington has estimated that stenciling kits cost approximately $50 each. Stencils may cost about $8 each including the die cost on an order of 1,000. Re-orders cost about $1/stencil. Stencil designs may be available from other communities. Stencil kits should be provided on a loan basis to volunteer groups free of charge with the understanding that kit remnants are to be returned. Maintenance „ The primary staff demand for stenciling programs is for program setup to provide marketing and training. Ongoing/follow-up staff time is minimal because of volunteer services. „ Staffing requirements are minimal for oil recycling programs if collection/recycling is contracted out to a used oil hauler/recycler or required at commercial locations. „ Staff requirements for maintaining good housekeeping BMPs at waste handling sites is minimal. Supplemental Information Further Detail of the BMP Waste Reduction An approach to reduce stormwater pollution from waste handling and disposal is to assess activities and reduce waste generation. The assessment is designed to find situations where waste can be eliminated or reduced and emissions and environmental damage can be minimized. The assessment involves collecting process specific information, setting pollution prevention targets, and developing, screening and selecting waste reduction options for further study. Starting a waste reduction program is economically beneficial because of reduced raw material purchases and lower waste disposal fees. SC-75 Waste Handling and Disposal 4 of 4 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com References and Resources Best Management Practices Program for Pollution Prevention, City and County of San Francisco, Uribe & Associates, Oakland, California, 1990. Harvard University. 2002. Solid Waste Container Best Management Practices – Fact Sheet On- Line Resources – Environmental Health and Safety. Model Urban Runoff Program: A How-To-Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Commission, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July 1998. (Revised February 2002 by the California Coastal Commission). Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp. Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. Water & Sewer Utility Maintenance SC-76 January 2003 California Stormwater BMP Handbook 1 of 8 Municipal www.cabmphandbooks.com Description Although the operation and maintenance of public utilities are not considered chronic sources of stormwater pollution, some activities and accidents can result in the discharge of pollutants that can pose a threat to both human health and the quality of receiving waters if they enter the storm drain system. Sewage incident response and investigation may involve a coordinated effort between staff from a number of different departments/agencies. Cities that do not provide maintenance of water and sewer utilities must coordinate with the contracting agency responsible for these activities and ensure that these model procedures are followed. Approach Pollution Prevention Inspect potential non-stormwater discharge flow paths and clear/cleanup any debris or pollutants found (i.e. remove trash, leaves, sediment, and wipe up liquids, including oil spills). Suggested Protocols Water Line Maintenance and Cleaning Procedures can be employed to reduce pollutants from discharges associated with water utility operation and maintenance activities. Planned discharges may include fire hydrant testing, flushing water supply mains after new construction, flushing lines due to complaints of taste and odor, dewatering mains for maintenance work. Unplanned discharges from treated, recycled water, raw water, and groundwater systems operation and maintenance activities can occur from water main Objectives „ Contain „ Educate „ Reduce/Minimize Targeted Constituents Sediment ; Nutrients ; Trash Metals Bacteria ; Oil and Grease ; Organics ; Oxygen Demanding ; SC-76 Water & Sewer Utility Maintenance 2 of 8 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com breaks, sheared fire hydrants, equipment malfunction, and operator error. Planned discharges „ Identify a suitable discharge option in the following order of preference: - Apply to the land. - Reuse water for dust suppression, irrigation, or construction compaction. - Discharge to a sanitary sewer system with approval. - Discharge to the storm drain system using applicable pollution control measures. (Only available to clean water discharges such as water main/ water storage tank/water hydrant flushing). „ If water is discharged to a storm drain, control measures must be put in place to control potential pollutants (i.e. sediment, chlorine, etc.). Examples of some storm drain protection options include: - Silt fence – appropriate where the inlet drains a relatively flat area. - Gravel and wire mesh sediment filter – Appropriate where concentrated flows are expected. - Wooden weir and fabric – use at curb inlets where a compact installation is desired. „ Prior to discharge, inspect discharge flow path and clear/cleanup any debris or pollutants found (i.e. remove trash, leaves, sediment, and wipe up liquids, including oil spills). „ General Design considerations for inlet protection devices include the following: - The device should be constructed such that cleaning and disposal of trapped sediment is made easy, while minimizing interference with discharge activities. - Devices should be constructed so that any standing water resulting from the discharge will not cause excessive inconvenience or flooding/damage to adjacent land or structures. „ The effectiveness of control devices must be monitored during the discharge period and any necessary repairs or modifications made. Unplanned Discharges „ Stop the discharge as quickly as possible. „ Inspect flow path of the discharged water: - Identify erodible areas which may need to be repaired or protected during subsequent repairs or corrective actions Water & Sewer Utility Maintenance SC-76 January 2003 California Stormwater BMP Handbook 3 of 8 Municipal www.cabmphandbooks.com - Identify the potential for pollutants to be washed into the waterway „ If repairs or corrective action will cause additional discharges of water, select the appropriate procedures for erosion control, chlorine residual, turbidity, and chemical additives. Prevent potential pollutants from entering the flow path. Sanitary Sewer Maintenance Applicable to municipalities who own and operated a sewage collection system. Facilities that are covered under this program include sanitary sewer pipes and pump stations owned and operated by a municipality. The owner of the sanitary sewer facilities is the entity responsible for carrying out this prevention and response program. „ Clean sewer lines on a regular basis to remove grease, grit, and other debris that may lead to sewer backups. „ Establish routine maintenance program. Cleaning should be conducted at an established minimum frequency and more frequently for problem areas such as restaurants that are identified „ Cleaning activities may require removal of tree roots and other identified obstructions. „ During routine maintenance and inspection note the condition of sanitary sewer structures and identify areas that need repair or maintenance. Items to note may include the following: - Cracked/deteriorating pipes - Leaking joints/seals at manhole - Frequent line plugs - Line generally flows at or near capacity - Suspected infiltration or exfiltration. „ Prioritize repairs based on the nature and severity of the problem. Immediate clearing of blockage or repair is required where an overflow is currently occurring or for urgent problems that may cause an imminent overflow (e.g. pump station failures, sewer line ruptures, sewer line blockages). These repairs may be temporary until scheduled or capital improvements can be completed. „ Review previous sewer maintenance records to help identify “hot spots” or areas with frequent maintenance problems and locations of potential system failure. Spills and Overflows „ Identify and track sanitary sewer discharges. Identify dry weather infiltration and inflow first. Wet weather overflow connections are very difficult to locate. SC-76 Water & Sewer Utility Maintenance 4 of 8 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com „ Locate wet weather overflows and leaking sanitary sewers using conventional source identification techniques such as monitoring and field screening. Techniques used to identify other illicit connection sources can also be used for sewer system evaluation surveys (see SC74 Drainage System Operation and Maintenance). „ Implement community awareness programs for monitoring sanitary sewer wet weather overflows. A citizen’s hotline for reporting observed overflow conditions should be established to supplement field screening efforts. „ Establish lead department/agency responsible for spill response and containment. Provide coordination within departments. „ When a spill, leak, and/or overflow occurs and when disinfecting a sewage contaminated area, take every effort to ensure that the sewage, disinfectant and/or sewage treated with the disinfectant is not discharged to the storm drain system or receiving waters. Methods may include: - Blocking storm drain inlets and catch basins - Containing and diverting sewage and disinfectant away from open channels and other storm drain fixtures (using sandbags, inflatable dams, etc.) - Removing the material with vacuum equipment „ Record required information at the spill site. „ Perform field tests as necessary to determine the source of the spill. „ Develop notification procedures regarding spill reporting. Septic Systems „ Ensure that homeowners, installers, and inspectors are educated in proper maintenance of septic systems. This may require coordination with staff from other departments. Outreach to homeowners should include inspection reminders informing then that inspection and perhaps maintenance is due for their systems. Recommend that the system be inspected annually and pumped-out regularly. „ Programs which seek to address failing septic systems should consider using field screening to pinpoint areas where more detailed onsite inspection surveys are warranted. Training „ Conduct annual training of water utility personnel and service contractors. (field screening, sampling, smoke/dye testing, TV inspection). „ OSHA-required Health and Safety Training 29 CFR 1910.120 plus annual Refresher Training (as needed). „ OSHA Confined Space Entry training (Cal-OSHA Confined Space, Title 8 and federal OSHA 29 CFR 1910.146). Water & Sewer Utility Maintenance SC-76 January 2003 California Stormwater BMP Handbook 5 of 8 Municipal www.cabmphandbooks.com Spill Response and Prevention „ See previous section regarding spills and overflows. „ Refer to SC-11, Spill Prevention, Control & Cleanup. „ Have spill cleanup materials readily available and in a known location. „ Cleanup spills immediately and use dry methods if possible. „ Properly dispose of spill cleanup material. Other Considerations „ Enact ordinance granting “right-of-entry” to locate potentially responsible parties for sewer overflows. „ Reliance on individual onsite inspection to detect failed septic systems can be a major limitation. The individual onsite inspection is very labor-intensive and requires access to private property to pinpoint the exact location of the failing system. „ A significant limitation to correcting failing septic systems is the lack of techniques available for detecting individual failed septic systems. Requirements Costs „ Departmental cooperation recommended for sharing or borrowing staff resources and equipment from municipal wastewater department. „ Infiltration, inflow, and wet weather overflows from sanitary sewers are very labor and equipment intensive to locate. „ The costs associated with detecting and correcting septic system failures are subject to a number of factors, including availability of trained personnel, cost of materials, and the level of follow-up required to fix the system problems. Maintenance „ Minimum 2-person teams to perform field screening and associated sampling. „ Larger teams required for implementing other techniques (i.e. zinc chloride smoke testing, fluorometric dye testing, television camera inspection and physical inspection with confined space entry) to identify sewer system leaks. „ Program coordination required for handling emergencies, record keeping, etc. „ Many of the problems associated with improper use of septic systems may be attributed to lack of user knowledge on operation and maintenance. Educational materials for homeowners and training courses for installers and inspectors can reduce the incidence of pollution from these widespread and commonly used pollution control devices. SC-76 Water & Sewer Utility Maintenance 6 of 8 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Supplemental Information Further Detail of the BMP Onsite Sewage Disposal Systems New onsite sewage disposal systems should be designed, located, and installed away from open waterbodies and sensitive resources such as wetlands and floodplains. A protective separation between the OSDS and groundwater should also be established. OSDSs should be operated and maintained to prevent surface water discharges and reduce pollutant loadings to groundwater. Inspection of OSDSs should occur regularly and repairs made immediately. New or replacement plumbing fixtures should be of the high efficiency type. Typical Sanitary Sewer Problems „ Old and deteriorated main and lateral pipes - Sewers range in age from 30 to 100 years with an average age of 50 years. „ Cracked sewer pipes - Existing sewers are mostly clay pipes which can crack as they deteriorate with age and also by earth movement. „ Misaligned and open pipe joints - Most of the mortar used to seal the joints between sections of clay pipe has deteriorated. „ Undersized sewer pipe - The existing sewer system is overloaded due to new sewer hook- ups, underground water infiltration, and illegal roof and/or yard drain connections. „ Defective manholes - Old manholes are made of bricks. Typical problems associated with brick manholes are loose bricks, missing bricks, and misaligned manholes. „ Missing and/or unrecorded sewer pipes and manholes - This problem is typical in the easement/backline sewer. Sewer pipe locations shown on the sewer record map are different from the actual sewer location. „ Sewer main under houses and other improvements - Complaints of sewer main alignment crossing the house and other improvements. A solution to this problem requires an agreement with the property owner for a new sewer easement at a relocated line. Causes of Sanitary Sewer Backups „ Root infiltration - Tree roots are a major cause of backups. „ Water inflow/infiltration - Rain water entering the sewer pipe causes overflows. „ Solids - Typical solids that buildup in the pipe and cause backups are grease, dirt, bones, tampons, paper towels, diapers, broken dishware, garbage, concrete, and debris. „ Structural defects in pipes and manholes - Sags in the line, cracks, holes, protruding laterals, misaligned pipe, offset joints are all possible causes of backups. Water & Sewer Utility Maintenance SC-76 January 2003 California Stormwater BMP Handbook 7 of 8 Municipal www.cabmphandbooks.com Design Considerations Sanitary sewer overflows can often be reduced or eliminated by a number of practices, in addition to sewer system cleaning and maintenance, including the following: „ Reducing infiltration and inflow through rehabilitation and repair of broken or leaking sewer lines. „ Enlarging or upgrading the capacity of sewer lines, pump stations, or sewage treatment plants. „ Constructing wet weather storage and treatment facilities to treat excess flows. „ Addressing SSOs during sewer system master planning and facilities planning. Septic Systems Two field screening techniques that have been used with success at identifying possible locations of failing septic systems are the brightener test and color infrared (CIR) aerial photography. The first involves the use of specific phosphorus-based elements found in many laundry products, often called brighteners, as an indicator of the presence of failing onsite wastewater systems. The second technique uses color infrared (CIR) aerial photography to characterize the performance of septic systems. This method has been found to be a quick and cost-effective method for assessing the potential impacts of failing systems and uses variations in vegetative growth or stress patterns over septic system field lines to identify those systems that may potentially be malfunctioning. Then a more detailed onsite visual and physical inspection will confirm whether the system has truly failed and the extent of the repairs needed. These inspections may be carried out by county health departments or other authorized personnel. References and Resources Alameda Countywide Clean Water Program on-line http://www.ci.berkeley.ca.us/pw/Storm/stormala.html Los Angeles County Stormwater Quality. Public Agency Activities Model Program. On-line: http://ladpw.org/wmd/npdes/public_TC.cfm Orange County Stormwater Program http://www.ocwatersheds.com/StormWater/swp_introduction.asp Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. Santa Clara Valley Urban Runoff Pollution Prevention Program. 1998. Water Utility Operation and Maintenance Discharge Pollution Prevention Plan. June United States Environmental Protection Agency (USEPA). 2001. Illicit Discharge Detection and Elimination. On-line: http://cfpub.epa.gov/npdes/stormwater/menuofbmps/illi_1.cfm SC-76 Water & Sewer Utility Maintenance 8 of 8 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com United States Environmental Protection Agency (USEPA). 2001. Pollution Prevention/Good Housekeeping for Municipal Operators Septic System Controls. On-line: http://www.epa.gov/npdes/menuofbmps/poll_14.htm Infiltration Basin TC-11 January 2003 California Stormwater BMP Handbook 1 of 8 New Development and Redevelopment www.cabmphandbooks.com Description An infiltration basin is a shallow impoundment that is designed to infiltrate stormwater. Infiltration basins use the natural filtering ability of the soil to remove pollutants in stormwater runoff. Infiltration facilities store runoff until it gradually exfiltrates through the soil and eventually into the water table. This practice has high pollutant removal efficiency and can also help recharge groundwater, thus helping to maintain low flows in stream systems. Infiltration basins can be challenging to apply on many sites, however, because of soils requirements. In addition, some studies have shown relatively high failure rates compared with other management practices. California Experience Infiltration basins have a long history of use in California, especially in the Central Valley. Basins located in Fresno were among those initially evaluated in the National Urban Runoff Program and were found to be effective at reducing the volume of runoff, while posing little long-term threat to groundwater quality (EPA, 1983; Schroeder, 1995). Proper siting of these devices is crucial as underscored by the experience of Caltrans in siting two basins in Southern California. The basin with marginal separation from groundwater and soil permeability failed immediately and could never be rehabilitated. Advantages „ Provides 100% reduction in the load discharged to surface waters. „ The principal benefit of infiltration basins is the approximation of pre-development hydrology during which a Design Considerations „ Soil for Infiltration „ Slope „ Aesthetics Targeted Constituents ; Sediment „ ; Nutrients „ ; Trash „ ; Metals „ ; Bacteria „ ; Oil and Grease „ ; Organics „ Legend (Removal Effectiveness) z Low „ High ▲ Medium TC-11 Infiltration Basin 2 of 8 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com significant portion of the average annual rainfall runoff is infiltrated and evaporated rather than flushed directly to creeks. „ If the water quality volume is adequately sized, infiltration basins can be useful for providing control of channel forming (erosion) and high frequency (generally less than the 2-year) flood events. Limitations „ May not be appropriate for industrial sites or locations where spills may occur. „ Infiltration basins require a minimum soil infiltration rate of 0.5 inches/hour, not appropriate at sites with Hydrologic Soil Types C and D. „ If infiltration rates exceed 2.4 inches/hour, then the runoff should be fully treated prior to infiltration to protect groundwater quality. „ Not suitable on fill sites or steep slopes. „ Risk of groundwater contamination in very coarse soils. „ Upstream drainage area must be completely stabilized before construction. „ Difficult to restore functioning of infiltration basins once clogged. Design and Sizing Guidelines „ Water quality volume determined by local requirements or sized so that 85% of the annual runoff volume is captured. „ Basin sized so that the entire water quality volume is infiltrated within 48 hours. „ Vegetation establishment on the basin floor may help reduce the clogging rate. Construction/Inspection Considerations „ Before construction begins, stabilize the entire area draining to the facility. If impossible, place a diversion berm around the perimeter of the infiltration site to prevent sediment entrance during construction or remove the top 2 inches of soil after the site is stabililized. Stabilize the entire contributing drainage area, including the side slopes, before allowing any runoff to enter once construction is complete. „ Place excavated material such that it can not be washed back into the basin if a storm occurs during construction of the facility. „ Build the basin without driving heavy equipment over the infiltration surface. Any equipment driven on the surface should have extra-wide (“low pressure”) tires. Prior to any construction, rope off the infiltration area to stop entrance by unwanted equipment. „ After final grading, till the infiltration surface deeply. „ Use appropriate erosion control seed mix for the specific project and location. Infiltration Basin TC-11 January 2003 California Stormwater BMP Handbook 3 of 8 New Development and Redevelopment www.cabmphandbooks.com Performance As water migrates through porous soil and rock, pollutant attenuation mechanisms include precipitation, sorption, physical filtration, and bacterial degradation. If functioning properly, this approach is presumed to have high removal efficiencies for particulate pollutants and moderate removal of soluble pollutants. Actual pollutant removal in the subsurface would be expected to vary depending upon site-specific soil types. This technology eliminates discharge to surface waters except for the very largest storms; consequently, complete removal of all stormwater constituents can be assumed. There remain some concerns about the potential for groundwater contamination despite the findings of the NURP and Nightingale (1975; 1987a,b,c; 1989). For instance, a report by Pitt et al. (1994) highlighted the potential for groundwater contamination from intentional and unintentional stormwater infiltration. That report recommends that infiltration facilities not be sited in areas where high concentrations are present or where there is a potential for spills of toxic material. Conversely, Schroeder (1995) reported that there was no evidence of groundwater impacts from an infiltration basin serving a large industrial catchment in Fresno, CA. Siting Criteria The key element in siting infiltration basins is identifying sites with appropriate soil and hydrogeologic properties, which is critical for long term performance. In one study conducted in Prince George's County, Maryland (Galli, 1992), all of the infiltration basins investigated clogged within 2 years. It is believed that these failures were for the most part due to allowing infiltration at sites with rates of less than 0.5 in/hr, basing siting on soil type rather than field infiltration tests, and poor construction practices that resulted in soil compaction of the basin invert. A study of 23 infiltration basins in the Pacific Northwest showed better long-term performance in an area with highly permeable soils (Hilding, 1996). In this study, few of the infiltration basins had failed after 10 years. Consequently, the following guidelines for identifying appropriate soil and subsurface conditions should be rigorously adhered to. „ Determine soil type (consider RCS soil type ‘A, B or C’ only) from mapping and consult USDA soil survey tables to review other parameters such as the amount of silt and clay, presence of a restrictive layer or seasonal high water table, and estimated permeability. The soil should not have more than 30% clay or more than 40% of clay and silt combined. Eliminate sites that are clearly unsuitable for infiltration. „ Groundwater separation should be at least 3 m from the basin invert to the measured ground water elevation. There is concern at the state and regional levels of the impact on groundwater quality from infiltrated runoff, especially when the separation between groundwater and the surface is small. „ Location away from buildings, slopes and highway pavement (greater than 6 m) and wells and bridge structures (greater than 30 m). Sites constructed of fill, having a base flow or with a slope greater than 15% should not be considered. „ Ensure that adequate head is available to operate flow splitter structures (to allow the basin to be offline) without ponding in the splitter structure or creating backwater upstream of the splitter. TC-11 Infiltration Basin 4 of 8 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com „ Base flow should not be present in the tributary watershed. Secondary Screening Based on Site Geotechnical Investigation „ At least three in-hole conductivity tests shall be performed using USBR 7300-89 or Bouwer- Rice procedures (the latter if groundwater is encountered within the boring), two tests at different locations within the proposed basin and the third down gradient by no more than approximately 10 m. The tests shall measure permeability in the side slopes and the bed within a depth of 3 m of the invert. „ The minimum acceptable hydraulic conductivity as measured in any of the three required test holes is 13 mm/hr. If any test hole shows less than the minimum value, the site should be disqualified from further consideration. „ Exclude from consideration sites constructed in fill or partially in fill unless no silts or clays are present in the soil boring. Fill tends to be compacted, with clays in a dispersed rather than flocculated state, greatly reducing permeability. „ The geotechnical investigation should be such that a good understanding is gained as to how the stormwater runoff will move in the soil (horizontally or vertically) and if there are any geological conditions that could inhibit the movement of water. Additional Design Guidelines (1) Basin Sizing - The required water quality volume is determined by local regulations or sufficient to capture 85% of the annual runoff. (2) Provide pretreatment if sediment loading is a maintenance concern for the basin. (3) Include energy dissipation in the inlet design for the basins. Avoid designs that include a permanent pool to reduce opportunity for standing water and associated vector problems. (4) Basin invert area should be determined by the equation: where A = Basin invert area (m2) WQV = water quality volume (m3) k = 0.5 times the lowest field-measured hydraulic conductivity (m/hr) t = drawdown time ( 48 hr) (5) The use of vertical piping, either for distribution or infiltration enhancement shall not be allowed to avoid device classification as a Class V injection well per 40 CFR146.5(e)(4). kt WQVA= Infiltration Basin TC-11 January 2003 California Stormwater BMP Handbook 5 of 8 New Development and Redevelopment www.cabmphandbooks.com Maintenance Regular maintenance is critical to the successful operation of infiltration basins. Recommended operation and maintenance guidelines include: „ Inspections and maintenance to ensure that water infiltrates into the subsurface completely (recommended infiltration rate of 72 hours or less) and that vegetation is carefully managed to prevent creating mosquito and other vector habitats. „ Observe drain time for the design storm after completion or modification of the facility to confirm that the desired drain time has been obtained. „ Schedule semiannual inspections for beginning and end of the wet season to identify potential problems such as erosion of the basin side slopes and invert, standing water, trash and debris, and sediment accumulation. „ Remove accumulated trash and debris in the basin at the start and end of the wet season. „ Inspect for standing water at the end of the wet season. „ Trim vegetation at the beginning and end of the wet season to prevent establishment of woody vegetation and for aesthetic and vector reasons. „ Remove accumulated sediment and regrade when the accumulated sediment volume exceeds 10% of the basin. „ If erosion is occurring within the basin, revegetate immediately and stabilize with an erosion control mulch or mat until vegetation cover is established. „ To avoid reversing soil development, scarification or other disturbance should only be performed when there are actual signs of clogging, rather than on a routine basis. Always remove deposited sediments before scarification, and use a hand-guided rotary tiller, if possible, or a disc harrow pulled by a very light tractor. Cost Infiltration basins are relatively cost-effective practices because little infrastructure is needed when constructing them. One study estimated the total construction cost at about $2 per ft (adjusted for inflation) of storage for a 0.25-acre basin (SWRPC, 1991). As with other BMPs, these published cost estimates may deviate greatly from what might be incurred at a specific site. For instance, Caltrans spent about $18/ft3 for the two infiltration basins constructed in southern California, each of which had a water quality volume of about 0.34 ac.-ft. Much of the higher cost can be attributed to changes in the storm drain system necessary to route the runoff to the basin locations. Infiltration basins typically consume about 2 to 3% of the site draining to them, which is relatively small. Additional space may be required for buffer, landscaping, access road, and fencing. Maintenance costs are estimated at 5 to 10% of construction costs. One cost concern associated with infiltration practices is the maintenance burden and longevity. If improperly maintained, infiltration basins have a high failure rate. Thus, it may be necessary to replace the basin with a different technology after a relatively short period of time. TC-11 Infiltration Basin 6 of 8 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com References and Sources of Additional Information Caltrans, 2002, BMP Retrofit Pilot Program Proposed Final Report, Rpt. CTSW-RT-01-050, California Dept. of Transportation, Sacramento, CA. Galli, J. 1992. Analysis of Urban BMP Performance and Longevity in Prince George's County, Maryland. Metropolitan Washington Council of Governments, Washington, DC. Hilding, K. 1996. Longevity of infiltration basins assessed in Puget Sound. Watershed Protection Techniques 1(3):124–125. Maryland Department of the Environment (MDE). 2000. Maryland Stormwater Design Manual. http://www.mde.state.md.us/environment/wma/stormwatermanual. Accessed May 22, 2002. Metzger, M. E., D. F. Messer, C. L. Beitia, C. M. Myers, and V. L. Kramer. 2002. The Dark Side Of Stormwater Runoff Management: Disease Vectors Associated With Structural BMPs. Stormwater 3(2): 24-39. Nightingale, H.I., 1975, “Lead, Zinc, and Copper in Soils of Urban Storm-Runoff Retention Basins,” American Water Works Assoc. Journal. Vol. 67, p. 443-446. Nightingale, H.I., 1987a, “Water Quality beneath Urban Runoff Water Management Basins,” Water Resources Bulletin, Vol. 23, p. 197-205. Nightingale, H.I., 1987b, “Accumulation of As, Ni, Cu, and Pb in Retention and Recharge Basin Soils from Urban Runoff,” Water Resources Bulletin, Vol. 23, p. 663-672. Nightingale, H.I., 1987c, “Organic Pollutants in Soils of Retention/Recharge Basins Receiving Urban Runoff Water,” Soil Science Vol. 148, pp. 39-45. Nightingale, H.I., Harrison, D., and Salo, J.E., 1985, “An Evaluation Technique for Ground- water Quality Beneath Urban Runoff Retention and Percolation Basins,” Ground Water Monitoring Review, Vol. 5, No. 1, pp. 43-50. Oberts, G. 1994. Performance of Stormwater Ponds and Wetlands in Winter. Watershed Protection Techniques 1(2): 64–68. Pitt, R., et al. 1994, Potential Groundwater Contamination from Intentional and Nonintentional Stormwater Infiltration, EPA/600/R-94/051, Risk Reduction Engineering Laboratory, U.S. EPA, Cincinnati, OH. Schueler, T. 1987. Controlling Urban Runoff: A Practical Manual for Planning and Designing Urban BMPs. Metropolitan Washington Council of Governments, Washington, DC. Schroeder, R.A., 1995, Potential For Chemical Transport Beneath a Storm-Runoff Recharge (Retention) Basin for an Industrial Catchment in Fresno, CA, USGS Water-Resource Investigations Report 93-4140. Infiltration Basin TC-11 January 2003 California Stormwater BMP Handbook 7 of 8 New Development and Redevelopment www.cabmphandbooks.com Southeastern Wisconsin Regional Planning Commission (SWRPC). 1991. Costs of Urban Nonpoint Source Water Pollution Control Measures. Southeastern Wisconsin Regional Planning Commission, Waukesha, WI. U.S. EPA, 1983, Results of the Nationwide Urban Runoff Program: Volume 1 – Final Report, WH-554, Water Planning Division, Washington, DC. Watershed Management Institute (WMI). 1997. Operation, Maintenance, and Management of Stormwater Management Systems. Prepared for U.S. Environmental Protection Agency Office of Water, Washington, DC. Information Resources Center for Watershed Protection (CWP). 1997. Stormwater BMP Design Supplement for Cold Climates. Prepared for U.S. Environmental Protection Agency Office of Wetlands, Oceans and Watersheds. Washington, DC. Ferguson, B.K., 1994. Stormwater Infiltration. CRC Press, Ann Arbor, MI. USEPA. 1993. Guidance to Specify Management Measures for Sources of Nonpoint Pollution in Coastal Waters. EPA-840-B-92-002. U.S. Environmental Protection Agency, Office of Water, Washington, DC. TC-11 Infiltration Basin 8 of 8 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com Isolator® Row Plus O&M Manual 2 Looking down the Isolator Row PLUS from the manhole opening, ADS PLUS Fabric is shown between the chamber and stone base. StormTech Isolator Row PLUS with Overflow Spillway (not to scale) The Isolator® Row Plus Introduction An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row Plus is a technique to inexpensively enhance Total Suspended Solids (TSS) and Total Phosphorus (TP) removal with easy access for inspection and maintenance. The Isolator Row Plus The Isolator Row Plus is a row of StormTech chambers, either SC-160, SC-310, SC-310-3, SC-740, DC-780, MC-3500 or MC-7200 models, that is surrounded with filter fabric and connected to a closely located manhole for easy access. The fabric-wrapped chambers provide for sediment settling and filtration as stormwater rises in the Isolator Row Plus and passes through the filter fabric. The open bottom chambers and perforated sidewalls (SC-310, SC- 310-3 and SC-740 models) allow stormwater to flow both vertically and horizontally out of the chambers. Sediments are captured in the Isolator Row Plus protecting the adjacent stone and chambers storage areas from sediment accumulation. ADS geotextile fabric is placed between the stone and the Isolator Row Plus chambers. The woven geotextile provides a media for stormwater filtration, a durable surface for maintenance, prevents scour of the underlying stone and remains intact during high pressure jetting. A non-woven fabric is placed over the chambers to provide a filter media for flows passing through the chamber’s sidewall. The non-woven fabric is not required over the SC-160, DC-780, MC-3500 or MC-7200 models as these chambers do not have perforated side walls. The Isolator Row Plus is designed to capture the “first flush” runoff and offers the versatility to be sized on a volume basis or a flow-rate basis. An upstream manhole provides access to the Isolator Row Plus and includes a high/low concept such that stormwater flow rates or volumes that exceed the capacity of the Isolator Row Plus bypass through a manifold to the other chambers. This is achieved with an elevated bypass manifold or a high-flow weir. This creates a differential between the Isolator Row Plus row of chambers and the manifold to the rest of the system, thus allowing for settlement time in the Isolator Row Plus. After Stormwater flows through the Isolator Row Plus and into the rest of the chamber system it is either exfiltrated into the soils below or passed at a controlled rate through an outlet manifold and outlet control structure. The Isolator Row FLAMPTM (patent pending) is a flared end ramp apparatus attached to the inlet pipe on the inside of the chamber end cap. The FLAMP provides a smooth transition from pipe invert to fabric bottom. It is configured to improve chamber function performance by enhancing outflow of solid debris that would otherwise collect at the chamber's end. It also serves to improve the fluid and solid flow into the access pipe during maintenance and cleaning and to guide cleaning and inspection equipment back into the inlet pipe when complete. The Isolator Row Plus may be part of a treatment train system. The treatment train design and pretreatment device selection by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, StormTech recommend using the Isolator Row Plus to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row Plus. 3 Inspection The frequency of inspection and maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, percent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspections. Initially, the Isolator Row Plus should be inspected every 6 months for the first year of operation. For subsequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row Plus incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to determine the depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row Plus, clean-out should be performed. Maintenance The Isolator Row Plus was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for maintenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water nozzle to propel itself down the Isolator Row Plus while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the manhole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for culverts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. StormTech recommends a maximum nozzle pressure of 2000 psi be utilized during cleaning. JetVac reels can vary in length. For ease of maintenance, ADS recommends Isolator Row Plus lengths up to 200' (61 m). The JetVac process shall only be performed on StormTech Isolator Row Plus that have ADS Plus Fabric (as specified by StormTech) over their angular base stone. Isolator Row Plus Inspection/Maintenance StormTech Isolator Row PLUS (not to scale) Note: Non-woven fabric is only required over the inlet pipe connection into the end cap for SC-160LP, DC-780, MC-3500 and MC-7200 chamber models and is not required over the entire Isolator Row PLUS. Isolator Row Plus Step By Step Maintenance Procedures Step 1 Inspect Isolator Row Plus for sediment. A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod,measure depth of sediment and record results on maintenance log. iv. If sediment is at or above 3 inch depth, proceed to Step 2. If not, proceed to Step 3. B) All Isolator Row Plus i. Remove cover from manhole at upstream end of Isolator Row Plus ii. Using a flashlight, inspect down Isolator Row Plus through outlet pipe 1. Mirrors on poles or cameras may be used to avoid a confined space entry 2. Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches), proceed to Step 2. If not, proceed to Step 3. Step 2 Clean out Isolator Row Plus using the JetVac process. A) A fixed floor cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3 Replace all caps, lids and covers, record observations and actions. Step 4 Inspect & clean catch basins and manholes upstream of the StormTech system. ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. StormTech® and the Isolator® Row Plus are registered trademarks of StormTech, Inc. © 2022 Advanced Drainage Systems, Inc. #11081 2/22 CS  )( Sample Maintenance Log Date Stadia Rod Readings Sedi- ment Depth (1)–(2) Observations/Actions InspectorFixed point to chamber bottom (1) Fixed point to top of sediment (2) 3/15/11 6.3 ft none New installation. Fixed point is CI frame at grade DJM 9/24/11 6.2 0.1 ft Some grit felt SM 6/20/13 5.8 0.5 ft Mucky feel, debris visible in manhole and in Isolator Row PLUS, maintenance due NV 7/7/13 6.3 ft 0 System jetted and vacuumed DJM adspipe.com 800-821-6710 PREVENTING MOSQUITOESGuidelines to Reduce and Eliminate Mosquito Breeding Sites in the Coachella Valley PREVENTING MOSQUITOESGuidelines to Reduce and Eliminate Mosquito Breeding Sites in the Coachella Valley INTRODUCTION ......................................................................1 Why Should You Care about Preventing Mosquitoes? ..........................2 Basic Mosquito Biology ........................................................................3 Standing Water Mosquitoes .............................................................4 Flood Water Mosquitoes ...................................................................5 MOSQUITO REDUCTION BEST MANAGEMENT PRACTICES (BMPs) ...............................7 Universally Applicable Mosquito Control BMPs ....................................8 Residential Properties ...........................................................................9 Tire Storage ........................................................................................12 Pastures and Agricultural Properties ..................................................13 Ditches and Drains .........................................................................13 Irrigated Pastures ...........................................................................14 Wetlands .............................................................................................15 Storm Water Management and Infrastructures ..................................18 ABATEMENT AND HEALTH AND SAFETY CODE ......................20 www.cvmvcd.org 1 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites Controlling mosquitoes is critical to maintaining both a high quality of life and protecting people from mosquito-transmitted (vectored) diseases such as West Nile virus (WNV). These guidelines provide property owners and managers of homeowner associations (HOAs), country clubs, golf courses, and agricultural land with Best Management Practices for mosquito reduction. By implementing the following best practices property owners and managers can: • Reduce mosquito production from permanent water sources • Reduce or eliminate mosquito production from temporary water sources • Reduce the potential for disease transmission to humans. These guidelines are based on the California Department of Public Health (CDPH)/Mosquito and Vector Control Association of California (MVCAC) Best Management Practices guide and are intended to assist property owners and managers. The recommended practices, when properly implemented, are in line with best practices for water conservation and can lead to reductions in water usage and cost, while increasing the efficacy of biological and chemical control measures for mosquitoes. INTRODUCTION Coachella Valley Mosquito and Vector Control District 2 (760) 342-8287 MOSQUITOES VECTOR DISEASE About 12 mosquito species have been detected in the Coachella Valley. Two of those species currently are vectors (or transmitters) of disease agents to humans within the Coachella Valley. The Encephalitis Mosquito (Culex tarsalis) has been known to transmit West Nile virus, western equine encephalomyelitis, and St. Louis encephalitis. The Southern House Mosquito (Culex quinquefasciatus) can transmit West Nile virus and St. Louis encephalitis. These diseases can have permanent impacts on the nervous system and in rare cases lead to death. The only method to prevent contracting these diseases is to prevent being bitten by mosquitoes. An invasive mosquito species, Aedes aegypti, has also been detected in the Coachella Valley. This mosquito species is capable of transmitting dangerous viruses, such as dengue, chikungunya, and Zika, however, currently there is no local mosquito transmission of these viruses. MOSQUITOES ARE A NUISANCE THAT WE CAN REDUCE Immature mosquitoes live in standing water. We can reduce mosquito populations by reducing the amount of standing water present in the Coachella Valley. MOSQUITO PREVENTION IS THE LAW Under the California Health and Safety Code, mosquito and vector control districts may legally abate a public nuisance defined as “Any water that is a breeding place for vectors” and “Any activity that supports the development, attraction, or harborage of vectors, or that facilitates the introduction or spread of vectors” (HSC §2002(j)). Abatement can result in civil penalties of up to $1000 per day (HSC §2085(a), §2061). WHY SHOULD YOU CARE ABOUT PREVENTING MOSQUITOES? www.cvmvcd.org 3 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites BASIC MOSQUITO BIOLOGY Mosquitoes have aquatic stages (larva and pupa) and an aerial stage (adult). Mosquito larvae breathe air from above the water surface and most hang at an angle from or lay parallel with the surface of the water while consuming small bits of organic matter. When disturbed, larvae swim down into the water column in a serpentine motion (giving rise to their common names of wigglers and wrigglers). Mosquitoes then go through a non-feeding stage called a pupa. The easily identified comma-shaped pupae hang from the water surface and move down through the water column in a rolling or tumbling motion when disturbed. This life stage typically lasts about a day, with the mosquito emerging from the back of the pupal case (above the water) as a flying adult mosquito. All adult mosquitoes feed on plant nectar; however blood is essential for female mosquitoes to produce eggs. To take a blood meal, the female’s mouth parts pierce the skin, inject saliva, and suck blood out. It is through the injection of saliva that a mosquito causes the typical itchy bump and can infect a person or domestic animal with a disease causing organism. Depending on an individual’s immune response, even a single bite can be a significant nuisance. Typically, mosquitoes in the Coachella Valley are divided into standing water species and floodwater species. THE MOSQUITO LIFE CYCLE Coachella Valley Mosquito and Vector Control District 4 (760) 342-8287 Standing water species are found in areas where water is allowed to pool and stagnate. Adult mosquitoes lay eggs on the water surface. The eggs float for a few hours to a few days until the larvae hatch in the water. These species can develop in containers, neglected swimming pools, catch basins, open ditches, retention/detention ponds, natural or constructed wetlands, storm water management devices, and along the edges of flowing streams. The Encephalitis Mosquito (Culex tarsalis) can transmit encephalitis viruses, such as West Nile virus, to humans. It can be found throughout the Coachella Valley. Immature mosquitoes develop in wetlands, duck clubs, irrigated crop fields, and neglected pools. The adult mosquito prefers to feed on birds and mammals. It is most active during spring, summer, and fall. The Southern House Mosquito (Culex quinquefasciatus) is a secondary vector of West Nile virus and St. Louis encephalitis. It is common throughout the Coachella Valley. Immature mosquitoes often develop in foul water sources such as wastewater lagoons, storm water drains, neglected pools, and other containers. It prefers to feed on birds but will readily feed on humans. This mosquito is most active during the spring, summer, and fall. STANDING WATER MOSQUITOES Culex tarsalis Culex quinquefasciatus www.cvmvcd.org 5 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites Floodwater mosquitoes lay eggs on mud or previously submerged vegetation. The eggs can hatch when the area becomes flooded with water, or they may remain dormant for days to years until the right conditions are available. Floodwater mosquito development sites include irrigated pastures and seasonally flooded duck clubs. These intermittent or seasonally flooded habitats can be among the most productive sources of mosquitoes because they are often free of natural predators. Psorophora columbiae is a severe outdoor pest in rural areas of the Coachella Valley. The primary sources of these mosquitoes are flood irrigated agricultural fields and pastures. It is present from early summer to late fall. This mosquito prefers to feed on large mammals, including humans, and will bite both day and night with a peak of activity at sunrise and sunset. It can complete development from egg to adult within 3 to 5 days during the extreme temperatures of summer, which makes control of this species very difficult. The Inland Floodwater Mosquito (Aedes vexans) is a secondary vector of dog heartworm and is a severe outdoor pest. It is common in irrigated pastures and in woodland water course pools. The adults feed mainly on mammals. This mosquito is most active in early spring through late fall. They typically bite at dawn and dusk but can also be active during the day. FLOODWATER MOSQUITOES Psorophora columbiae Aedes vexans www.cvmvcd.org 7 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites The Coachella Valley Mosquito and Vector Control District (District) uses an Integrated Vector Management (IVM) approach to mosquito and vector control. The IVM approach focuses on site-specific, scientifically sound decisions to target the solution to the problem at hand. Typically, the techniques for controlling vectors are grouped into the following categories: 1. SOURCE REDUCTION OR PHYSICAL CONTROL manipulating the habitat to reduce mosquito breeding sites 2. CULTURAL CONTROL changing the behavior of people so that their actions prevent the development of mosquitoes or the transmission of vector-borne diseases 3. BIOLOGICAL CONTROL adding an animal to the environment that will eat the mosquitoes, for example, adding mosquitofish to a golf course pond 4. CHEMICAL CONTROL using larvicides (materials designed to kill immature larval mosquitoes) and adulticides (materials that kill adult mosquitoes) Every site is unique. After evaluating the source of the mosquitoes, we implement the mosquito control practices applicable to the circumstances. We encourage property owners and managers to also use appropriate best practices as an efficient and effective way to help prevent a mosquito problem. Fortunately, many of the steps in these guidelines are affordable and easy to implement. MOSQUITO REDUCTION BEST MANAGEMENT PRACTICES (BMPs) Coachella Valley Mosquito and Vector Control District 8 (760) 342-8287 UNIVERSALLY APPLICABLE MOSQUITO CONTROL BMPs GENERAL PRINCIPLES 1. Prevent or eliminate unnecessary standing water that remains for more than 96 hours. 2. Maintain water features such as ponds and fountains to circulate water with pumps that run at least eight hours a day. If the feature has no pump, water should be changed every 96 hours to prevent mosquito breeding and/or pesticide treatment may be necessary. 3. Maintain irrigation systems to avoid excess water use and runoff into storm drains. 4. Apply an EPA-registered mosquito repellent when outdoors; especially around dusk and dawn when mosquitoes are most active. 5. Wear loose-fitting protective clothing including long sleeves and pant legs. 6. Install and properly maintain fine mesh screens on windows and doors to prevent mosquito entry into homes. 7. Contact the District for technical guidance or assistance to prevent a mosquito problem on your property. 8. Maintain access for District staff to monitor and treat mosquito breeding sources. 9. Train and inform homeowners and landscape and maintenance staff about Best Management Practices and personal protective measures such as irrigation and landscape maintenance to reduce mosquito breeding potential of sites commonly found in urban environments. COLLABORATE WITH LOCAL MOSQUITO CONTROL PROGRAM 1. Contact the District to evaluate your property for mosquito breeding sites to prevent a mosquito problem on your property. 2. Ensure mosquito control technicians are able to easily access and treat mosquito breeding sites. www.cvmvcd.org 9 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites Urban and suburban mosquito sources are especially problematic because they produce mosquitoes in areas of high population density where many people live and work. This can quickly lead to mosquito– borne disease transmission since mosquitoes and humans are often in close proximity. Follow these guidelines to reduce the chances of people getting sick in your community. PROPERTY MAINTENANCE – Eliminate man-made mosquito breeding sites and harborage: 1. Examine outdoor areas and drain temporary and unnecessary water that may stand longer than 96 hours. 2. Be aware of containers and objects that are subject to collecting water including pet dishes, potted plant drip trays, boats, birdbaths, and tires and buckets. Change water at least once per week. Mosquitoes can develop in as little as a 1/8” of standing water. Dispose of unwanted or unused artificial containers. 3. If possible, drill drainage holes, cover, or invert any container or object, that holds standing water and must remain outdoors. Be sure to check for containers or trash in places that may be hard to see, such as under bushes or buildings. 4. Ensure regular chlorination of swimming pools and that pumps and filters are operating. Unused or unwanted pools should be kept empty and dry. If a pool or spa is not going to be operational for any reason, notify the District so that the pool or spa can be inspected regularly and treated with an appropriate larvicide and/or stocked with mosquitofish, if needed. These services are provided at no additional charge and are supported by property taxes. RESIDENTIAL PROPERTIES Coachella Valley Mosquito and Vector Control District 10 (760) 342-8287 5. Properly dispose of any old tires that may collect water. 6. Clean clogged rain gutters and storm drains. Keep outdoor drains flowing freely and clear of leaves, vegetation, and other debris. 7. Use waterfalls, fountains, aerators and/or mosquitofish in ponds and ornamental water features. Mosquitofish are provided by the District at no charge. For ponds and ornamental water features where mosquitofish cannot be used, landowners should contact the District. 8. Minimize sites mosquitoes can use for refuge (harborage) by thinning branches, trimming and pruning ornamental shrubs and bushes, and keeping grass mowed short. 9. Install screens on small drains and keep them free of water and debris. 10. Back-fill tire ruts or other low areas that hold water for more than 96 hours. www.cvmvcd.org 11 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites IRRIGATION AND DRAINAGE – Prevent mosquito breeding associated with poorly managed irrigation, drainage, and landscape features: 1. Manage sprinkler and irrigation systems to minimize runoff entering storm water infrastructure. Ensure appropriate sprinkler type and placement for the landscaping, e.g., Variable Arc Nozzle (VAN) sprinklers for small or odd-shaped lawns (should be placed at least 6 inches from sidewalks and streets), drip sprinklers should be used for flowerbeds or desert landscapes to prevent “watering” the streets and sidewalks. Reduce watering time and increase frequency to grass, plants, and trees to provide sufficient time to absorb the water without waste. 2. Routinely inspect, maintain, and repair irrigation system components. 3. All underground drain pipes should be laid to grade to avoid low areas that may hold water for longer than 96 hours. 4. Improve drainage channels and grading to minimize potential for standing water. 5. Keep ditches clean and well-maintained. Periodically remove accumulated sediment and vegetation. Maintain ditch grade and prevent areas of standing water. 6. Vegetation should be controlled regularly to prevent overgrowth of emergent vegetation and vegetative barriers for District access. This includes vegetation control to maintain access to lanes and paths, interior pond embankments, and any weed growth that might become established within the pond. Vegetation in water features provides a protected spot for mosquitoes to lay their eggs. 7. Check and repair leaky outdoor faucets. 8. Construct or improve large ditches to a slope of at least 2:1 and a minimum 4-foot wide bottom. Consider a 3:1 slope or greater to discourage burrowing animal damage, potential seepage problems, and prevent unwanted vegetation growth. 9. Design irrigation systems to use water efficiently and drain completely to avoid standing water. Prevent wet areas associated with seepage by repairing leaks in dams, ditches, and drains. 10. Use desert landscape/xeriscape to reduce water usage and wastage. Install curb set-backs to maintain space between turfgrass and the street; these can include placing rocks, a sidewalk or sections of desert landscaping adjacent to the street to minimize the risk of water runoff into the street. Coachella Valley Mosquito and Vector Control District 12 (760) 342-8287 Old tires can quickly become an area for mosquitoes to breed. These storage and inspection techniques will make it easy to control the mosquitoes. 1. Never allow water to accumulate in tires. Tires should be stored in a covered location or covered by a tarp in order to prevent the accumulation of water from rain or sprinklers. If water does accumulate, it should be dumped immediately. 2. Tires should never be stored in a pile. Tires should be stored on racks or in a stack not more than two rows wide – this allows for inspections of each tire. 3. Waste tires should be picked up by the proper disposal entity on a regular basis. TIRE STORAGE www.cvmvcd.org 13 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites Most floodwater mosquitoes develop on pasture and agricultural land in the Coachella Valley. Floodwater mosquitoes can become a severe nuisance in the surrounding community (see Basic Mosquito Biology). DITCHES AND DRAINS 1. Construct or improve ditches with at least 2:1 slopes and a minimum 4 foot bottom. Consider a 3:1 slope or greater to discourage burrowing animal damage, potential seepage problems, and prevent unwanted vegetation growth. 2. Keep ditches clean and well-maintained. Periodically remove accumulated sediment and vegetation. Maintain ditch grade to prevent areas of standing water. 3. Design irrigation systems to use water efficiently and drain completely to avoid standing water. PASTURES AND AGRICULTURAL PROPERTIES Coachella Valley Mosquito and Vector Control District 14 (760) 342-8287 IRRIGATED PASTURES 1. Grade field to achieve efficient use of irrigation water. Use Natural Resources Conservation Service (NRCS) guidelines for irrigated pastures. Initial laser leveling and periodic maintenance to repair damaged areas are needed to maintain efficient water flow. 2. Irrigate only as frequently as is needed to maintain proper soil moisture. Check soil moisture regularly until you know how your pasture behaves. 3. Do not over fertilize. Excess fertilizers can leach into irrigation tail water, making mosquito production more likely in ditches or further downstream. 4. Apply only enough water to wet the soil to the depth of rooting. 5. Drain excess water from the pasture within 24 hours following each irrigation period. This prevents scalding and reduces the number of weeds in the pasture. Good check slopes are needed to achieve drainage, and a drainage ditch may be used to remove water from the lower end of the field. 6. Inspect fields for drainage and broken checks to see whether re-leveling or reconstruction of levees is needed. Small low areas that hold water can be filled and replanted by hand. Broken checks create cross-leakage that provide habitat for mosquitoes. 7. Keep animals off the pasture while the soil is soft. An ideal mosquito habitat is created in irrigated pastures when water collects in hoof prints of livestock that were run on wet fields or left in the field during irrigation. Keeping animals off wet fields until soils stiffen also protects the roots of the forage crop and prevents soil compaction that interferes with plant growth. 8. Break up pastures into a number of smaller fields so that the animals can be rotated from one field to another. This allows fields to dry between irrigations and provides a sufficient growth period between grazing periods. It also prevents hoof damage, increases production from irrigated pastures, and helps improve water penetration into the soil by promoting a better root system. www.cvmvcd.org 15 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites Managed wetlands are found across California. Each wetland may vary in habitat, water quality, and its management goals. Wetlands in the Coachella Valley include permanent wetlands for habitat or species conservation, manmade waste water treatment wetlands, and temporarily flooded duck clubs. DESIGN AND MAINTENANCE – General Guiding Principles to Minimize Mosquitoes: 1. Identify problem locations for mosquito production with the District and work to implement mosquito BMPs. Consult with the District on the design of restoration and enhancement projects that have the possibility of effecting mosquito production or control operations. 2. Maintain all open ditches – regularly remove trash, silt, and vegetation to maintain efficient water delivery and drainage. 3. Ensure mosquito control technicians are able to easily access and treat mosquito breeding sites. Make shorelines of natural, agricultural, and constructed water bodies accessible to maintenance and vector control crews for periodic maintenance, control, and removal of emergent vegetation. WETLANDS Coachella Valley Mosquito and Vector Control District 16 (760) 342-8287 4. Inspect, repair, and clean water control structures of debris. Remove silt and vegetation build-up in front of structures that impedes drainage or water flow. Completely close, board or mud- up controls to prevent unnecessary water flow, except where water circulation is necessary. 5. Construct, improve, or maintain ditches with 2:1 slopes and a minimum 4 foot bottom. Consider a 3:1 slope or greater to discourage burrowing animal damage, potential seepage problems, and prevent unwanted vegetation growth. 6. Construct, or improve, or maintain levees to quality standard that ensures stability and prevents unwanted seepage. Ideally build levees with >3:1 slopes & >80% compaction; consider >5:1 slope or greater in areas prone to over-land flooding and levee erosion. 7. Inspect and repair levees at least annually. 8. Design managed wetland projects to include independent inlets and outlets for each wetland unit. 9. Excavate deep channels or basins to maintain permanent water areas (> 2.5 feet deep) within a portion of seasonal managed wetlands. This provides year-round habitat for mosquito predators which can inoculate seasonal wetlands when they are irrigated or flooded. 10. Provide nesting and roosting sites for birds and bats. They can feed on adult mosquitoes to help reduce the population. 11. Whenever possible, maintain wetlands at depths greater than 4 feet (1.2 m) to limit the spread of invasive emergent vegetation such as cattails and bulrush. www.cvmvcd.org 17 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites MANAGE VEGETATION – Keep the wetland productive and to make mosquito treatments easy: 1. Control floating vegetation conducive to mosquito production. 2. Perform routine maintenance to reduce emergent plant densities to allow mosquito predators (e.g., fish) to move throughout vegetated areas, and to allow good penetration of chemical control agents. WATER MANAGEMENT – To help reduce mosquitoes: 1. Minimize fluctuations in water level to prevent large areas of intermittently flooded substrate or isolated pools from being created, particularly during mosquito season. 2. Flood managed wetlands with water sources containing mosquitofish or invertebrate predators. Water from permanent ponds can be used to passively introduce mosquito predators. 3. Delay early fall flooding to avoid increased late-season mosquito production. Implement additional BMPs for managed wetlands that need to be flooded earlier than recommended in the fall. The wetlands targeted for early fall flooding should not be near urban centers and should not have a history of heavy mosquito production. 4. Flood managed wetlands as fast as possible. Coordinate flooding with neighbors or water district to maximize flood-up rate. 5. Encourage water circulation by providing a constant flow of water equal to discharge at drain structure. 6. Flood managed wetland as deep as possible at initial flood-up (18-24”). 7. Stock managed wetlands, especially brood ponds or permanent wetlands, with mosquitofish, or encourage habitat for naturalized populations. 8. Where feasible, have an emergency plan that provides for immediate drainage into acceptable areas if a public health emergency occurs. Coachella Valley Mosquito and Vector Control District 18 (760) 342-8287 The size and variability of storm water infrastructure, inconsistent quantity and timing of water flows, and tendency to carry and accumulate sediment, trash, and debris, make these systems highly conducive to holding areas of standing water ideal for production of mosquitoes. 1. Consider mosquito production during the design, construction, and maintenance of storm water infrastructure. Design and maintain systems to fully discharge captured water in 96 hours or less. Include access for maintenance in system design. 2. Design outfalls (discharge points) to prevent scour depressions that can hold standing water. 3. Design structures so that they do not hold standing water for more than 96 hours to prevent mosquito development. Features to prevent or reduce the possibility of clogged discharge orifices (e.g., debris screens, permeable pavers) should be incorporated into the design. 4. Design distribution pumping and containment basins with adequate slopes to drain fully. The design slope should take into consideration buildup of sediment between maintenance periods. 5. Inspect drains regularly for the presence of standing water or immature mosquitoes. STORM WATER MANAGEMENT AND INFRASTRUCTURES www.cvmvcd.org 19 Preventing Mosquitoes: Guidelines to Reduce and Eliminate Mosquito Breeding Sites 6. Provide proper grades along conveyance structures to ensure that water flows freely. 7. Provide a uniform grade between the inlets and outlets to ensure that all water is discharged in 96 hours or less. Routine inspection and maintenance are crucial to ensuring the grade remains as designed and to remove accumulations of sediment, trash, and debris. 8. Keep inlets free of accumulations of sediment, trash, and debris to prevent standing water from backing up on roadways and gutters. 9. Avoid the use of electric pumps. They are subject to failure and often require permanent-water sumps. Structures that do not require pumping should be favored over those that have this requirement. 10. Install tight-fitting covers and manhole cover inserts to minimize mosquito access to permanent sources of standing water. Coachella Valley Mosquito and Vector Control District 20 (760) 342-8287 ABATEMENT AND HEALTH AND SAFETY CODE Under the California Health and Safety Code (HSC), mosquito and vector control districts may legally abate a public nuisance, including areas that allow for the development, attraction, or harborage of mosquitoes or other vectors. Abatement can result in civil penalties of up to $1000.00 per day per violation (HSC §2085(a), §2061). The District begins correcting public nuisances through voluntary compliance from the property owners or parties in possession of property (Responsible Party). Persistent violators may be subject to additional enforcement action such as having the abatement work performed by the District at the Responsible Party’s expense or having civil penalties assessed against the Responsible Party. The District will inspect property to confirm and document that a public nuisance exists. From there, the District may issue a Request for Compliance, followed by a Notice of Violation if the nuisance is not remedied. If the issue is still not resolved, the District may issue a Notice of Public Nuisance and Order to Abate. OUR SERVICE AREA OUTLINED IN RED Watch the video: www.cvmvcd.org or www.youtube.com/ watch?v=TdTIg2nQs28 2 | Page What Happens When You Report a Mosquito Problem? District Call Center Clerks take a report and enter it into the District’s digital mobile application. 5,334 calls received by Call Center in 2015 757 calls complaining about mosquito problems A District state- certified Vector Control Technician will then be assigned to investigate the complaint. 24 technicians covering 2,400 square miles 63,622 inspections searching for mosquito larvae 276,021 mosquitoes were caught in District traps and of those 12 species were identified District lab technicians will prepare test tubes filled with anywhere from 5 to 50 mosquitoes per sample to be tested for viruses in the District Lab. 3,903 samples of mosquitoes tested 99 positive for West Nile virus 37 positive for Saint Louis encephalitis virus 15,860 larvicide treatments were made over 2,968 acres of residential, urban, and rural areas of the Coachella Valley Watch the Video at http://www.cvmvcd.org or http://www.youtube.com/watch?v=TdTIg2nQs28 WHAT HAPPENS WHEN YOU REPORT A MOSQUITO PROBLEM? COACHELLA VALLEY MOSQUITO AND VECTOR CONTROL DISTRICT Protection and Prevention since 1928 The Coachella Valley Mosquito and Vector Control District is a non-enterprise special district accountable to the residents of the Coachella Valley and charged with protecting the public health within its boundaries through the control of vectors (such as mosquitoes) and vector-borne diseases. The District boundary encompasses 2400 square miles, including Cathedral City, Coachella, Desert Hot Springs, Indian Wells, Indio, La Quinta, Palm Desert, Palm Springs, Rancho Mirage, and unincorporated sections of Riverside County. The District operates under the California Health and Safety Code, Division 3, Sections 2000-2910 and is governed by an 11-member Board of Trustees. There are 57 full-time employees and 3-6 seasonal staff from April to November. HELP US HELP YOU PROTECT YOUR COMMUNITYFIGHT THE BITE! COACHELLA VALLEY MOSQUITO AND VECTOR CONTROL DISTRICT 43-420 Trader Place, Indio, CA 92201 Mailing Address P.O. Box 2967, Indio, CA 92202 Toll-Free (888) 343-9399 District Office (760) 342-8287 District Fax (760) 342-8110 cvmosquito@cvmvcd.org www.CVMVCD.org 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix E Soils Report Double Ring Infiltration Testing and Report Proposed Automotive Dealership, March 2017 Percolation Test Summary Sheets, March 2022 CenterPoint Integrated Solutions  355 Union Boulevard, Suite 301  Lakewood, Colorado 80228  File No.: 12426‐02  Doc. No.: 17‐03‐716  Double Ring Infiltration Testing and Report  Proposed Automotive Dealership  73‐450 & 73‐500 Dinah Shore Drive  Palm Desert, Riverside County, California            March 30, 2017                                    © 2017 Earth Systems Southwest  Unauthorized use or copying of this document is strictly prohibited   without the express written consent of Earth Systems Southwest.          March 30, 2017 File No.: 12426‐02   Doc. No.: 17‐03‐716    CenterPoint Integrated Solutions  355 Union Boulevard, Suite 301  Lakewood, Colorado 80228    Attention:    Mr. Greg Saia    Subject: Double Ring Infiltration Testing and Report    Project: Proposed Automotive Dealership   73‐450 and 73‐500 Dinah Shore Drive    Palm Desert, Riverside County, California    Earth Systems Southwest (Earth Systems) presents this infiltration testing and report prepared  for the proposed Automotive Dealership project located along the north side of Dinah Shore  Drive at Gateway Drive in Palm Desert, Riverside County California.  The intent of this report is to  provide infiltration rate information for the development of two retention basins.  This report presents our findings and recommendations for infiltration of storm water disposal  at the proposed retention basins described further in this report.  This report should stand as a  whole and no part of the report should be excerpted or used to the exclusion of any other part.  This report completes our scope of services in accordance with our agreement Change Order No.  2, Control No.: 3185R, dated February 22, 2017 and Revised March 7, 2017.  Other services that  may be required, such as plan review and grading observation, are additional services and will be  billed according to our Fee Schedule in effect at the time services are provided.  Unless requested  in writing, the client is responsible for distributing this report to the appropriate governing agency  or other members of the design team.  We appreciate the opportunity to provide our professional services.  Please contact our office if  there are any questions or comments concerning this report or its recommendations.  Respectfully submitted,  EARTH SYSTEMS SOUTHWEST      Anthony Colarossi  Project Engineer, CE 60302    SER/ac/klp/mr  Distribution: Email/CenterPoint, Stacey Haggerson: shaggerson@centerpoint‐is.com    Email/Greg Saia: gsaia@centerpoint‐is.com    1/BD File  i  EARTH SYSTEMS GLOBAL  TABLE OF CONTENTS   Page  Section 1 INTRODUCTION ........................................................................................... 1  1.1 Project Description ........................................................................................... 1  1.2 Site Description ................................................................................................. 2  1.3 Purpose and Scope of Services ......................................................................... 2  Section 2 METHODS OF EXPLORATION AND TESTING .................................................. 4  2.1 Field Exploration ............................................................................................... 4  2.2 Soil Conditions .................................................................................................. 4  2.3 Groundwater ..................................................................................................... 4  2.4 Retention Basin Infiltration Testing .................................................................. 5  Section 3 LIMITATIONS AND ADDITIONAL SERVICES ................................................... 9  3.1 Uniformity of Conditions and Limitations ........................................................ 9  3.2 Additional Services .......................................................................................... 10  REFERENCES .......................................................................................................... 12  APPENDIX A  Plate 1 – Site Location Map  Plate 2 – Infiltration Test Location Map  Plate 3 – Project Soils Report Boring Location Map  Terms and Symbols Used on Boring Logs  Soil Classification System  Logs of Borings 4, 8, 9, 10, and 17 (Earth Systems, 2016)  March 30, 2017 1 File No.: 12426‐02    Doc. No.: 17‐03‐716    Double Ring Infiltration Testing and Report  Proposed Automotive Dealership  73‐450 & 73‐500 Dinah Shore Drive  Palm Desert, Riverside County, California    EARTH SYSTEMS GLOBAL  Section 1   INTRODUCTION  1.1 Project Description  This report has been prepared for the proposed commercial development to be located along  the north side of Dinah Shore Drive at Gateway Drive in Palm Desert, Riverside County, California.  We understand that site development will include a 4,419‐square foot sales building, a 2,427‐ square foot retail service building, a 634‐square foot presentation building, a 0.46‐acre sales  staging area with 62 parking spaces, a 1.63‐acre sales display area with 195 parking spaces, a  1.22‐acre customer employee parking area with 71 parking spaces, a 0.21‐acre detention area  and a 1.90 usable surplus area.   Infiltration for storm water disposal from the project site is proposed in the form of infiltration  at two locations having approximately two to three feet deep detention/retention basins located  onsite near the northeast corner and northwest corners of the property as shown in Figure 1  below. The infiltration test locations are shown in Figure 1 below (I‐1, I‐2, etc). Plate 2 in Appendix  A is also provided for additional clarity.  Figure 1    Infiltration Test Locations  March 30, 2017 2 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  1.2 Site Description    The project is located at 73‐450 and 73‐500 Dinah Shore Drive which is located along the north  side of Dinah Shore Drive across from Gateway Drive in the city of Palm Desert. The project  contains two legal lots (APN 694‐060‐011 and 694‐060‐012) and they are currently vacant. The  area of the parcels is approximately 6.12 acres total. From a 1996 photograph (Google earth  photo of the site, Imagery Date 6/3/1996) most of the site looks unused since 1996. Between  2004 and 2005 the current alignment of Dinah Shore Drive and Gateway Drive were constructed.  Currently the site is bounded by a commercial/retail building to the southeast, vacant land to the  northwest, railroad tracks and the Interstate Highway 10 freeway to the northeast and Dinah  Shore Drive along the southwest.  An existing lined drainage channel runs along the northern  perimeter of the site.  High voltage powerlines run adjacent to the northwestern side of the site.   Based on Google earth and the Riverside County Parcel report shows current elevations range  from about 200 feet at the northwest corner to a low elevation of approximately 195 feet at the  southeast corner of the project site.  The site is generally flat with a gentle dip toward the  southeast. Drainage appears to be by sheet flow, but drainage channels may be hidden by wind‐ blown sand.  Currently the site has sparse native vegetation consisting of small to medium sized  bushes.  No existing site improvements appear to be within the site.  The site location is shown  on Plate 1, Site Location Map in Appendix A.  1.3 Purpose and Scope of Services  The purpose for our services was to evaluate the infiltration rate of soils encountered at the test  locations and to provide professional opinions and recommendations regarding storm water  disposal using the proposed basin methods.  The scope of services included:  1. Surficial site conditions were visually assessed and selected published reports were reviewed  for the site, including prior reports by Earth Systems.  2. Near‐surface soil conditions were explored by means of drilling several exploratory borings  at the site which were logged (Earth Systems, 2016).    3. Engineering analysis of the data generated from this study was performed and a written  report prepared to present our findings and recommendations, which includes the following:   A description of the proposed project including a site plan showing the approximate test  pit locations;   A description of the surface and subsurface site conditions as encountered in Earth  Systems 2016 report;   An appendix, which includes a summary of the field testing program.  4. In general accordance with the guidelines of the Stormwater Quality Best Management  Practice Design Handbook (Riverside County, 2006), the scope of services for the infiltration  testing for storm water retention generally consisted of the following:     March 30, 2017 3 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL   Three test pits were excavated at the proposed locations of the basins.     Field infiltration testing at the bottom of the test pits were performed using Double‐Ring  Infiltrometer (ASTM D3385) at depths of approximately two and three feet below existing  grade at the test locations.   The data was organized and evaluated to identify subsurface site characteristics and site‐ specific infiltration rates for storm water disposal at the elevation of the proposed  systems.  March 30, 2017 4 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Section 2   METHODS OF EXPLORATION AND TESTING  2.1 Field Exploration  Three exploratory test pits were excavated to depths of approximately two and three feet below  existing surface so that test locations will represent the bottom of the proposed detention basins.  The pits were excavated on Thursday, March 23, 2017.  The test pit locations are shown on Plate  2 in Appendix A.  The locations shown are approximate, established by pacing and line‐of‐sight  bearings from adjacent landmarks.  2.2 Soil Conditions  Field exploration indicates that the upper surface (five feet) site soils consist predominantly of  poorly graded sand, poorly graded sand with silt, and silty sand, (Unified Soils Classification  System symbols of SP, SP‐SM, and SM).  From the 2016 Earth Systems report (page 7),   Figure 2     Excerpt from Project Soils Report  Observations of the project soils report logs (Earth Systems, 2016) shows clay and/or silt  interbedded layers/lenses/laminates are observed from the surface to depths of 10 to 15 feet.  However, some profiles show clay and silt interbeds to a depth of 20 feet.    2.3 Groundwater  Free groundwater was not encountered in the 2016 borings or during this reports infiltration  testing.  Also on page 7 of the Earth Systems report (2016), groundwater is estimated to be  greater than 100 feet below the ground surface, see figure below.     March 30, 2017 5 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Figure 3      Groundwater Section Excerpt from Project Soils Report    2.4 Retention Basin Infiltration Testing  To evaluate the soils encountered, three infiltration tests were performed. Testing was  performed at approximately two and three feet below existing grade. The infiltration testing was  performed with double‐ring infiltrometers, following the general guidelines contained in ASTM  D3385, Standard Test Method for Infiltration Rate of Soils in Field Using Double‐Ring Infiltrometer.  Double ring test procedures simulate the low water head conditions typically present during  shallow infiltration into basins.      For each test location and elevation, an approximately two to three feet deep pit was excavated  and the inner and outer rings of the test apparatus were driven with a sledgehammer into the  ground an additional approximate three inches. As necessary, powdered bentonite was placed  around the edges of the rings in order to create a watertight seal. Care was taken to not alter the  structure of the soil during hand excavation. Per ASTM test procedure, potable water was used  to evaluate the basic infiltration rate. The tests were performed for a period of at least 6 hours.  The soils encountered at each test location and the results of the infiltration testing are presented  in Table 1 below.        March 30, 2017 6 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Table 1  Infiltration Rates    Test  Location Test Description USCS Soil Description Estimated Basic   Stabilized Infiltration Rate* I‐1  Double Ring   Infiltrometer  (12” and 24”  Rings)  Poorly Graded Sand with Silt  (SP‐SM) with interbedded  layers Clay (CL)  0.4 inches/hour  I‐2  Double Ring   Infiltrometer  (12” and 24”  Rings)  Poorly Graded Sand with Silt  (SP‐SM) with interbedded  layers of Clay (CL)  0.6 inches/hour  I‐3  Double Ring   Infiltrometer  (12” and 24”  Rings)  Poorly Graded Sand with Silt  (SP‐SM)  2.4 inches/hour  *Field Values, no factor of safety applied. Typical factors of safety range from 3 to 10 depending on the type of  system which will be designed using the field values and depending on the level of pre‐treatment and influent to be  discharged into the basins per Riverside County BMP Design Manual.  Infiltration Conclusions and Recommendations: Based upon our infiltration tests results and  evaluation of the 2016 field boring logs, it is our opinion that silt and/or clay lenses or laminations  are causing reduced infiltration rates in otherwise highly permeable sandy type soil. A review of  the soil profile logs (Earth Systems, 2016) indicate several profiles show these silt and/or clay  layers or lenses to depths of 10 to 12 feet, but on occasions some extend to a depth of 20 feet  below the ground surface (bgs).  Infiltration testing (I‐1, I‐2, and I‐3) indicate infiltration rates of  0.4, 0.6, and 2.4 inches/hour before being factored. General recommendations are presented as  follows:   It is our opinion that for the bottom of the retention basin without removal of the silt and  clay layers/lenses/laminates, an average before‐factored infiltration rate using 0.4  inches/hour should be used for design purposes.   It is our opinion that for the bottom of the retention basin with removal of the silt and  clay layers/lenses/laminates, (to a depth determined by the Civil Engineer) below the  bottom of the basin, an average before‐factored infiltration rate using 2.4 inches/hour  should be used for design purposes.   It is our opinion that dual chamber type drywells having a minimum of 10 feet of  embedment into Sandy soil (see attached boring logs) may be needed to provide more  reliable infiltration along with the consideration of the retention basin bottom’s  infiltration rate.    In addition to founding basins in sandy soil, borings placed in a grid pattern (minimum 3  feet center to center, 8” diameter, 10 feet deep and backfill with clean sand) that  March 30, 2017 7 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  penetrate through silt and clay lenses, layers, or laminations could be used below the  infiltrating basin bottom elevation to increase infiltration rates (to 2.4 inches/hr) in areas  of clayey or silty soils.    If drywells are used, the should be located as far as practical from building structures (at  least 30 feet).    If drywells are used, their shafts (sides and bottoms) should be provided with geofabric  designed to prevent soil migration between two different soils’ or the soil and gravel  interface.  Backfill should be separated from native soils by a geofabric such as Mirafi  140N or direct equivalent.    Gravel backfill may consist of 3/8” pea‐gravel or ¾ inch open (gap) graded crushed rock  as other material approved by the geotechnical engineer.  When calculating volumes,  areas filled with gravel backfill may be considered to have a void ratio of 0.40 (40%).   Nuisance water from landscape irrigation or other runoff associated with daily activities  will saturate the soils in the basins and they will not infiltrate in an expedient manner if  needed during a storm event. Nuisance water should be controlled and conveyed  appropriately by the civil designer.   The project geotechnical report and previously provided design information should be  referred to for other design recommendations.  The previously provided design  information was in a plan review regarding uplift forces on the nearby channel lining due  to water pressure and erosion of site soils (Earth Systems plan review to Greg Saia in  December 2016).    Maintenance of drainage systems and infiltration structures can be the most critical  element in determining the success of a design.  They must be protected and maintained  from sediment and oil‐laden water both during and after construction to prevent clogging  of the surficial soils and filter medium.  The potential for clogging can be reduced by pre‐ treating structure inflow through the installation of maintainable forebays, oil traps,  biofilters, or sedimentation chambers.  In addition, sediment, leaves, and debris must be  removed from inlets and traps on a regular basis.  Since these and other factors (such as  varying soil conditions) may affect the rate of water infiltration, it should be considered  to apply a conservative factor of safety [FOS] to the unfactored Basic Infiltration Rates  presented within to provide a reliable basis for design.  In order to account not only for  the unknown factors above but also for changes of conditions during the use of the  structures such as potential clogging effects due to washing in of soil fines, a FOS between  3 and 10 should be applied in the design as recommended in the Riverside County  Stormwater Quality Design Handbook, 2006 and/or Riverside County Flood Control, 2011.   The factor of safety should be selected by the project drainage engineer and may be  dependent on agency guidelines and the presence of filters and sedimentation structures.   If these measures are provided, the factor of safety can be reduced.    The drainage pattern should be established at the time of final grading and maintained  throughout the life of the project.  Additionally, drainage structures should be maintained  (including the de‐clogging of piping, bottom cleaning, bottom silt removal, etc.)  March 30, 2017 8 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  throughout their design life. Maintenance of these structures should be incorporated into  the project plans and site operations and maintenance documents.   It is expected that retention bottom soils will be graded with heavy, construction grade  earth moving equipment which can compact soils during grading.  Compacted soils have  a reduced inability to infiltrate water.  As such, we recommend leaving retention basin  bottom soils in a native, undisturbed or scarified condition to maintain infiltration rates.   Basin bottoms should not be founded in clayey or silty soils.  Where these soils are  encountered in the basin bottom, the basin should be deepened to penetrate through  the clay or silt soils or the boring or drywell methods discussed earlier be implemented to  provide additional infiltration.   March 30, 2017 9 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Section 3   LIMITATIONS AND ADDITIONAL SERVICES  3.1 Uniformity of Conditions and Limitations  Our findings and recommendations in this report are based on selected points of field  exploration, laboratory testing, and our understanding of the proposed project.  Conditions will  vary between or beyond the points explored.  The nature and extent of these variations may not  become evident until construction.  Variations in soil or groundwater may require additional  studies, consultation, and possible revisions to our recommendations.  Final grading and foundation plans were not available for our review prior to the preparation of  this report, and therefore, the recommendations presented within may change pending a review  of the final grading plans.  Recommendations presented in this report should not be extrapolated  to other areas or be used for other projects without our prior review.  The planning and construction process is an integral design component with respect to the  geotechnical aspects of this project.  Because geotechnical engineering is an inexact science due  to the variability of natural processes and because we sample only a small portion of the soil and  material affecting the performance of the proposed structure, unanticipated or changed  conditions can be disclosed during demolition and construction.  Proper geotechnical  observation and testing during construction is imperative to allow the geotechnical engineer the  opportunity to verify assumptions made during the design process and to verify that our  geotechnical recommendations have been properly interpreted and implemented during  construction.  Therefore, we recommend that Earth Systems be retained during the construction  of the proposed improvements to observe compliance with the design concepts and geotechnical  recommendations, and to allow design changes in the event that subsurface conditions or  methods of construction differ from those assumed while completing this commission.  If we are  not accorded the privilege of performing this review, we can assume no responsibility for  misinterpretation of our recommendations.  The above services can be provided in accordance  with our current Fee Schedule.  Our evaluation of subsurface conditions at the site has considered subgrade soil and groundwater  conditions present at the time of our study.  The influence(s) of post‐construction changes to  these conditions such as introduction or removal of water into or from the subsurface will likely  influence future performance of the proposed project.  It should be recognized that definition  and evaluation of subsurface conditions are difficult. Judgments leading to conclusions and  recommendations are generally made with incomplete knowledge of the subsurface conditions  due to the limitation of data from field studies. The availability and broadening of knowledge and  professional standards applicable to engineering services are continually evolving.    As such, our services are intended to provide the Client with a source of professional advice,  opinions and recommendations based on the information available as applicable to the project  location, time of our services, and scope. If the scope of the proposed construction changes from  that described in this report, the conclusions and recommendations contained in this report are  not considered valid unless the changes are reviewed, and the conclusions of this report are  modified or approved in writing by Earth Systems.    March 30, 2017 10 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Findings of this report are valid as of the issued date of the report.  However, changes in  conditions of a property can occur with passage of time, whether they are from natural processes  or works of man, on this or adjoining properties.  In addition, changes in applicable standards  occur, whether they result from legislation or broadening of knowledge.  Accordingly, findings of  this report may be invalidated wholly or partially by changes outside our control.  Therefore, this  report is subject to review and should not be relied upon after a period of one year.  This report is issued with the understanding that the owner or the owner’s representative has  the responsibility to bring the information and recommendations contained herein to the  attention of the architect and engineers for the project so that they are incorporated into the  plans and specifications for the project.  The owner or the owner’s representative also has the  responsibility to verify that the general contractor and all subcontractors follow such  recommendations.  It is further understood that the owner or the owner’s representative is  responsible for submittal of this report to the appropriate governing agencies.  As the Geotechnical Engineer of Record for this project, Earth Systems has striven to provide our  services in accordance with generally accepted geotechnical engineering practices in this locality  at this time.  No warranty or guarantee, express or implied, is made.  This report was prepared  for the exclusive use of the Client and the Client’s authorized agents.  Earth Systems should be provided the opportunity for a general review of final design and  specifications in order that earthwork and foundation recommendations may be properly  interpreted and implemented in the design and specifications.  If Earth Systems is not accorded  the privilege of making this recommended review, we can assume no responsibility for  misinterpretation or applicability of our recommendations.  The owner or the owner’s  representative has the responsibility to provide the final plans requiring review to Earth Systems’  attention so that we may perform our review.    Any party other than the client who wishes to use this report shall notify Earth Systems of such  intended use.  Based on the intended use of the report, Earth Systems may require that additional  work be performed and that an updated report be issued.  Non‐compliance with any of these  requirements by the client or anyone else will release Earth Systems from any liability resulting  from the use of this report by any unauthorized party.  Although available through Earth Systems, the current scope of our services does not include an  environmental assessment or an investigation for the presence or absence of wetlands,  hazardous or toxic materials in the soil, surface water, groundwater, or air on, below, or adjacent  to the subject property.    3.2 Additional Services  This report is based on the assumption that a program of client consultation, construction  monitoring, and testing will be performed during the final design and construction phases to  check compliance with these recommendations.  Maintaining Earth Systems as the geotechnical  consultant from beginning to end of the project will provide continuity of services.  The  geotechnical engineering firm providing tests and observations shall assume the responsibility of  Geotechnical Engineer of Record.  March 30, 2017 11 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  Construction monitoring and testing would be additional services provided by our firm.  The costs  of these services are not included in our present fee arrangements, but can be obtained from our  office.  The recommended review, tests, and observations include, but are not necessarily limited  to the following:   Consultation during the final design stages of the project.   A review of the building and grading plans to observe that recommendations of our report  have been properly implemented into the design.   Observation and testing during site preparation, grading, and placement of engineered fill.   Special Inspection for concrete, masonry, steel during construction.   Consultation as needed during construction.  ‐o0o‐  Appendices as cited are attached and complete this report.  March 30, 2017 12 File No.: 12426‐02    Doc. No.: 17‐03‐716    EARTH SYSTEMS GLOBAL  REFERENCES  American Society for Testing Materials, 2016, Annual Book of Standards.  Earth Systems Southwest, 2016, Geotechnical Engineering Report, 73‐450 & 73‐500 Dinah Shore  Drive, Palm Desert, Riverside County, California, dated December 7, 2016, File No.: 12426‐ 02, Doc No.: 16‐12‐701.  Riverside County, 2006, Stormwater Quality Best Management Practice Design Handbook, July  21, 2006.  Riverside County Flood Control Water Conservation District, 2011, Design Handbook for Low  Impact Development Best Management Practices, September, 2011.          EARTH SYSTEMS GLOBAL  APPENDIX A  Plate 1 – Site Location Map  Plate 2 – Infiltration Test Location Map  Plate 3 – Project Soils Report Boring Location Map  Terms and Symbols Used on Boring Logs  Soil Classification System  Logs of Borings 4, 8, 9, 10, and 17 (Earth Systems, 2016)  Proposed Automotive Dealership Site 73-450 & 73-500 Dinah Shore Drive Palm Desert, Riverside County, California File No.: 12426-023/30/2017 Plate 1 Site Location Map Approximate Site Location LEGEND Approximate Scale: 1" = 850’ 0 850’1,700’ Source: Google Earth satellite image dated 7/14/2016. 10 F r ee w ay 10 F r ee w ay Dinah Shore DriveDinah Shore Drive Monterey AvenueMonterey AvenueGateway DriveGateway DriveApproximate Site Location Approximate Site Location Earth Systems Global 3/30/2017 Plate 2 Infiltration Test Locations Proposed Automotive Dealership Site 73-450 & 73-500 Dinah Shore Drive Palm Desert, Riverside County, California File No.: 12426-02 Earth Systems Southwest Approximate Scale: 1" = 65’ 0 65’130’ LEGEND Approximate Infiltration Test Locations I-1 I-2 I-3 I-3 Source: Centerpoint Integrated Solutions Preliminary Grading Plan, Sheet C5.0 dated 12/21/16. @A @A @A @A @A @A @A @A @A @A @A@A@A@A@A@A@A@A@A @A @A @A @A @A @A @A @A @A @A @A B-9B-8B-7 B-6B-5 B-4B-3B-2 B-1 B-30 B-29 B-28B-27B-26B-25B-24B-23B-22 B-21 B-20 B-19 B-18 B-17 B-16 B-15 B-14 B-13 B-12 B-11 B-10 116.38194° W 116.38194° W 116.38333° W 116.38333° W 116.38472° W33.80139° N33.8° N33.80139° N @A @A @A @A @A @A @A @A @A @A @A@A@A@A@A@A@A@A@A @A @A @A @A @A @A @A @A @A @A @A B-9B-8B-7 B-6B-5 B-4B-3B-2 B-1 B-30 B-29 B-28B-27B-26B-25B-24B-23B-22 B-21 B-20 B-19 B-18 B-17 B-16 B-15 B-14 B-13 B-12 B-11 B-10 116.38194° W 116.38194° W 116.38333° W 116.38333° W 116.38472° W33.80139° N33.8° N33.80139° N 0 60 120 180 240 30030 Feet I 3/30/2017 Plate 3 Previous Boring Locations Proposed Automotive Dealership Site 73-450 & 73-500 Dinah Shore Drive Palm Desert, Riverside County, California File No.: 12426-02 LEGEND @A Proposed Boring Locations Earth Systems Southwest AA BB CC 11 22 33 44 55 66 77 88 99 1010 Test_No Lat_Lon_NAD83 B-1 33.80172N,116.38356W B-2 33.8017N,116.38322W B-3 33.80154N,116.38294W B-4 33.80139N,116.38267W B-5 33.80123N,116.3824W B-6 33.80108N,116.38215W B-7 33.80092N,116.38187W B-8 33.80077N,116.3816W B-9 33.80061N,116.38134W B-10 33.80045N,116.38107W B-11 33.80023N,116.38126W B-12 33.80038N,116.38152W B-13 33.80054N,116.38179W B-14 33.80069N,116.38205W B-15 33.80085N,116.38232W Te st_No Lat_Lon_NAD83 B-16 33.80101N,116.3826W B-17 33.80116N,116.38286W B-18 33.80132N,116.38314W B-19 33.80148N,116.38341W B-20 33.80155N,116.3837W B-21 33.80138N,116.38384W B-22 33.80128N,116.38359W B-23 33.80112N,116.3833W B-24 33.80096N,116.38303W B-25 33.80081N,116.38277W B-26 33.80065N,116.3825W B-27 33.80049N,116.38223W B-28 33.80032N,116.382W B-29 33.8001N,116.38175W B-30 33.79992N,116.3816W Dinah S h o r e Drive Dinah S h o r e Drive Qal/QsQal/Qs - Alluvial and Wind Deposited Soils GEOLOGIC SYMBOL Qal/QsQal/Qs Qal/QsQal/Qs Terms and Symbols Used on Boring Logs Earth Systems Southwest DESCRIPTION FIELD TEST A 1/8 in. (3-mm) thread cannot be rolled at any moisture content. Nonplastic PLASTICITY Low Medium High The thread can barely be rolled. The thread is easy to roll and not much time is required to reach the plastic limit. The thread can be rerolled several times after reaching the plastic limit. MOISTURE CONDITION Dry.....................Absence of moisture, dusty, dry to the touch Damp................Slight indication of moisture Moist.................Color change with short period of air exposure (granular soil) Below optimum moisture content (cohesive soil) Wet....................High degree of saturation by visual and touch (granular soil) Above optimum moisture content (cohesive soil) Saturated..........Free surface water RELATIVE PROPORTIONS Trace.............minor amount (<5%) with/some......significant amount modifier/and...sufficient amount to influence material behavior (Typically >30%) Moisture Condition: Moisture Content: Dry Density: An observational term; dry, damp, moist, wet, saturated. The weight of water in a sample divided by the weight of dry soil in the soil sample expressed as a percentage. The pounds of dry soil in a cubic foot. MOISTURE DENSITY Very Soft Soft Medium Stiff Stiff Very Stiff Hard *N=0-1 N=2-4 N=5-8 N=9-15 N=16-30 N>30 *C=0-250 psf C=250-500 psf C=500-1000 psf C=1000-2000 psf C=2000-4000 psf C>4000 Squeezes between fingers Easily molded by finger pressure Molded by strong finger pressure Dented by strong finger pressure Dented slightly by finger pressure Dented slightly by a pencil point or thumbnail CONSISTENCY OF COHESIVE SOILS (CLAY OR CLAYEY SOILS) Very Loose Loose Medium Dense Dense Very Dense *N=0-4 N=5-10 N=11-30 N=31-50 N>50 RD=0-30 RD=30-50 RD=50-70 RD=70-90 RD=90-100 Easily push a 1/2-inch reinforcing rod by hand Push a 1/2-inch reinforcing rod by hand Easily drive a 1/2-inch reinforcing rod with hammer Drive a 1/2-inch reinforcing rod 1 foot with difficulty by a hammer Drive a 1/2-inch reinforcing rod a few inches with hammer *N=Blows per foot in the Standard Penetration Test at 60% theoretical energy. For the 3-inch diameter Modified California sampler,140-pound weight, multiply the blow count by 0.63 (about 2/3) to estimate N. If automatic hammer is used, multiply a factor of 1.3 to 1.5 to estimate N. RD=Relative Density (%). C=Undrained shear strength (cohesion). RELATIVE DENSITY OF GRANULAR SOILS (GRAVELS, SANDS, AND NON-PLASTIC SILTS) SOIL GRAIN SIZE 12”3”3/4”4 10 40 200 305 76.2 19.1 4.76 2.00 0.42 0.074 0.002 SOIL GRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE COARSE FINEBOULDERSCOBBLES GRAVEL SAND COARSE MEDIUM FINE SILT CLAY Soil classification is based on ASTM Designations D 2487 and D 2488 (Unified Soil Classification System). Information on each boring log is a compilation of subsurface conditions obtained from the field as well as from laboratory testing of selected samples. The indicated boundaries between strata on the boring logs are approximate only and may be transitional. DESCRIPTIVE SOIL CLASSIFICATION LOG KEY SYMBOLS Bulk, Bag or Grab Sample Standard Penetration Split Spoon Sampler (2” outside diameter) Modified California Sampler (3” outside diameter) No Recovery GROUNDWATER LEVEL Water Level (measured or after drilling) Water Level (during drilling) Soil Classification System Earth Systems Southwest MAJOR DIVISIONS GRAPHIC SYMBOL LETTER SYMBOL TYPICAL DESCRIPTIONS COARSE GRAINED SOILS FINE-GRAINED SOILS GRAVEL AND GRAVELLY SOILS SAND AND SANDY SOILS SILTS AND CLAYS CLEAN GRAVELS GRAVELS WITH FINES CLEAN SAND (Little or no fines) SAND WITH FINES (appreciable amount of fines) LIQUID LIMIT THAN 50LESS LIQUID LIMIT THAN 50 GREATER HIGHLY ORGANIC SOILS VARIOUS SOILS AND MAN MADE MATERIALS MAN MADE MATERIALS PT GW GP GM GC SW SP SM SC ML CL OL MH CH OH Well-graded gravels, gravel-sand mixtures, little or no fines Poorly-graded gravels, gravel-sand mixtures. Little or no fines Silty gravels, gravel-sand-silt mixtures Clayey gravels, gravel-sand-clay mixtures More than 50% of material is than No. 200 sieve size larger More than 50% of material is than No. 200 sieve size smaller More than 50% of coarse fraction No. 4 sievepassing Well-graded sands, gravelly sands, little or no fines Poorly-graded sands, gravelly sands, little or no fines Silty sands, sand-silt mixtures Clayey sands, sand-clay mixtures Inorganic silts and very fine sands, rock flour, silty low clayey fine sands or clayey silts with slight plasticity Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays Organic silts and organic silty clays of low plasticity Inorganic silty, micaceous, or diatomaceous fine sand or silty soils Inorganic clays of high plasticity, fat clays Organic clays of medium to high plasticity, organic silts Peat, humus, swamp soils with high organic contents Fill Materials Asphalt and concrete More than 50% of coarse fraction on No. 4 sieve retained 0 5 10 15 20 25 30 35 40 45 50 55 60 Boring No. Project Name Project Number: Boring Location: Drilling Method:Depth (Ft.)Sample Type Penetration Resistance (Blows/6")SymbolUSCSDry DensityPage 1 of 1 Drilling Date: Drill Type: Logged By:BulkSPTMOD Calif.Description of Units (pcf)MoistureContent (%)Note: The stratification lines shown represent the approximate boundary between soil and/or rock types and the transition may be gradational. Blow Dry Graphic Trend Earth Systems *OREDO Count Density Boring completed at 20 feet No groundwater encountered Backfill with cuttings POORLY GRADED SAND WITH SILT: light gray brown, medium dense, damp, fine grained sand SILTY SAND: gray, medium dense, damp, fine grained sand POORLY GRADED SAND WITH SILT: yellow brown, medium dense, damp, fine grained sand 2 2 106 95 SP-SM SM SP-SM 8, 10, 11 5, 6, 9 3, 6, 9 3, 6, 10 B-4 Proposed Automotive Dealership 12426-02 See Plate A-2 November 16, 2016 8" HSA Mobile B61 w/Autohammer R. Howe 79-811B Country Club Drive, Bermuda Dunes, Ca 92203 Phone (760) 345-1588, Fax (760) 345-7315 0 5 10 15 20 25 30 35 40 45 50 55 60 Boring No. Project Name Project Number: Boring Location: Drilling Method:Depth (Ft.)Sample Type Penetration Resistance (Blows/6")SymbolUSCSDry DensityPage 1 of 1 Drilling Date: Drill Type: Logged By:BulkSPTMOD Calif.Description of Units (pcf)MoistureContent (%)Note: The stratification lines shown represent the approximate boundary between soil and/or rock types and the transition may be gradational. Blow Dry Graphic Trend Earth Systems *OREDO Count Density Boring completed at 21-1/2 feet No groundwater encountered Backfill with cuttings brown POORLY GRADED SAND WITH SILT: yellow brown, loose, damp, fine to medium grained sand SILTY SAND: yellow brown to gray brown, medium dense, damp, fine to medium grained sand POORLY GRADED SAND WITH SILT: dark gray brown, medium dense, moist, fine grained sand POORLY GRADED SAND: yellow brown, medium dense, moist, fine grained sand POORLY GRADED SAND WITH SILT: light gray brown, dense, damp, fine grained sand POORLY GRADED SAND: gray brown, dense, damp, fine grained sand 4 4 4 3 6 2 2 98 105 100 123 97 113 108 SP-SM SM SP-SM SP SP-SM SP 5,6,7 4,6,7 4,5,9 3,5,10 5,6,8 5,9,14 6,9,14 B-8 Proposed Automotive Dealership 12426-02 See Plate A-2 November 15, 2016 8" HSA Mobile B61 w/Autohammer R. Howe 79-811B Country Club Drive, Bermuda Dunes, Ca 92203 Phone (760) 345-1588, Fax (760) 345-7315 0 5 10 15 20 25 30 35 40 45 50 55 60 Boring No. Project Name Project Number: Boring Location: Drilling Method:Depth (Ft.)Sample Type Penetration Resistance (Blows/6")SymbolUSCSDry DensityPage 1 of 1 Drilling Date: Drill Type: Logged By:BulkSPTMOD Calif.Description of Units (pcf)MoistureContent (%)Note: The stratification lines shown represent the approximate boundary between soil and/or rock types and the transition may be gradational. Blow Dry Graphic Trend Earth Systems *OREDO Count Density Boring completed at 21-1/2 feet No groundwater encountered Backfill with cuttings POORLY GRADED SAND WITH SILT: yellow brown, medium dense, dry, fine grained sand SILTY SAND: yellow brown to brown, medium dense, damp, interbedded lenses of CL and SP-SM POORLY GRADED SAND WITH SILT: light gray brown, loose, damp, fine grained sand, some ML lenses in sampler tip <1/2" POORLY GRADED SAND: yellow brown, loose, damp, fine to medium grained sand POORLY GRADED SAND WITH SILT: brown, damp, fine grained sand, SM lenses POORLY GRADED SAND: yellow brown, medium dense, moist, fine to medium grained sand 2111 SP-SM SM SP-SM SP SP-SM SP 6, 10, 12 8, 10, 12 3, 5, 7 4, 4, 10 4, 8, 14 B-9 Proposed Automotive Dealership 12426-02 See Plate A-2 November 16, 2016 8" HSA Mobile B61 w/Autohammer R. Howe 79-811B Country Club Drive, Bermuda Dunes, Ca 92203 Phone (760) 345-1588, Fax (760) 345-7315 0 5 10 15 20 25 30 35 40 45 50 55 60 Boring No. Project Name Project Number: Boring Location: Drilling Method:Depth (Ft.)Sample Type Penetration Resistance (Blows/6")SymbolUSCSDry DensityPage 1 of 1 Drilling Date: Drill Type: Logged By:BulkSPTMOD Calif.Description of Units (pcf)MoistureContent (%)Note: The stratification lines shown represent the approximate boundary between soil and/or rock types and the transition may be gradational. Blow Dry Graphic Trend Earth Systems *OREDO Count Density Boring completed at 20 feet No groundwater encountered Backfill with cuttings SILTY SAND: gray brown, medium dense, dry, fine grained sand POORLY GRADED SAND WITH SILT: yellow brown, medium dense, damp, fine grained sand, some thin clay lenses SILTY SAND: gray brown, loose, damp, fine grained sand POORLY GRADED SAND WITH SILT: yellow brown, loose, damp, fine grained sand POORLY GRADED SAND WITH SILT: brown, damp, fine grained sand 1109 SM SP-SM SM SP-SM SP-SM 7, 10, 10 6, 9, 12 3, 5, 7 3, 6, 8 B-10 Proposed Automotive Dealership 12426-02 See Plate A-2 November 16, 2016 8" HSA Mobile B61 w/Autohammer R. Howe 79-811B Country Club Drive, Bermuda Dunes, Ca 92203 Phone (760) 345-1588, Fax (760) 345-7315 0 5 10 15 20 25 30 35 40 45 50 55 60 Boring No. Project Name Project Number: Boring Location: Drilling Method:Depth (Ft.)Sample Type Penetration Resistance (Blows/6")SymbolUSCSDry DensityPage 1 of 1 Drilling Date: Drill Type: Logged By:BulkSPTMOD Calif.Description of Units (pcf)MoistureContent (%)Note: The stratification lines shown represent the approximate boundary between soil and/or rock types and the transition may be gradational. Blow Dry Graphic Trend Earth Systems *OREDO Count Density Boring completed at 20 feet No groundwater encountered Backfill with cuttings POORLY GRADED SAND WITH SILT: yellow brown, medium dense, dry, fine grained sand SILT: brown, stiff, dry POORLY GRADED SAND WITH SILT: yellow brown to gray brown, medium dense, damp, fine grained sand POORLY GRADED SAND: light gray, medium dense, damp, fine grained sand POORLY GRADED SAND WITH SILT: brown, damp, fine grained sand 1106 SP-SM ML SP-SM SP SP-SM 6, 8, 12 7, 9, 11 6, 8, 10 4, 8, 12 B-17 Proposed Automotive Dealership 12426-02 See Plate A-2 November 16, 2016 8" HSA Mobile B61 w/Autohammer R. Howe 79-811B Country Club Drive, Bermuda Dunes, Ca 92203 Phone (760) 345-1588, Fax (760) 345-7315 6.85 3/8/2022 6 KTM 3 Sand 0 to 6.85 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 5.22 6.8 18.96 2 25 3.85 6.8 35.4 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 3.40 6.45 36.60 0.27 2 10 3.60 6.12 30.24 0.33 3 10 2.40 5.63 38.76 0.26 4 10 3.13 5.50 28.44 0.35 5 10 2.00 5.32 39.84 0.25 6 10 2.54 5.19 31.80 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 67.78 76.19 64.82 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 113.19 90.64 83.02 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-1 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 64.820.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.51 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  6.75 3/8/2022 6 KTM 3 Sand 0 to 6.75 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 3.6 6.6 36 2 25 2.8 6.6 45.6 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 2.32 5.30 35.76 0.28 2 10 2.68 5.10 29.04 0.34 3 10 2.10 4.82 32.64 0.31 4 10 2.70 4.94 26.88 0.37 5 10 2.43 5.05 31.44 0.32 6 10 2.30 4.99 32.28 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 55.78 63.58 63.36 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 73.97 61.68 60.59 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-2 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 63.360.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.38 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix F Structural BMP/Retention Facility Sizing Calculations & Design Details CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Preliminary Hydrology and Hydraulics Study, July 2022 CarMax – Store No. [6113] Drainage Study, 2017 Revision History Date Comment CARMAX AUTO SUPERSTORE NO. 6113 BUILDING/PARKING LOT EXPANSION AND CARWASH ADDITION PRELIMINARY HYDROLOGY AND HYDRAULICS STUDY CITY OF PALM DESERT Date: August 2022 Prepared for: CarMax Auto Superstores, Inc. 12800 Tuckahoe Creek Parkway Richmond, VA 23238 Telephone: (804) 747-0422 x 4237 Report Prepared By: Michael Baker International 75-410 Gerald Ford Drive, Suite 100 Engineer of Work/ Contact Person: Palm Desert, CA. 92211 Todd Pitner, P.E. Telephone: (760) 346-7481 Danielle Peltier, EIT MBI JN: 190260 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 SECTION 1 – INTRODUCTION 1.1 BACKGROUND Michael Baker International has been retained by CarMax Auto Superstores, Inc. to prepare a preliminary engineering design for the CarMax Auto Superstore Building/Parking Lot Expansion and Carwash Addition located at 73-450 Dinah Shore Drive in Palm Desert, CA 92211. This report shows how stormwater runoff from the 100-year storm event shall be handled on-site for proper storm water handling, preventing negative impacts to public drainage facilities and local water resources. The project site is about 300 feet northwest of the intersection at Dinah Shore Drive and Gateway Drive. Figure 1 below shows the general vicinity of the project location. The approximate 2-acre site is on a vacant, undeveloped lot northwest of the existing store parking lot. The property currently lies within a FEMA mapped flood plain Zone X, areas determined to be outside the 0.2% annual chance floodplain (Appendix A). Runoff from the proposed development will be collected in storm drain facilities and directed to an underground retention basin in which overflow will drain into an existing, offsite channel adjacent to the property that ultimately discharges to a regional retention basin that is located about 0.75 mi southeast of the project. The channel and regional basin are owned, operated, maintained, and improved by the City of Palm Desert. Reference maps are available in Appendix B. Figure 1. Vicinity Map Figure 2. Retention Basin in Relation to Project Site MID-VALLEY CHANNEL REGIONAL RETENTION BASIN PROJECT SITE www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 1.2 OBJECTIVE The objective of this report is to determine the 100-year on-site discharges in accordance with the criteria and procedures described the Riverside County Flood Control & Water Conservation District (RCFCD&WCD) Hydrology Manual. The calculations included in this report have been prepared to show the required storage volume for on-site retention determined by the 100-year, 24-hour storm event. As of June 15, 2009, developers must comply with the Colorado River Basin Regional Water Quality Control Board (CRBRWCB) requiring the preparation, approval, and implementation of a project-specific WQMP for discretionary New Developments and Redevelopment projects that fall into one (1) of the eight (8) priority development project categories. This project falls into category 8; “Parking lots of 5,000 square feet or more or with 25 or more parking spaces and potentially exposed to Urban Runoff”. A separate submittal will be made for the final project-specific WQMP. SECTION 2 – PROJECT DESCRIPTION 2.1 EXISTING CONDITIONS The proposed project site is located northwest of the existing CarMax store and consists of an undeveloped lot with poor land cover with an existing access driveway. The proposed project will also include minor improvements to the existing store. The CarMax property consists of Parcels A and B which can be seen below in Figure 3. The existing store and its associated parking lots are located on Parcel A, which utilizes an above ground infiltration basin located on the southeast corner of the property. The street-fronting landscaped area of the property is a Self-Treating Area (STA) in which runoff sheet flows into public drainage facilities in Dinah Shore Drive. Landscape adjacent to the Mid-Valley Channel is also a separate STA that drains offsite to the channel. Runoff from the remaining landscape, parking lots and building sheet flows into gutters that lead to the private infiltration basin. When the retention basin is filled to capacity, an overflow weir allows stormwater to drain into the City owned, operated, maintained, and improved storm water channel located northeast of, and adjacent to, the site. There is no stormwater run-on from neighboring land. PARCEL B PARCEL A Figure 3. Parcel Distinction www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 The runoff of the undeveloped land on Parcel B flows from the high point at the northwest end of the lot, outwards toward the perimeter of the property. The runoff has three discharge points: the existing CarMax, Dinah Shore Drive, and the Mid-Valley Channel. Reference the Existing Condition Hydrology Exhibit in Appendix C for further details. 2.2 PROPOSED CONDITIONS The proposed development will include a 2,351 square feet expansion of the existing CarMax Superstore building, the construction of a 923 square feet carwash, and extension of the parking lot on the northwest end of Parcel A onto Parcel B. Demolition of the access driveway will make way for construction of an asphalt sales area on Parcel B. Landscape areas will be added along the perimeter of Parcel B similar to the existing development layout on Parcel A. The changes occurring on Parcel A will integrate with the current flow patterns; sheet flow into gutters that lead to the private retention basin. The proposed developments on Parcel A will replace impervious asphalt with impervious building, resulting in negligible changes in runoff volumes. Underground retention chambers will be used to capture runoff from the development of Parcel B, overflow will be directed to the adjacent Mid-Valley Channel. The drainage management areas (DMAs) will include the paved areas on Parcel B and a portion of the proposed landscape. The runoff from the proposed sales area flows in the eastern direction towards the three underground chambers’ inlets. One of the inlets will capture runoff only from the southeastern corner of the proposed sales staging area. The two larger of the three are located at the low point of the parcel and receive runoff from the majority of the project site; one receives runoff from the new sales staging area and the other from the parking lot extension. Runoff from the landscape area included in the DMA will flow in the northeast direction, joined by runoff from the adjacent parking lot extension that flows in the northern direction, and into a gutter that directs runoff to the catch basin inlet. The remaining landscape areas will be STAs. A STA is an area within a project site that does not drain to a site design Best Management Practice (BMP) but drains directly offsite or to the MS4, rather than having its runoff comingle with runoff from the impervious surfaces. The STAs were excluded from the sizing of the underground basin. The landscape on the west end of the parcel will have runoff flow onto Dinah Shore Drive, joining public drainage facilities. Runoff from the remaining landscape on the northern perimeter will follow existing flow patterns: flow outwards from the property onto City owned land that discharges into the Mid-Valley Channel. Landscape on the northeastern perimeter will do the same, however, this area is closer to the storm channel and will travel a short distance to discharge into the Mid-Valley Channel. The Hydrology Exhibit of the Post-Development Conditions can be found in Appendix C. SECTION 3 – HYDROLOGY 3.1 APPROACH AND METHODOLOGY The hydrologic analysis described in this report was performed in accordance with the criteria and procedures outlined in the Riverside County Flood Control and Water Conservation District Hydrology Manual dated April 1978, referred to hereafter as “Hydrology Manual”. Hydrologic calculations to evaluate surface runoff associated with the 100-year storm event were performed using data from the Web Soil Survey and NOAA Atlas Point Precipitation Frequency Estimates to find soil classification and rainfall intensity values. The Web Soil www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 use is shown below in Table 1. Watershed losses generally consist of infiltration, depression storage, vegetation, and minor amounts of evaporation. Loss rates vary with each land use and soil type. The procedures and criteria used in this study for estimating loss rates follow the guidelines of the Hydrology Manual. The Antecedent Moisture Condition (AMC) indicates the soil wetness prior to a particular storm and the runoff potential for the subject storm. An AMC is defined as: AMC I: Lowest runoff potential AMC II: Moderate runoff potential AMC III: Highest runoff potential AMC II was applied for the 100-year storm event as outlined in the Hydrology Manual. 3.2 STORAGE VOLUMES The project site is part of a Hydrology Study done in 2002 for Monterey 170 LLC Parcel Map No. 24255 in which the City of Palm Desert proposed a retention basin for the incremental increase in runoff, due to development, for the 100-year 24-hour storm. In 2006 another Hydrology Study for Palm Desert Assessment District 2004-02 was done for 330 acres south of the site to address the same conditions as PM 24255, and the existing master retention basin located at the northeast corner of Parcel Map No. 24255 was made larger. The existing retention basin is a long rectangular basin with 1.5:1 side slopes and Geo-Web material to maintain slope stability and allow percolation during and after storms (a percolation rate of 2 inches per hour was used in the calculations). A successive report from 2005, Retention Basin for Palm Desert Assessment District 2004-02 combined with Parcel Map No. 24255 (Monterey 170), was approved detailing the total incremental increase in runoff, due to development, for the 100-year, 24-hour storm for the total tributary area bounded on the west by Monterey Avenue, on the north by the railroad tracks, on the east by Portola Avenue, and on the south by Gerald Ford Drive. Per the Palm Desert Municipal Code, developments, or redevelopments, of one acre or more in size shall be designed to retain the stormwater from a 100-year, 24-hour duration storm on-site, therefore the proposed building and parking lot expansion will retain the existing condition 100-year, 24-hour storm on-site. The local ordinance requirement will be satisfied with the combined retention of the existing condition 100-year 24-hour storm on-site and the retention of runoff from the developed conditions in the regional retention basin. A spreadsheet based on the shortcut method synthetic unit hydrograph approach as Table 1 - WQMP Land-Use Summary Area Asphalt Concrete Building Landscape % Impervious % Pervious Sq-ft Acres Sq-ft Sq-ft Sq-ft Sq-ft 71.94 28.06 94,359 2.17 61,712 2,893 3,274 26,479 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 100-year 24-hour storm on-site and the retention of runoff from the developed conditions in the regional retention basin. A spreadsheet based on the shortcut method synthetic unit hydrograph approach as prescribed by the Hydrology Manual has been utilized to perform the calculations. Basin storage capacity is modeled based on the “truncated pyramid” formula, a more conservative estimate than “averaged end areas” sometimes used. Rainfall input data for the 100-year, 24- hour storm is input per said Hydrology Manual. Basin Inflow is modeled in 15-minute intervals for the 24-hour storm, based on the design storm unit hydrographs presented in the manual. The full calculations can be found in the Synthetic Unit Hydrograph Calculations Section of this Report in Appendix E. The 100-year, 24-hour storm yields a maximum volume of approximately 6,213 cubic feet. The proposed underground retention chamber system has a capacity of approximately 6,448 cubic feet. The determined area of the top and bottom of the retention basin is approximately 1,969 square feet. The maximum depth of the retention basin design on the Unit Hydrograph calculations was edited to have the maximum storage match the installed design volume to ensure accurate calculations of the basin storage. The edit is needed to show the actual volume of the chambers that does not include the depth of the gravel bed. This reflects the volume of the basin that is free space and is available for stormwater. ADS StormTech drawings are included in Appendix F that show the preliminary layout, sections, and details of the underground system; further specifications such as invert evaluations will be provided in the Final Hydrology and Hydraulics Study. 3.3 DRAWDOWN TIME DETERMINATION Drawdown time is the amount of time the design volume takes to pass through the effective storage area of the retention basin. The drawdown time must not exceed 48 hours in order to implement proper vector control and prevent other nuisance issues. The drawdown time for the proposed underground storage basin was analyzed using an infiltration rate acquired by two percolation tests. The percolation test measures the length of time required for a quantity of water to infiltrate into the soil, this is often called a “percolation rate”. The percolation rate is related to, but not equal to, the infiltration rate. The infiltration rate is a measure of the speed at which water progresses downward into the soil and the percolation rate measures the downwards and lateral progression through the soil. Based on the “Porchet Method”, the following equation was used to convert the percolation rates to the tested infiltration rate, I t: The percolation testing determined an infiltration rate of 5.51 in/hr and 5.38 in/hr. A design www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 factor of safety prescribed by the Stormwater Quality Best Management Handbook for Low Impact Development was used to determine a design infiltration rate. The factor of safety is used to account for the actual infiltration rate of the soil which is influenced by the heterogeneous nature of soil, post-grading compaction and accumulation of sedimentary particles at the infiltration surface. A factor of safety of 3 was applied to the acquired more conservative 5.38 in/hr infiltration rate. This resulted in a design infiltration rate of 1.79 in/hr. However, the Palm Desert maximum infiltration rate for design is 1 in/hr, therefore 1 in/hr was used to calculate the drawdown time of 39.34 hours, which falls within the 48-hour maximum. The drawdown calculation and percolation test sheets can be found in Appendix E. 3.4 RATIONAL METHOD HYDROLOGY RESULTS The peak 100-year discharges were calculated using the Rational Method via CivilDesign software, as prescribed by the Hydrology Manual. The calculated design flow rate of 4.02 cubic feet per second in DMA A1, 0.84 cubic feet per second in DMA A2, and 2.63 cubic feet per second in DMA A3 were used for the sizing of the inlet catch basins within each drainage areas. A 36”x36” grate will be used in A1 and A3 and a 24”x24” grate will be used in A2, ensuring an acceptable depth and gutter spread at each inlet. Since there will be a negligible change in runoff due the expansion on Parcel A, the preliminary size of the proposed catch basin inlet added to the existing drainage system is suggested to be 24”x24”; a detailed calculation of the grate inlet will be performed in the Final Report. Detailed rational method calculations and catch basin inlet size calculations can be found in Appendix G. Storm drain size calculations will be provided in the Final Report along with an in-depth discussion of Manning’s N values. SECTION 4 – CONCLUSION The methodologies used in this study are in compliance with the City of Palm Desert and RCFC&WCD Criteria. The project site lies within FEMA designated Zone X, Areas determined to be outside the 0.2% annual chance floodplain. The underground storage chambers will retain the volume of 100% of the 100-year 24-hour storm of the existing condition. Based on these design calculations, the proposed drainage system will capture sufficient onsite runoff to prevent significant flooding during the 100-year storm event. There are no anticipated negative upstream or downstream impacts. SECTION 5 – REFERENCES 1. Riverside County Flood Control and Water Conservation District Hydrology Manual, 1978. 2. Palm Desert Water Quality Ordinance (Municipal Code Section Chapter 24.20 and 26.49) 3. Whitewater River Region Stormwater Quality Best Management Practice Design Handbook for Low Impact Development, June 2014. 4. Hydrology Study for Monterey 170 LLC Parcel Map No. 24255 in The City of Palm Desert, November 2002. 5. Hydrology Report for Retention Basin for Palm Desert Assessment District 2004- 02 combined with Parcel Map No. 24255 (Monterey 170), December 2005. 6. Hydrology Report for Palm Desert Assessment District 2004-02, June 2006. www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX A FEMA FLOOD HAZARD LAYER FIRMETTE National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 6/23/2022 at 5:42 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 116°23'17"W 33°48'19"N 116°22'39"W 33°47'50"N Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX B CITY OF PALM DESERT REGIONAL RETENTION BASIN MAPS www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX C PRE-DEVELOPMENT CONDITION HYDROLOGY MAP POST-DEVELOPMENT CONDITION HYDROLOGY MAP 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211 760-346-7481 CI V I LS T ATE OF CA L IF O RNIAREGISTERED P R O F ESSIONAL E N GI NEERTODD L . PIT NE R No. C58606 "NOT FOR CONSTRUCTION"REVISED: 08/11/2022 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERTOD D L. PITNERNo. C58606"NOT FOR CONSTRUCTION"REVISED: 08/11/2022 www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX D WEB SOIL SURVEY – HYDROLOGIC SOIL GROUP NOAA PRECIPITATION DATA RCFC&WCD PLATE E-6.1 & E-6.2 Hydrologic Soil Group—Riverside County, Coachella Valley Area, California (CarMax Building/Parking Lot Expansion and Carwash Addition) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 1 of 437401103740150374019037402303740270374031037403503740110374015037401903740230374027037403103740350556970557010557050557090557130557170557210557250557290557330557370 556970 557010 557050 557090 557130 557170 557210 557250 557290 557330 557370 33° 48' 7'' N 116° 23' 4'' W33° 48' 7'' N116° 22' 48'' W33° 47' 58'' N 116° 23' 4'' W33° 47' 58'' N 116° 22' 48'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300 Feet 0 25 50 100 150 Meters Map Scale: 1:1,960 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Riverside County, Coachella Valley Area, California Survey Area Data: Version 13, Sep 15, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Feb 3, 2021—May 27, 2021 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group—Riverside County, Coachella Valley Area, California (CarMax Building/Parking Lot Expansion and Carwash Addition) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 2 of 4 Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CpA Coachella fine sand, 0 to 2 percent slopes A 6.2 100.0% Totals for Area of Interest 6.2 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Hydrologic Soil Group—Riverside County, Coachella Valley Area, California CarMax Building/Parking Lot Expansion and Carwash Addition Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 3 of 4 Tie-break Rule: Higher Hydrologic Soil Group—Riverside County, Coachella Valley Area, California CarMax Building/Parking Lot Expansion and Carwash Addition Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2022 Page 4 of 4 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 1/4 NOAA Atlas 14, Volume 6, Version 2 Location name: Palm Desert, California, USA* Latitude: 33.8012°, Longitude: -116.3828° Elevation: 200.66 ft** * source: ESRI Maps ** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sarah Dietz, Sarah Heim, Lillian Hiner, Kazungu Maitaria, Deborah Martin, Sandra Pavlovic, Ishani Roy, Carl Trypaluk, Dale Unruh, Fenglin Yan, Michael Yekta, Tan Zhao, Geoffrey Bonnin, Daniel Brewer, Li-Chuan Chen, Tye Parzybok, John Yarchoan NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 0.055 (0.046‑0.067) 0.084 (0.070‑0.102) 0.128 (0.106‑0.156) 0.169 (0.139‑0.207) 0.233 (0.185‑0.295) 0.289 (0.225‑0.375) 0.354 (0.269‑0.471) 0.430 (0.317‑0.588) 0.549 (0.389‑0.784) 0.659 (0.450‑0.974) 10-min 0.079 (0.066‑0.096) 0.121 (0.100‑0.146) 0.184 (0.152‑0.223) 0.242 (0.199‑0.297) 0.333 (0.265‑0.423) 0.414 (0.323‑0.538) 0.508 (0.386‑0.675) 0.616 (0.455‑0.843) 0.787 (0.557‑1.12) 0.944 (0.645‑1.40) 15-min 0.096 (0.080‑0.116) 0.146 (0.121‑0.177) 0.222 (0.184‑0.270) 0.292 (0.241‑0.359) 0.403 (0.321‑0.512) 0.501 (0.390‑0.650) 0.614 (0.466‑0.817) 0.745 (0.550‑1.02) 0.952 (0.674‑1.36) 1.14 (0.780‑1.69) 30-min 0.148 (0.123‑0.180) 0.226 (0.188‑0.274) 0.344 (0.285‑0.419) 0.453 (0.373‑0.556) 0.625 (0.497‑0.793) 0.777 (0.605‑1.01) 0.951 (0.722‑1.26) 1.16 (0.852‑1.58) 1.48 (1.04‑2.11) 1.77 (1.21‑2.62) 60-min 0.222 (0.185‑0.269) 0.338 (0.282‑0.411) 0.515 (0.427‑0.627) 0.678 (0.558‑0.832) 0.935 (0.744‑1.19) 1.16 (0.905‑1.51) 1.42 (1.08‑1.89) 1.73 (1.28‑2.37) 2.21 (1.56‑3.15) 2.65 (1.81‑3.92) 2-hr 0.324 (0.270‑0.393) 0.481 (0.401‑0.584) 0.715 (0.593‑0.870) 0.927 (0.763‑1.14) 1.25 (0.997‑1.59) 1.54 (1.20‑1.99) 1.86 (1.41‑2.47) 2.22 (1.64‑3.04) 2.78 (1.96‑3.96) 3.27 (2.23‑4.83) 3-hr 0.393 (0.327‑0.476) 0.579 (0.482‑0.702) 0.852 (0.707‑1.04) 1.10 (0.905‑1.35) 1.48 (1.18‑1.88) 1.80 (1.41‑2.34) 2.17 (1.65‑2.88) 2.58 (1.91‑3.53) 3.21 (2.27‑4.58) 3.75 (2.56‑5.55) 6-hr 0.540 (0.450‑0.654) 0.795 (0.662‑0.965) 1.17 (0.970‑1.42) 1.50 (1.24‑1.85) 2.01 (1.60‑2.56) 2.45 (1.91‑3.18) 2.93 (2.23‑3.90) 3.48 (2.57‑4.76) 4.30 (3.04‑6.13) 5.00 (3.42‑7.40) 12-hr 0.638 (0.532‑0.773) 0.960 (0.799‑1.17) 1.43 (1.19‑1.75) 1.86 (1.53‑2.29) 2.51 (2.00‑3.19) 3.07 (2.39‑3.99) 3.70 (2.81‑4.92) 4.41 (3.26‑6.04) 5.49 (3.88‑7.83) 6.42 (4.38‑9.49) 24-hr 0.739 (0.655‑0.852) 1.14 (1.01‑1.32) 1.74 (1.54‑2.02) 2.28 (2.00‑2.66) 3.11 (2.63‑3.74) 3.82 (3.17‑4.70) 4.62 (3.75‑5.82) 5.53 (4.37‑7.15) 6.92 (5.25‑9.32) 8.13 (5.96‑11.3) 2-day 0.805 (0.712‑0.928) 1.27 (1.12‑1.47) 1.95 (1.72‑2.26) 2.56 (2.24‑2.98) 3.47 (2.94‑4.18) 4.25 (3.53‑5.23) 5.12 (4.15‑6.44) 6.10 (4.81‑7.88) 7.57 (5.74‑10.2) 8.83 (6.48‑12.3) 3-day 0.836 (0.740‑0.964) 1.33 (1.18‑1.54) 2.05 (1.81‑2.37) 2.69 (2.35‑3.14) 3.65 (3.09‑4.39) 4.46 (3.70‑5.48) 5.35 (4.34‑6.74) 6.36 (5.02‑8.22) 7.85 (5.96‑10.6) 9.13 (6.70‑12.7) 4-day 0.860 (0.761‑0.992) 1.38 (1.22‑1.59) 2.13 (1.88‑2.46) 2.79 (2.44‑3.26) 3.78 (3.20‑4.55) 4.62 (3.83‑5.67) 5.54 (4.49‑6.97) 6.57 (5.18‑8.49) 8.09 (6.14‑10.9) 9.40 (6.89‑13.1) 7-day 0.909 (0.805‑1.05) 1.47 (1.30‑1.70) 2.29 (2.02‑2.65) 3.01 (2.63‑3.51) 4.08 (3.46‑4.92) 4.98 (4.14‑6.12) 5.97 (4.84‑7.51) 7.06 (5.57‑9.13) 8.68 (6.58‑11.7) 10.0 (7.37‑14.0) 10-day 0.950 (0.841‑1.10) 1.55 (1.37‑1.79) 2.42 (2.13‑2.80) 3.18 (2.78‑3.71) 4.32 (3.66‑5.20) 5.27 (4.38‑6.48) 6.31 (5.12‑7.94) 7.47 (5.89‑9.65) 9.17 (6.96‑12.3) 10.6 (7.78‑14.8) 20-day 1.02 (0.904‑1.18) 1.68 (1.49‑1.94) 2.64 (2.33‑3.05) 3.49 (3.05‑4.07) 4.75 (4.03‑5.72) 5.82 (4.83‑7.15) 6.98 (5.66‑8.78) 8.26 (6.52‑10.7) 10.1 (7.70‑13.7) 11.7 (8.60‑16.3) 30-day 1.13 (1.00‑1.30) 1.86 (1.65‑2.15) 2.93 (2.59‑3.39) 3.89 (3.40‑4.53) 5.32 (4.51‑6.41) 6.52 (5.42‑8.02) 7.84 (6.36‑9.86) 9.29 (7.33‑12.0) 11.4 (8.66‑15.4) 13.2 (9.68‑18.4) 45-day 1.22 (1.08‑1.41) 2.02 (1.78‑2.33) 3.19 (2.81‑3.69) 4.24 (3.71‑4.95) 5.84 (4.95‑7.03) 7.19 (5.97‑8.83) 8.66 (7.03‑10.9) 10.3 (8.12‑13.3) 12.7 (9.61‑17.1) 14.7 (10.8‑20.4) 60-day 1.32 (1.17‑1.53) 2.18 (1.93‑2.52) 3.46 (3.05‑4.00) 4.62 (4.04‑5.38) 6.37 (5.39‑7.67) 7.86 (6.53‑9.66) 9.50 (7.70‑11.9) 11.3 (8.92‑14.6) 13.9 (10.6‑18.8) 16.2 (11.9‑22.5) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 2/4 Back to Top Maps & aerials Small scale terrain 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 3/4 Large scale terrain Large scale map Large scale aerial + – 3km 2mi + – 100km 60mi + – 100km 60mi 6/23/22, 2:28 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.8012&lon=-116.3828&data=depth&units=english&series=pds 4/4 Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer + – 100km 60mi www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX E SYNTHETIC UNIT HYDROGRAPH CALCULATIONS DRAWDOWN CALCULATIONS PERCOLATION TEST SHEETS 1 & 2 1 of 6 HYDROLOGY CALCULATIONS - Using the RCFC&WCD Short Cut Unit Hydrograph Method Area Designations Existing Conditions Basin A Drainage Area (ac.)1.5700 Unit time (minutes)5 5 5 15 100 Year Storm Duration (hrs)1 3 6 24 Total Precipitation (Plates D-4.4,E-5.2, 5.4, 5.6)(in.)1.42 2.17 2.93 4.62 Or data from NOAA interactive website Soils Group A AMC index II Runoff Number (plate E-6.1)78 Plate E-6.2 Pervious Area Loss Rate (Fp)(in/hr)0.27 (AMC II) Percentage of Impervious Cover (Ai)(%) (plate E-6.3)0 Weighted Average Loss Rate (F=Fp(1-.9Ai))(in./hr.)0.27 (used for 1, 3, and 6 hour storm, the 24 hour storm uses variable maximum loss rate per plate E-1.1 (3 of 6)) Low Loss Rate Percent (%) 80 Retention Basin Percolation Rate (in/hr)1 (also used for drywell percolation rate) Percolation is taken incrementally. Basin volume is calculated using the "truncated pyramid" formula, a more conservative estimate than "averaged end areas" sometimes used (Drywell can be "zeroed out" by reducing numbers to less than .001, but should not entered as zeros or program chokes.) Drywell storage includes 40% of the 1' wide rock bed surrounding the drywell: formula (upper)*PI()*(diam/2)^2+(lower)*PI()*((diam/2)^2+0.4*((diam/2+(grav+0.4166))^2-(diam/2+0.4166)^2)) The drywell wall thickness is assumed at 5" (0.4166) and the gravel bed width is variable "grav" Drywell is zeroed out by entering .001 for values Drywell design factors Upper sec. (ft.)=0.001 Lower sec. (ft.)=0.001 Ring diam. (ft.) =0.001 Drywell lower max. (cf)=0.00 Upper max.(cf)=0.00 Gravel bed width around drwyell=1 Drywell total(cf)=0.00 Ret. Basin design (area, depth) Top =1969.45 s.f.Bot. =1969.45 s.f.Max. Depth (d)=3.275 Max. storage=6449.95 (d/3)*(bottom+top+(bottom*top)^0.50) Formulas vol=(h/3)*(bottom+top+(bottom*top)^0.50) area=bottom+(h/d)*(top-bottom)h=(vol*3)/(bottom+top+(bottom*top)^0.5)(values must be non-zero or error occurs) Outside input from:N/A 1 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 3.7 0.6305 0.2700 N/A 0.3605 0.5707 171.20 0.00 0.00 0.00 0.00 0.00 171.20 1969.45 13.68 157.52 0.08 0.00 0.00 0:10 4.8 0.8179 0.2700 N/A 0.5479 0.8674 260.22 0.00 0.00 0.00 0.00 0.00 260.22 1969.45 13.68 404.07 0.21 0.00 0.00 0:15 5.1 0.8690 0.2700 N/A 0.5990 0.9483 284.50 0.00 0.00 0.00 0.00 0.00 284.50 1969.45 13.68 674.89 0.34 0.00 0.00 0:20 4.9 0.8350 0.2700 N/A 0.5650 0.8944 268.31 0.00 0.00 0.00 0.00 0.00 268.31 1969.45 13.68 929.53 0.47 0.00 0.00 0:25 6.6 1.1246 0.2700 N/A 0.8546 1.3530 405.89 0.00 0.00 0.00 0.00 0.00 405.89 1969.45 13.68 1321.74 0.67 0.00 0.00 0:30 7.3 1.2439 0.2700 N/A 0.9739 1.5418 462.54 0.00 0.00 0.00 0.00 0.00 462.54 1969.45 13.68 1770.60 0.90 0.00 0.00 0:35 8.4 1.4314 0.2700 N/A 1.1614 1.8385 551.56 0.00 0.00 0.00 0.00 0.00 551.56 1969.45 13.68 2308.48 1.17 0.00 0.00 0:40 9 1.5336 0.2700 N/A 1.2636 2.0004 600.12 0.00 0.00 0.00 0.00 0.00 600.12 1969.45 13.68 2894.92 1.47 0.00 0.00 0:45 12.3 2.0959 0.2700 N/A 1.8259 2.8906 867.18 0.00 0.00 0.00 0.00 0.00 867.18 1969.45 13.68 3748.42 1.90 0.00 0.00 0:50 17.6 2.9990 0.2700 N/A 2.7290 4.3203 1296.09 0.00 0.00 0.00 0.00 0.00 1296.09 1969.45 13.68 5030.83 2.55 0.00 0.00 0:55 16.1 2.7434 0.2700 N/A 2.4734 3.9157 1174.70 0.00 0.00 0.00 0.00 0.00 1174.70 1969.45 13.68 6191.85 3.14 0.00 0.00 1:00 4.2 0.7157 0.2700 N/A 0.4457 0.7055 211.66 0.00 0.00 0.00 0.00 0.00 211.66 1969.45 13.68 6389.84 3.24 0.00 0.00 PEAK 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6376.17 3.24 0.00 0.00 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6362.49 3.23 0.00 0.00 1:15 0 0.0000 0.2700 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6348.81 3.22 0.00 0.00 Total volume (cf)6553.97 Total Overflow (cf)0.00 2 of 6 3 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 1.3 0.34 0.27 N/A 0.0685 0.1085 32.54 0.00 0.00 0.00 0.00 0.00 32.54 1969.45 13.68 18.86 0.01 0.00 0.00 0:10 1.3 0.34 0.27 N/A 0.0685 0.1085 32.54 0.00 0.00 0.00 0.00 0.00 32.54 1969.45 13.68 37.73 0.02 0.00 0.00 0:15 1.1 0.29 0.27 0.23 0.0573 0.0907 27.21 0.00 0.00 0.00 0.00 0.00 27.21 1969.45 13.68 51.26 0.03 0.00 0.00 0:20 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 94.86 0.05 0.00 0.00 0:25 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 138.46 0.07 0.00 0.00 0:30 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 219.16 0.11 0.00 0.00 0:35 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 262.76 0.13 0.00 0.00 0:40 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 343.46 0.17 0.00 0.00 0:45 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 424.16 0.22 0.00 0.00 0:50 1.5 0.39 0.27 N/A 0.1206 0.1909 57.28 0.00 0.00 0.00 0.00 0.00 57.28 1969.45 13.68 467.76 0.24 0.00 0.00 0:55 1.6 0.42 0.27 N/A 0.1466 0.2321 69.64 0.00 0.00 0.00 0.00 0.00 69.64 1969.45 13.68 523.72 0.27 0.00 0.00 1:00 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 604.42 0.31 0.00 0.00 1:05 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 734.59 0.37 0.00 0.00 1:10 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 864.76 0.44 0.00 0.00 1:15 2.2 0.57 0.27 N/A 0.3029 0.4795 143.85 0.00 0.00 0.00 0.00 0.00 143.85 1969.45 13.68 994.93 0.51 0.00 0.00 1:20 2 0.52 0.27 N/A 0.2508 0.3970 119.11 0.00 0.00 0.00 0.00 0.00 119.11 1969.45 13.68 1100.36 0.56 0.00 0.00 1:25 2.6 0.68 0.27 N/A 0.4070 0.6444 193.31 0.00 0.00 0.00 0.00 0.00 193.31 1969.45 13.68 1280.00 0.65 0.00 0.00 1:30 2.7 0.70 0.27 N/A 0.4331 0.6856 205.68 0.00 0.00 0.00 0.00 0.00 205.68 1969.45 13.68 1472.00 0.75 0.00 0.00 1:35 2.4 0.62 0.27 N/A 0.3550 0.5619 168.58 0.00 0.00 0.00 0.00 0.00 168.58 1969.45 13.68 1626.91 0.83 0.00 0.00 1:40 2.7 0.70 0.27 N/A 0.4331 0.6856 205.68 0.00 0.00 0.00 0.00 0.00 205.68 1969.45 13.68 1818.91 0.92 0.00 0.00 1:45 3.3 0.86 0.27 N/A 0.5893 0.9329 279.88 0.00 0.00 0.00 0.00 0.00 279.88 1969.45 13.68 2085.12 1.06 0.00 0.00 1:50 3.1 0.81 0.27 N/A 0.5372 0.8505 255.15 0.00 0.00 0.00 0.00 0.00 255.15 1969.45 13.68 2326.59 1.18 0.00 0.00 1:55 2.9 0.76 0.27 N/A 0.4852 0.7680 230.41 0.00 0.00 0.00 0.00 0.00 230.41 1969.45 13.68 2543.33 1.29 0.00 0.00 2:00 3 0.78 0.27 N/A 0.5112 0.8093 242.78 0.00 0.00 0.00 0.00 0.00 242.78 1969.45 13.68 2772.43 1.41 0.00 0.00 2:05 3.1 0.81 0.27 N/A 0.5372 0.8505 255.15 0.00 0.00 0.00 0.00 0.00 255.15 1969.45 13.68 3013.90 1.53 0.00 0.00 2:10 4.2 1.09 0.27 N/A 0.8237 1.3040 391.19 0.00 0.00 0.00 0.00 0.00 391.19 1969.45 13.68 3391.41 1.72 0.00 0.00 2:15 5 1.30 0.27 N/A 1.0320 1.6337 490.12 0.00 0.00 0.00 0.00 0.00 490.12 1969.45 13.68 3867.86 1.96 0.00 0.00 2:20 3.5 0.91 0.27 N/A 0.6414 1.0154 304.62 0.00 0.00 0.00 0.00 0.00 304.62 1969.45 13.68 4158.80 2.11 0.00 0.00 2:25 6.8 1.77 0.27 N/A 1.5007 2.3758 712.73 0.00 0.00 0.00 0.00 0.00 712.73 1969.45 13.68 4857.85 2.47 0.00 0.00 2:30 7.3 1.90 0.27 N/A 1.6309 2.5819 774.56 0.00 0.00 0.00 0.00 0.00 774.56 1969.45 13.68 5618.74 2.85 0.00 0.00 2:35 8.2 2.14 0.27 N/A 1.8653 2.9529 885.87 0.00 0.00 0.00 0.00 0.00 885.87 1969.45 13.68 6449.95 3.28 40.98 0.14 2:40 5.9 1.54 0.27 N/A 1.2664 2.0048 601.43 0.00 0.00 0.00 0.00 0.00 601.43 1969.45 13.68 6449.95 3.28 587.75 1.96 PEAK 2:45 2 0.52 0.27 N/A 0.2508 0.3970 119.11 0.00 0.00 0.00 0.00 0.00 119.11 1969.45 13.68 6449.95 3.28 105.43 0.35 2:50 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 6449.95 3.28 80.70 0.27 2:55 1.8 0.47 0.27 N/A 0.1987 0.3146 94.38 0.00 0.00 0.00 0.00 0.00 94.38 1969.45 13.68 6449.95 3.28 80.70 0.27 3:00 0.6 0.16 0.27 0.12 0.0312 0.0495 14.84 0.00 0.00 0.00 0.00 0.00 14.84 1969.45 13.68 6449.95 3.28 1.16 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6436.27 3.27 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6422.60 3.26 0.00 0.00 3:15 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6408.92 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6395.24 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6381.57 3.24 0.00 0.00 3:30 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6367.89 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6354.21 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6340.53 3.22 0.00 0.00 Total volume (cf)7839.04 Total Overflow (cf)896.73 STORM WATER CHANNEL 3 of 6 6 Hour Storm in 5 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:05 0.5 0.18 0.27 0.14 0.0352 0.0557 16.70 0.00 0.00 0.00 0.00 0.00 16.70 1969.45 13.68 3.02 0.00 0.00 0.00 0:10 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 9.38 0.00 0.00 0.00 0:15 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 15.74 0.01 0.00 0.00 0:20 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 22.10 0.01 0.00 0.00 0:25 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 28.46 0.01 0.00 0.00 0:30 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 38.17 0.02 0.00 0.00 0:35 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 47.87 0.02 0.00 0.00 0:40 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 57.57 0.03 0.00 0.00 0:45 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 67.27 0.03 0.00 0.00 0:50 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 76.97 0.04 0.00 0.00 0:55 0.7 0.25 0.27 0.20 0.0492 0.0779 23.38 0.00 0.00 0.00 0.00 0.00 23.38 1969.45 13.68 86.67 0.04 0.00 0.00 1:00 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 99.71 0.05 0.00 0.00 1:05 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 112.75 0.06 0.00 0.00 1:10 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 125.79 0.06 0.00 0.00 1:15 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 138.83 0.07 0.00 0.00 1:20 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 151.87 0.08 0.00 0.00 1:25 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 164.91 0.08 0.00 0.00 1:30 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 177.95 0.09 0.00 0.00 1:35 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 191.00 0.10 0.00 0.00 1:40 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 204.04 0.10 0.00 0.00 1:45 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 217.08 0.11 0.00 0.00 1:50 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 230.12 0.12 0.00 0.00 1:55 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 243.16 0.12 0.00 0.00 2:00 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 259.54 0.13 0.00 0.00 2:05 0.8 0.28 0.27 0.23 0.0563 0.0891 26.72 0.00 0.00 0.00 0.00 0.00 26.72 1969.45 13.68 272.58 0.14 0.00 0.00 2:10 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 288.96 0.15 0.00 0.00 2:15 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 305.34 0.16 0.00 0.00 2:20 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 321.72 0.16 0.00 0.00 2:25 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 338.10 0.17 0.00 0.00 2:30 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 354.48 0.18 0.00 0.00 2:35 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 370.86 0.19 0.00 0.00 2:40 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 387.24 0.20 0.00 0.00 2:45 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 412.32 0.21 0.00 0.00 2:50 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 437.40 0.22 0.00 0.00 2:55 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 462.47 0.23 0.00 0.00 3:00 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 487.55 0.25 0.00 0.00 3:05 1 0.35 0.27 N/A 0.0816 0.1292 38.75 0.00 0.00 0.00 0.00 0.00 38.75 1969.45 13.68 512.63 0.26 0.00 0.00 3:10 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 554.40 0.28 0.00 0.00 3:15 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 596.18 0.30 0.00 0.00 3:20 1.1 0.39 0.27 N/A 0.1168 0.1848 55.45 0.00 0.00 0.00 0.00 0.00 55.45 1969.45 13.68 637.95 0.32 0.00 0.00 3:25 1.2 0.42 0.27 N/A 0.1519 0.2405 72.15 0.00 0.00 0.00 0.00 0.00 72.15 1969.45 13.68 696.43 0.35 0.00 0.00 3:30 1.3 0.46 0.27 N/A 0.1871 0.2962 88.85 0.00 0.00 0.00 0.00 0.00 88.85 1969.45 13.68 771.60 0.39 0.00 0.00 3:35 1.4 0.49 0.27 N/A 0.2222 0.3518 105.55 0.00 0.00 0.00 0.00 0.00 105.55 1969.45 13.68 863.47 0.44 0.00 0.00 3:40 1.4 0.49 0.27 N/A 0.2222 0.3518 105.55 0.00 0.00 0.00 0.00 0.00 105.55 1969.45 13.68 955.34 0.49 0.00 0.00 3:45 1.5 0.53 0.27 N/A 0.2574 0.4075 122.25 0.00 0.00 0.00 0.00 0.00 122.25 1969.45 13.68 1063.91 0.54 0.00 0.00 3:50 1.5 0.53 0.27 N/A 0.2574 0.4075 122.25 0.00 0.00 0.00 0.00 0.00 122.25 1969.45 13.68 1172.48 0.60 0.00 0.00 3:55 1.6 0.56 0.27 N/A 0.2926 0.4631 138.94 0.00 0.00 0.00 0.00 0.00 138.94 1969.45 13.68 1297.75 0.66 0.00 0.00 4:00 1.6 0.56 0.27 N/A 0.2926 0.4631 138.94 0.00 0.00 0.00 0.00 0.00 138.94 1969.45 13.68 1423.01 0.72 0.00 0.00 4:05 1.7 0.60 0.27 N/A 0.3277 0.5188 155.64 0.00 0.00 0.00 0.00 0.00 155.64 1969.45 13.68 1564.98 0.79 0.00 0.00 4:10 1.8 0.63 0.27 N/A 0.3629 0.5745 172.34 0.00 0.00 0.00 0.00 0.00 172.34 1969.45 13.68 1723.64 0.88 0.00 0.00 4 of 6 4:15 1.9 0.67 0.27 N/A 0.3980 0.6301 189.04 0.00 0.00 0.00 0.00 0.00 189.04 1969.45 13.68 1899.01 0.96 0.00 0.00 4:20 2 0.70 0.27 N/A 0.4332 0.6858 205.74 0.00 0.00 0.00 0.00 0.00 205.74 1969.45 13.68 2091.07 1.06 0.00 0.00 4:25 2.1 0.74 0.27 N/A 0.4684 0.7415 222.44 0.00 0.00 0.00 0.00 0.00 222.44 1969.45 13.68 2299.83 1.17 0.00 0.00 4:30 2.1 0.74 0.27 N/A 0.4684 0.7415 222.44 0.00 0.00 0.00 0.00 0.00 222.44 1969.45 13.68 2508.58 1.27 0.00 0.00 4:35 2.2 0.77 0.27 N/A 0.5035 0.7971 239.13 0.00 0.00 0.00 0.00 0.00 239.13 1969.45 13.68 2734.04 1.39 0.00 0.00 4:40 2.3 0.81 0.27 N/A 0.5387 0.8528 255.83 0.00 0.00 0.00 0.00 0.00 255.83 1969.45 13.68 2976.20 1.51 0.00 0.00 4:45 2.4 0.84 0.27 N/A 0.5738 0.9084 272.53 0.00 0.00 0.00 0.00 0.00 272.53 1969.45 13.68 3235.05 1.64 0.00 0.00 4:50 2.4 0.84 0.27 N/A 0.5738 0.9084 272.53 0.00 0.00 0.00 0.00 0.00 272.53 1969.45 13.68 3493.91 1.77 0.00 0.00 4:55 2.5 0.88 0.27 N/A 0.6090 0.9641 289.23 0.00 0.00 0.00 0.00 0.00 289.23 1969.45 13.68 3769.46 1.91 0.00 0.00 5:00 2.6 0.91 0.27 N/A 0.6442 1.0198 305.93 0.00 0.00 0.00 0.00 0.00 305.93 1969.45 13.68 4061.71 2.06 0.00 0.00 5:05 3.1 1.09 0.27 N/A 0.8200 1.2981 389.42 0.00 0.00 0.00 0.00 0.00 389.42 1969.45 13.68 4437.45 2.25 0.00 0.00 5:10 3.6 1.27 0.27 N/A 0.9958 1.5764 472.91 0.00 0.00 0.00 0.00 0.00 472.91 1969.45 13.68 4896.69 2.49 0.00 0.00 5:15 3.9 1.37 0.27 N/A 1.1012 1.7434 523.01 0.00 0.00 0.00 0.00 0.00 523.01 1969.45 13.68 5406.02 2.74 0.00 0.00 5:20 4.2 1.48 0.27 N/A 1.2067 1.9103 573.10 0.00 0.00 0.00 0.00 0.00 573.10 1969.45 13.68 5965.44 3.03 0.00 0.00 5:25 4.7 1.65 0.27 N/A 1.3825 2.1886 656.59 0.00 0.00 0.00 0.00 0.00 656.59 1969.45 13.68 6449.95 3.28 158.41 0.53 5:30 5.6 1.97 0.27 N/A 1.6990 2.6896 806.88 0.00 0.00 0.00 0.00 0.00 806.88 1969.45 13.68 6449.95 3.28 793.20 2.64 PEAK 5:35 1.9 0.67 0.27 N/A 0.3980 0.6301 189.04 0.00 0.00 0.00 0.00 0.00 189.04 1969.45 13.68 6449.95 3.28 175.36 0.58 5:40 0.9 0.32 0.27 0.25 0.0633 0.1002 30.06 0.00 0.00 0.00 0.00 0.00 30.06 1969.45 13.68 6449.95 3.28 16.38 0.05 5:45 0.6 0.21 0.27 0.17 0.0422 0.0668 20.04 0.00 0.00 0.00 0.00 0.00 20.04 1969.45 13.68 6449.95 3.28 6.36 0.02 5:50 0.5 0.18 0.27 0.14 0.0352 0.0557 16.70 0.00 0.00 0.00 0.00 0.00 16.70 1969.45 13.68 6449.95 3.28 3.02 0.01 5:55 0.3 0.11 0.27 0.08 0.0211 0.0334 10.02 0.00 0.00 0.00 0.00 0.00 10.02 1969.45 13.68 6446.29 3.27 0.00 0.00 6:00 0.2 0.07 0.27 0.06 0.0141 0.0223 6.68 0.00 0.00 0.00 0.00 0.00 6.68 1969.45 13.68 6439.29 3.27 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6425.62 3.26 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6411.94 3.26 0.00 0.00 6:15 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6398.26 3.25 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6384.59 3.24 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6370.91 3.23 0.00 0.00 6:30 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6357.23 3.23 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6343.56 3.22 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6329.88 3.21 0.00 0.00 6:45 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6316.20 3.21 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6302.53 3.20 0.00 0.00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6288.85 3.19 0.00 0.00 7:00 0 0.00 0.27 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 13.68 6275.17 3.19 0.00 0.00 Total volume (cf)8576.76 Total Overflow (cf)1152.74 STORM WATER CHANNEL 5 of 6 24 Hour Storm in 15 minute increments Drywell Drywell Drywell Drywell Overflow Basin Basin Basin Time Pattern Storm Loss Rate Value Effective Flow Flow Outside Retention Period Storage Storage To Retention Period Storage Storage Overflow Overflow %Rain (in/hr)Max.Min.Rain (in/hr)Rate (cfs)Vol. (cf)Input (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Basin (cf)Area (sf)Perc. (cf)Vol. (cf)Depth (ft)Vol. (cf)Rate (cfs) 0:15 0.2 0.04 0.47 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 10.53 0.00 0.00 0.00 0.00 0:30 0.3 0.06 0.47 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 0:45 0.3 0.06 0.46 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:00 0.4 0.07 0.46 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 1:15 0.3 0.06 0.45 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:30 0.3 0.06 0.45 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 1:45 0.3 0.06 0.44 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 15.80 0.00 0.00 0.00 0.00 2:00 0.4 0.07 0.44 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:15 0.4 0.07 0.43 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:30 0.4 0.07 0.43 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 21.06 0.00 0.00 0.00 0.00 2:45 0.5 0.09 0.42 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:00 0.5 0.09 0.42 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:15 0.5 0.09 0.41 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:30 0.5 0.09 0.40 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 3:45 0.5 0.09 0.40 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 26.33 0.00 0.00 0.00 0.00 4:00 0.6 0.11 0.39 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 31.60 0.00 0.00 0.00 0.00 4:15 0.6 0.11 0.39 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 31.60 0.00 0.00 0.00 0.00 4:30 0.7 0.13 0.38 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 4:45 0.7 0.13 0.38 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 5:00 0.8 0.15 0.37 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 1.10 0.00 0.00 0.00 5:15 0.6 0.11 0.37 0.09 0.0222 0.0351 31.60 0.00 0.00 0.00 0.00 0.00 31.60 1969.45 41.03 0.00 0.00 0.00 0.00 5:30 0.7 0.13 0.37 0.10 0.0259 0.0410 36.86 0.00 0.00 0.00 0.00 0.00 36.86 1969.45 36.86 0.00 0.00 0.00 0.00 5:45 0.8 0.15 0.36 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 1.10 0.00 0.00 0.00 6:00 0.8 0.15 0.36 0.12 0.0296 0.0468 42.13 0.00 0.00 0.00 0.00 0.00 42.13 1969.45 41.03 2.20 0.00 0.00 0.00 6:15 0.9 0.17 0.35 0.13 0.0333 0.0527 47.39 0.00 0.00 0.00 0.00 0.00 47.39 1969.45 41.03 8.56 0.00 0.00 0.00 6:30 0.9 0.17 0.35 0.13 0.0333 0.0527 47.39 0.00 0.00 0.00 0.00 0.00 47.39 1969.45 41.03 14.92 0.01 0.00 0.00 6:45 1 0.18 0.34 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 26.55 0.01 0.00 0.00 7:00 1 0.18 0.34 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 38.18 0.02 0.00 0.00 7:15 1 0.18 0.33 0.15 0.0370 0.0585 52.66 0.00 0.00 0.00 0.00 0.00 52.66 1969.45 41.03 49.81 0.03 0.00 0.00 7:30 1.1 0.20 0.33 0.16 0.0407 0.0644 57.93 0.00 0.00 0.00 0.00 0.00 57.93 1969.45 41.03 66.71 0.03 0.00 0.00 7:45 1.2 0.22 0.32 0.18 0.0444 0.0702 63.19 0.00 0.00 0.00 0.00 0.00 63.19 1969.45 41.03 88.87 0.05 0.00 0.00 8:00 1.3 0.24 0.32 0.19 0.0480 0.0761 68.46 0.00 0.00 0.00 0.00 0.00 68.46 1969.45 41.03 116.29 0.06 0.00 0.00 8:15 1.5 0.28 0.31 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 154.25 0.08 0.00 0.00 8:30 1.5 0.28 0.31 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 192.21 0.10 0.00 0.00 8:45 1.6 0.30 0.31 0.24 0.0591 0.0936 84.26 0.00 0.00 0.00 0.00 0.00 84.26 1969.45 41.03 235.44 0.12 0.00 0.00 9:00 1.7 0.31 0.30 0.25 0.0628 0.0995 89.52 0.00 0.00 0.00 0.00 0.00 89.52 1969.45 41.03 283.93 0.14 0.00 0.00 9:15 1.9 0.35 0.30 0.28 0.0702 0.1112 100.05 0.00 0.00 0.00 0.00 0.00 100.05 1969.45 41.03 342.95 0.17 0.00 0.00 9:30 2 0.37 0.29 N/A 0.0768 0.1216 109.45 0.00 0.00 0.00 0.00 0.00 109.45 1969.45 41.03 411.37 0.21 0.00 0.00 9:45 2.1 0.39 0.29 N/A 0.0995 0.1575 141.76 0.00 0.00 0.00 0.00 0.00 141.76 1969.45 41.03 512.10 0.26 0.00 0.00 10:00 2.2 0.41 0.28 N/A 0.1221 0.1933 174.01 0.00 0.00 0.00 0.00 0.00 174.01 1969.45 41.03 645.07 0.33 0.00 0.00 10:15 1.5 0.28 0.28 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 683.03 0.35 0.00 0.00 10:30 1.5 0.28 0.28 0.22 0.0554 0.0878 78.99 0.00 0.00 0.00 0.00 0.00 78.99 1969.45 41.03 720.99 0.37 0.00 0.00 10:45 2 0.37 0.27 N/A 0.0974 0.1542 138.76 0.00 0.00 0.00 0.00 0.00 138.76 1969.45 41.03 818.72 0.42 0.00 0.00 11:00 2 0.37 0.27 N/A 0.1014 0.1605 144.45 0.00 0.00 0.00 0.00 0.00 144.45 1969.45 41.03 922.15 0.47 0.00 0.00 11:15 1.9 0.35 0.26 N/A 0.0869 0.1375 123.75 0.00 0.00 0.00 0.00 0.00 123.75 1969.45 41.03 1004.86 0.51 0.00 0.00 11:30 1.9 0.35 0.26 N/A 0.0908 0.1437 129.32 0.00 0.00 0.00 0.00 0.00 129.32 1969.45 41.03 1093.15 0.56 0.00 0.00 11:45 1.7 0.31 0.26 0.25 0.0628 0.0995 89.52 0.00 0.00 0.00 0.00 0.00 89.52 1969.45 41.03 1141.64 0.58 0.00 0.00 12:00 1.8 0.33 0.25 N/A 0.0800 0.1266 113.94 0.00 0.00 0.00 0.00 0.00 113.94 1969.45 41.03 1214.55 0.62 0.00 0.00 12:15 2.5 0.46 0.25 N/A 0.2131 0.3374 303.63 0.00 0.00 0.00 0.00 0.00 303.63 1969.45 41.03 1477.15 0.75 0.00 0.00 12:30 2.6 0.48 0.25 N/A 0.2353 0.3725 335.28 0.00 0.00 0.00 0.00 0.00 335.28 1969.45 41.03 1771.40 0.90 0.00 0.00 6 of 6 12:45 2.8 0.52 0.24 N/A 0.2760 0.4369 393.20 0.00 0.00 0.00 0.00 0.00 393.20 1969.45 41.03 2123.56 1.08 0.00 0.00 13:00 2.9 0.54 0.24 N/A 0.2981 0.4719 424.72 0.00 0.00 0.00 0.00 0.00 424.72 1969.45 41.03 2507.25 1.27 0.00 0.00 13:15 3.4 0.63 0.23 N/A 0.3941 0.6239 561.50 0.00 0.00 0.00 0.00 0.00 561.50 1969.45 41.03 3027.72 1.54 0.00 0.00 13:30 3.4 0.63 0.23 N/A 0.3976 0.6295 566.56 0.00 0.00 0.00 0.00 0.00 566.56 1969.45 41.03 3553.24 1.80 0.00 0.00 13:45 2.3 0.43 0.23 N/A 0.1979 0.3133 281.93 0.00 0.00 0.00 0.00 0.00 281.93 1969.45 41.03 3794.14 1.93 0.00 0.00 14:00 2.3 0.43 0.22 N/A 0.2013 0.3187 286.86 0.00 0.00 0.00 0.00 0.00 286.86 1969.45 41.03 4039.97 2.05 0.00 0.00 14:15 2.7 0.50 0.22 N/A 0.2787 0.4412 397.04 0.00 0.00 0.00 0.00 0.00 397.04 1969.45 41.03 4395.98 2.23 0.00 0.00 14:30 2.6 0.48 0.22 N/A 0.2636 0.4172 375.51 0.00 0.00 0.00 0.00 0.00 375.51 1969.45 41.03 4730.46 2.40 0.00 0.00 14:45 2.6 0.48 0.21 N/A 0.2669 0.4225 380.23 0.00 0.00 0.00 0.00 0.00 380.23 1969.45 41.03 5069.67 2.57 0.00 0.00 15:00 2.5 0.46 0.21 N/A 0.2517 0.3984 358.56 0.00 0.00 0.00 0.00 0.00 358.56 1969.45 41.03 5387.20 2.74 0.00 0.00 15:15 2.4 0.44 0.21 N/A 0.2364 0.3742 336.82 0.00 0.00 0.00 0.00 0.00 336.82 1969.45 41.03 5682.98 2.89 0.00 0.00 15:30 2.3 0.43 0.20 N/A 0.2211 0.3500 315.00 0.00 0.00 0.00 0.00 0.00 315.00 1969.45 41.03 5956.96 3.02 0.00 0.00 15:45 1.9 0.35 0.20 N/A 0.1503 0.2379 214.13 0.00 0.00 0.00 0.00 0.00 214.13 1969.45 41.03 6130.05 3.11 0.00 0.00 16:00 1.9 0.35 0.20 N/A 0.1534 0.2428 218.49 0.00 0.00 0.00 0.00 0.00 218.49 1969.45 41.03 6307.52 3.20 0.00 0.00 PEAK 16:15 0.4 0.07 0.19 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6287.55 3.19 0.00 0.00 16:30 0.4 0.07 0.19 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6267.58 3.18 0.00 0.00 16:45 0.3 0.06 0.19 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6242.35 3.17 0.00 0.00 17:00 0.3 0.06 0.19 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6217.12 3.16 0.00 0.00 17:15 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6202.42 3.15 0.00 0.00 17:30 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6187.72 3.14 0.00 0.00 17:45 0.5 0.09 0.18 0.07 0.0185 0.0293 26.33 0.00 0.00 0.00 0.00 0.00 26.33 1969.45 41.03 6173.02 3.13 0.00 0.00 18:00 0.4 0.07 0.18 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6153.05 3.12 0.00 0.00 18:15 0.4 0.07 0.17 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6133.08 3.11 0.00 0.00 18:30 0.4 0.07 0.17 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6113.12 3.10 0.00 0.00 18:45 0.3 0.06 0.17 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6087.89 3.09 0.00 0.00 19:00 0.2 0.04 0.17 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 6057.39 3.08 0.00 0.00 19:15 0.3 0.06 0.16 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 6032.15 3.06 0.00 0.00 19:30 0.4 0.07 0.16 0.06 0.0148 0.0234 21.06 0.00 0.00 0.00 0.00 0.00 21.06 1969.45 41.03 6012.19 3.05 0.00 0.00 19:45 0.3 0.06 0.16 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5986.96 3.04 0.00 0.00 20:00 0.2 0.04 0.16 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5956.46 3.02 0.00 0.00 20:15 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5931.23 3.01 0.00 0.00 20:30 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5905.99 3.00 0.00 0.00 20:45 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5880.76 2.99 0.00 0.00 21:00 0.2 0.04 0.15 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5850.26 2.97 0.00 0.00 21:15 0.3 0.06 0.15 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5825.03 2.96 0.00 0.00 21:30 0.2 0.04 0.15 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5794.53 2.94 0.00 0.00 21:45 0.3 0.06 0.14 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5769.30 2.93 0.00 0.00 22:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5738.80 2.91 0.00 0.00 22:15 0.3 0.06 0.14 0.04 0.0111 0.0176 15.80 0.00 0.00 0.00 0.00 0.00 15.80 1969.45 41.03 5713.57 2.90 0.00 0.00 22:30 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5683.07 2.89 0.00 0.00 22:45 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5652.57 2.87 0.00 0.00 23:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5622.07 2.85 0.00 0.00 23:15 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5591.58 2.84 0.00 0.00 23:30 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5561.08 2.82 0.00 0.00 23:45 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5530.58 2.81 0.00 0.00 24:00 0.2 0.04 0.14 0.03 0.0074 0.0117 10.53 0.00 0.00 0.00 0.00 0.00 10.53 1969.45 41.03 5500.08 2.79 0.00 0.00 0 0.00 0.14 0.00 0.0000 0.0000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969.45 41.03 5459.05 2.77 0.00 0.00 Total volume (cf)9089.24 Total Overflow (cf)0.00 8/11/2022 PALM DESERT CARMAX BUILDING/PARKING LOT EXPANSION AND CARWASH ADDITION DRAW-DOWN TIME CHECK UNDERGROUND RETENTION BASIN DRAW-DOWN TIME BASIN Total Dead Storage Volume Infiltration Rate Infilitration Safety Factor Design Infiltration Rate (Pdesign) Design Infiltration Rate Used*Total Area Total Infiltration Draw-Down Time -(ft3)(in/hr) - (in/hr) (in/hr) (sf) (cfs) (hrs) A 6,448 5.38 3 1.79 1.00 1,967 0.046 39.34 DRAW DOWN CHECK GOOD * Based on the infiltration rate of 1 in/hr per Palm Desert maximum (with supported testing). 6.85 3/8/2022 6 KTM 3 Sand 0 to 6.85 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 5.22 6.8 18.96 2 25 3.85 6.8 35.4 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 3.40 6.45 36.60 0.27 2 10 3.60 6.12 30.24 0.33 3 10 2.40 5.63 38.76 0.26 4 10 3.13 5.50 28.44 0.35 5 10 2.00 5.32 39.84 0.25 6 10 2.54 5.19 31.80 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 67.78 76.19 64.82 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 113.19 90.64 83.02 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-1 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 64.820.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.51 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  6.75 3/8/2022 6 KTM 3 Sand 0 to 6.75 50+ 0.42 197 5 Initial, Do (ft.)Final, Df (ft.) 1 25 3.6 6.6 36 2 25 2.8 6.6 45.6 Initial, Do (ft.)Final, Df (ft.)(min/in.) 1 10 2.32 5.30 35.76 0.28 2 10 2.68 5.10 29.04 0.34 3 10 2.10 4.82 32.64 0.31 4 10 2.70 4.94 26.88 0.37 5 10 2.43 5.05 31.44 0.32 6 10 2.30 4.99 32.28 0.31 Φ Factor Category B Should Be Provided and Calculated by Project Civil Engineer Ho = DT - Do Hf = DT - Df Reference: 55.78 63.58 63.36 Test Date: Change in Height of Water Greater Than or Equal to 6"? (Yes/No)* SANDY SOIL CRITERIA TEST yes yes PERCOLATION TEST Percolation Rate (gal/day/ft^2) 73.97 61.68 60.59 30Standard Time Interval Between Readings (min.), [* if yes = 10, if no = 30]: Depth from Existing Ground Surface to Bottom of Prop. Inflitration System (ft): Total Depth of Boring, DT (ft): Diameter of Hole, D (in): 0.25 1 0.25 0.25 0.25 1 1 1 r = D / 2 Site Soil Variability Depth to Groundwater / Impervious Layer Soil Assessment Methods Predominant Soil Texture 3186 Airway Avenue, Suite K ΔH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 Tested By: USCS Soil Type: Depth to Groundwater (ft): Ground Elevation (msl ft): Change in Water Level ΔD (in.) FACTOR OF SAFETY WORKSHEET DATE: March, 2022 0.25 0.25 0.25 0.25 1 Palm Desert, California Appendix CJ.N.: 22-178 Costa Mesa, California 92626 PHONE: (714) 549-8921 SARWQCB, Technical Guidance Document Appendix VII, dated December 20, 2013 Factor CategoryΦ Factor Description Assigned Weight (w) Factor Value (v) A Suitability Assessment Suitability Assessment Safety Factor, SA = Σp COSTA MESA TEMECULA LOS ANGELES PALM DESERT CORONA ESCONDIDO PERCOLATION TEST SUMMARY 73450 Dinah Shore Drive PETRA GEOSCIENCES, INC. Product (p) p = (w) x (v) # Where Infiltration Rate, It = ΔH (60r) / Δt (r + 2Havg) **Raw Results. Does Not Include a Factor of Safety Boring/Test Number: P-2 TEST RESULTS** Percolation Rate (gal/day/ft^2)(min/in.) 63.360.31 Inflitration Rate [Porchet Method]# (inches/hour) 5.38 Time Interval Δt (min.) Trial No. Depth to Water, Dw Change in Water Level ΔH (in.) Diameter of Casing, d (in): Depth of Slotted Casing (ft): Trial No. Time Interval Δt (min.) Depth to Water, Dw Porosity of Annulus Material, n : existing ground surface  www.mbakerintl.com 75-410 Gerald Ford Drive, Suite 100 | Palm Desert, CA 92211 Office: 760.346.7481 APPENDIX F ADS UNDERGROUND RETENTION BASIN DESIGN SHEETS User Inputs Chamber Model: MC-3500 Outlet Control Structure: Yes Project Name: 190260 - CarMax Ex- pansion (3 Rows/In- terior Outlet) Engineer: Carmen Graciano Project Location: California Measurement Type: Imperial Required Storage Volume: 6213.17 cubic ft. Stone Porosity: 40% Stone Foundation Depth: 9 in. Stone Above Chambers: 12 in. Average Cover Over Chambers: 18 in. Design Constraint Dimensions:(23 ft. x 116 ft.) Results System Volume and Bed Size Installed Storage Volume: 6448.45 cubic ft. Storage Volume Per Chamber: 109.90 cubic ft. Number Of Chambers Required: 31 Number Of End Caps Required: 8 Chamber Rows: 3 Maximum Length:88.51 ft. Maximum Width: 22.25 ft. Approx. Bed Size Required: 1969.45 square ft. System Components Amount Of Stone Required: 271 cubic yards Volume Of Excavation (Not Including Fill): 402 cubic yards Total Non-woven Geotextile Required:688 square yards Woven Geotextile Required (excluding Isolator Row): 34 square yards Woven Geotextile Required (Isolator Row): 97 square yards Total Woven Geotextile Required:130 square yards Advanced Drainage Systems, Inc.FOR STORMTECHINSTALLATION INSTRUCTIONSVISIT OUR APPSiteAssistMC-3500 STORMTECH CHAMBER SPECIFICATIONS1.CHAMBERS SHALL BE STORMTECH MC-3500.2.CHAMBERS SHALL BE ARCH-SHAPED AND SHALL BE MANUFACTURED FROM VIRGIN, IMPACT-MODIFIED POLYPROPYLENECOPOLYMERS.3.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATEDWALL STORMWATER COLLECTION CHAMBERS" CHAMBER CLASSIFICATION 45x76 DESIGNATION SS.4.CHAMBER ROWS SHALL PROVIDE CONTINUOUS, UNOBSTRUCTED INTERNAL SPACE WITH NO INTERNAL SUPPORTS THAT WOULDIMPEDE FLOW OR LIMIT ACCESS FOR INSPECTION.5.THE STRUCTURAL DESIGN OF THE CHAMBERS, THE STRUCTURAL BACKFILL, AND THE INSTALLATION REQUIREMENTS SHALL ENSURETHAT THE LOAD FACTORS SPECIFIED IN THE AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS, SECTION 12.12, ARE MET FOR: 1)LONG-DURATION DEAD LOADS AND 2) SHORT-DURATION LIVE LOADS, BASED ON THE AASHTO DESIGN TRUCK WITH CONSIDERATIONFOR IMPACT AND MULTIPLE VEHICLE PRESENCES.6.CHAMBERS SHALL BE DESIGNED, TESTED AND ALLOWABLE LOAD CONFIGURATIONS DETERMINED IN ACCORDANCE WITH ASTM F2787,"STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".LOAD CONFIGURATIONS SHALL INCLUDE: 1) INSTANTANEOUS (<1 MIN) AASHTO DESIGN TRUCK LIVE LOAD ON MINIMUM COVER 2)MAXIMUM PERMANENT (75-YR) COVER LOAD AND 3) ALLOWABLE COVER WITH PARKED (1-WEEK) AASHTO DESIGN TRUCK.7.REQUIREMENTS FOR HANDLING AND INSTALLATION:·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKINGSTACKING LUGS.·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESSTHAN 3”.·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BEGREATER THAN OR EQUAL TO 450 LBS/FT/%. THE ASC IS DEFINED IN SECTION 6.2.8 OF ASTM F2418. AND b) TO RESIST CHAMBERDEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCEDFROM REFLECTIVE GOLD OR YELLOW COLORS.8.ONLY CHAMBERS THAT ARE APPROVED BY THE SITE DESIGN ENGINEER WILL BE ALLOWED. UPON REQUEST BY THE SITE DESIGNENGINEER OR OWNER, THE CHAMBER MANUFACTURER SHALL SUBMIT A STRUCTURAL EVALUATION FOR APPROVAL BEFOREDELIVERING CHAMBERS TO THE PROJECT SITE AS FOLLOWS:·THE STRUCTURAL EVALUATION SHALL BE SEALED BY A REGISTERED PROFESSIONAL ENGINEER.·THE STRUCTURAL EVALUATION SHALL DEMONSTRATE THAT THE SAFETY FACTORS ARE GREATER THAN OR EQUAL TO 1.95 FORDEAD LOAD AND 1.75 FOR LIVE LOAD, THE MINIMUM REQUIRED BY ASTM F2787 AND BY SECTIONS 3 AND 12.12 OF THE AASHTOLRFD BRIDGE DESIGN SPECIFICATIONS FOR THERMOPLASTIC PIPE.·THE TEST DERIVED CREEP MODULUS AS SPECIFIED IN ASTM F2418 SHALL BE USED FOR PERMANENT DEAD LOAD DESIGNEXCEPT THAT IT SHALL BE THE 75-YEAR MODULUS USED FOR DESIGN.9.CHAMBERS AND END CAPS SHALL BE PRODUCED AT AN ISO 9001 CERTIFIED MANUFACTURING FACILITY.IMPORTANT - NOTES FOR THE BIDDING AND INSTALLATION OF MC-3500 CHAMBER SYSTEM1.STORMTECH MC-3500 CHAMBERS SHALL NOT BE INSTALLED UNTIL THE MANUFACTURER'S REPRESENTATIVE HAS COMPLETED APRE-CONSTRUCTION MEETING WITH THE INSTALLERS.2.STORMTECH MC-3500 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".3.CHAMBERS ARE NOT TO BE BACKFILLED WITH A DOZER OR AN EXCAVATOR SITUATED OVER THE CHAMBERS.STORMTECH RECOMMENDS 3 BACKFILL METHODS:·STONESHOOTER LOCATED OFF THE CHAMBER BED.·BACKFILL AS ROWS ARE BUILT USING AN EXCAVATOR ON THE FOUNDATION STONE OR SUBGRADE.·BACKFILL FROM OUTSIDE THE EXCAVATION USING A LONG BOOM HOE OR EXCAVATOR.4.THE FOUNDATION STONE SHALL BE LEVELED AND COMPACTED PRIOR TO PLACING CHAMBERS.5.JOINTS BETWEEN CHAMBERS SHALL BE PROPERLY SEATED PRIOR TO PLACING STONE.6.MAINTAIN MINIMUM - 6" (150 mm) SPACING BETWEEN THE CHAMBER ROWS.7.INLET AND OUTLET MANIFOLDS MUST BE INSERTED A MINIMUM OF 12" (300 mm) INTO CHAMBER END CAPS.8.EMBEDMENT STONE SURROUNDING CHAMBERS MUST BE A CLEAN, CRUSHED, ANGULAR STONE MEETING THE AASHTO M43 DESIGNATION OF #3OR #4.9.STONE MUST BE PLACED ON THE TOP CENTER OF THE CHAMBER TO ANCHOR THE CHAMBERS IN PLACE AND PRESERVE ROW SPACING.10.THE CONTRACTOR MUST REPORT ANY DISCREPANCIES WITH CHAMBER FOUNDATION MATERIALS BEARING CAPACITIES TO THE SITE DESIGNENGINEER.11.ADS RECOMMENDS THE USE OF "FLEXSTORM CATCH IT" INSERTS DURING CONSTRUCTION FOR ALL INLETS TO PROTECT THE SUBSURFACESTORMWATER MANAGEMENT SYSTEM FROM CONSTRUCTION SITE RUNOFF.NOTES FOR CONSTRUCTION EQUIPMENT1.STORMTECH MC-3500 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".2.THE USE OF EQUIPMENT OVER MC-3500 CHAMBERS IS LIMITED:·NO EQUIPMENT IS ALLOWED ON BARE CHAMBERS.·NO RUBBER TIRED LOADER, DUMP TRUCK, OR EXCAVATORS ARE ALLOWED UNTIL PROPER FILL DEPTHS ARE REACHED IN ACCORDANCEWITH THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".·WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT CAN BE FOUND IN THE "STORMTECH MC-3500/MC-4500 CONSTRUCTION GUIDE".3.FULL 36" (900 mm) OF STABILIZED COVER MATERIALS OVER THE CHAMBERS IS REQUIRED FOR DUMP TRUCK TRAVEL OR DUMPING.USE OF A DOZER TO PUSH EMBEDMENT STONE BETWEEN THE ROWS OF CHAMBERS MAY CAUSE DAMAGE TO CHAMBERS AND IS NOT AN ACCEPTABLEBACKFILL METHOD. ANY CHAMBERS DAMAGED BY USING THE "DUMP AND PUSH" METHOD ARE NOT COVERED UNDER THE STORMTECH STANDARDWARRANTY.CONTACT STORMTECH AT 1-888-892-2694 WITH ANY QUESTIONS ON INSTALLATION REQUIREMENTS OR WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT.©2022 ADS, INC.PROJECT INFORMATIONADS SALES REPPROJECT NO.ENGINEERED PRODUCTMANAGER190260 - CARMAX EXPANSION (3 ROWS/INTERIOR OUTLET)PALM DESERT, CA StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber System4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF26NOTES•MANIFOLD SIZE TO BE DETERMINED BY SITE DESIGN ENGINEER. SEE TECH NOTE #6.32 FOR MANIFOLD SIZING GUIDANCE.•DUE TO THE ADAPTATION OF THIS CHAMBER SYSTEM TO SPECIFIC SITE AND DESIGN CONSTRAINTS, IT MAY BE NECESSARY TO CUT AND COUPLE ADDITIONAL PIPE TO STANDARD MANIFOLDCOMPONENTS IN THE FIELD.•THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.•THIS CHAMBER SYSTEM WAS DESIGNED WITHOUT SITE-SPECIFIC INFORMATION ON SOIL CONDITIONS OR BEARING CAPACITY. THE SITE DESIGN ENGINEER IS RESPONSIBLE FORDETERMININGTHE SUITABILITY OF THE SOIL AND PROVIDING THE BEARING CAPACITY OF THE INSITU SOILS. THE BASE STONE DEPTH MAY BE INCREASED OR DECREASED ONCE THIS INFORMATION ISPROVIDED.•NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE.CONCEPTUAL ELEVATIONSMAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):12.50MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):6.50MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):6.00MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):6.00MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):6.00TOP OF STONE:5.50TOP OF MC-3500 CHAMBER:4.5012" x 12" TOP MANIFOLD INVERT:2.9524" ISOLATOR ROW PLUS INVERT:0.9218" BOTTOM CONNECTION INVERT:0.90BOTTOM OF MC-3500 CHAMBER:0.75BOTTOM OF STONE:0.00PROPOSED LAYOUT31STORMTECH MC-3500 CHAMBERS8STORMTECH MC-3500 END CAPS12STONE ABOVE (in)9STONE BELOW (in)40STONE VOID6450INSTALLED SYSTEM VOLUME (CF)(PERIMETER STONE INCLUDED)(COVER STONE INCLUDED)(BASE STONE INCLUDED)1969SYSTEM AREA (SF)221.5SYSTEM PERIMETER (ft)*INVERT ABOVE BASE OF CHAMBERMAX FLOWINVERT*DESCRIPTIONITEM ONLAYOUTPART TYPE2.06"24" BOTTOM CORED END CAP, PART#: MC3500IEPP24BC / TYP OF ALL 24" BOTTOMCONNECTIONS AND ISOLATOR PLUS ROWSAPREFABRICATED END CAP26.36"12" TOP CORED END CAP, PART#: MC3500IEPP12T / TYP OF ALL 12" TOP CONNECTIONSBPREFABRICATED END CAP1.77"18" BOTTOM CORED END CAP, PART#: MC3500IEPP18BC / TYP OF ALL 18" BOTTOMCONNECTIONSCPREFABRICATED END CAPINSTALL FLAMP ON 24" ACCESS PIPE / PART#: MC350024RAMPDFLAMP26.36"12" x 12" TOP MANIFOLD, ADS N-12EMANIFOLD5.0 CFS IN30" DIAMETER (24.00" SUMP MIN)FNYLOPLAST (INLET W/ ISOPLUS ROW)4.0 CFS OUT30" DIAMETER (DESIGN BY ENGINEER)GNYLOPLAST (OUTLET)ISOLATOR ROW PLUS(SEE DETAIL)PLACE MINIMUM 17.50' OF ADSPLUS175 WOVEN GEOTEXTILE OVER BEDDINGSTONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALLCHAMBER INLET ROWSBED LIMITS20'10'088.51'22.25'82.58'20.25'EGBCDAF StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemACCEPTABLE FILL MATERIALS: STORMTECH MC-3500 CHAMBER SYSTEMSPLEASE NOTE:1.THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED, ANGULAR NO. 4 (AASHTO M43) STONE".2.STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 9" (230 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR.3.WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTION EQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FORCOMPACTION REQUIREMENTS.4.ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL REQUIREMENTS OF LAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION.NOTES:1.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS" CHAMBER CLASSIFICATION 45x76DESIGNATION SS.2.MC-3500 CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".3.THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE WITH CONSIDERATIONFOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS.4.PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS.5.REQUIREMENTS FOR HANDLING AND INSTALLATION:·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKING STACKING LUGS.·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESS THAN 3”.·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BE GREATER THAN OR EQUAL TO 450 LBS/FT/%. THE ASC IS DEFINED IN SECTION 6.2.8 OFASTM F2418. AND b) TO RESIST CHAMBER DEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCED FROM REFLECTIVE GOLD OR YELLOWCOLORS.MATERIAL LOCATIONDESCRIPTIONAASHTO MATERIALCLASSIFICATIONSCOMPACTION / DENSITY REQUIREMENTDFINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTS FROM THE TOP OF THE 'C'LAYER TO THE BOTTOM OF FLEXIBLE PAVEMENT OR UNPAVED FINISHEDGRADE ABOVE. NOTE THAT PAVEMENT SUBBASE MAY BE PART OF THE 'D'LAYERANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PER ENGINEER'S PLANS.CHECK PLANS FOR PAVEMENT SUBGRADE REQUIREMENTS.N/APREPARE PER SITE DESIGN ENGINEER'S PLANS. PAVEDINSTALLATIONS MAY HAVE STRINGENT MATERIAL ANDPREPARATION REQUIREMENTS.CINITIAL FILL: FILL MATERIAL FOR LAYER 'C' STARTS FROM THE TOP OF THEEMBEDMENT STONE ('B' LAYER) TO 24" (600 mm) ABOVE THE TOP OF THECHAMBER. NOTE THAT PAVEMENT SUBBASE MAY BE A PART OF THE 'C'LAYER.GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35% FINES ORPROCESSED AGGREGATE. MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEU OF THISLAYER.AASHTO M145¹A-1, A-2-4, A-3ORAASHTO M43¹3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89, 9, 10BEGIN COMPACTIONS AFTER 24" (600 mm) OF MATERIAL OVERTHE CHAMBERS IS REACHED. COMPACT ADDITIONAL LAYERS IN12" (300 mm) MAX LIFTS TO A MIN. 95% PROCTOR DENSITY FORWELL GRADED MATERIAL AND 95% RELATIVE DENSITY FORPROCESSED AGGREGATE MATERIALS.BEMBEDMENT STONE: FILL SURROUNDING THE CHAMBERS FROM THEFOUNDATION STONE ('A' LAYER) TO THE 'C' LAYER ABOVE.CLEAN, CRUSHED, ANGULAR STONEAASHTO M43¹3, 4AFOUNDATION STONE: FILL BELOW CHAMBERS FROM THE SUBGRADE UP TOTHE FOOT (BOTTOM) OF THE CHAMBER.CLEAN, CRUSHED, ANGULAR STONEAASHTO M43¹3, 4PLATE COMPACT OR ROLL TO ACHIEVE A FLAT SURFACE.2,345"(1140 mm)18"(450 mm) MIN*8'(2.4 m)MAX12" (300 mm) MIN77" (1950 mm)12" (300 mm) MIN6"(150 mm) MINDEPTH OF STONE TO BE DETERMINEDBY SITE DESIGN ENGINEER 9" (230 mm) MINDCBA*TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVEDINSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR,INCREASE COVER TO 24" (600 mm).6" (150 mm) MINPERIMETER STONE(SEE NOTE 4)EXCAVATION WALL(CAN BE SLOPED OR VERTICAL)MC-3500END CAPSUBGRADE SOILS(SEE NOTE 3)PAVEMENT LAYER (DESIGNEDBY SITE DESIGN ENGINEER)NO COMPACTION REQUIRED.ADS GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE ALLAROUND CLEAN, CRUSHED, ANGULAR STONE IN A & B LAYERS4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF36 StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemINSPECTION & MAINTENANCESTEP 1)INSPECT ISOLATOR ROW PLUS FOR SEDIMENTA.INSPECTION PORTS (IF PRESENT)A.1.REMOVE/OPEN LID ON NYLOPLAST INLINE DRAINA.2.REMOVE AND CLEAN FLEXSTORM FILTER IF INSTALLEDA.3.USING A FLASHLIGHT AND STADIA ROD, MEASURE DEPTH OF SEDIMENT AND RECORD ON MAINTENANCE LOGA.4.LOWER A CAMERA INTO ISOLATOR ROW PLUS FOR VISUAL INSPECTION OF SEDIMENT LEVELS (OPTIONAL)A.5.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.B.ALL ISOLATOR PLUS ROWSB.1.REMOVE COVER FROM STRUCTURE AT UPSTREAM END OF ISOLATOR ROW PLUSB.2.USING A FLASHLIGHT, INSPECT DOWN THE ISOLATOR ROW PLUS THROUGH OUTLET PIPEi)MIRRORS ON POLES OR CAMERAS MAY BE USED TO AVOID A CONFINED SPACE ENTRYii)FOLLOW OSHA REGULATIONS FOR CONFINED SPACE ENTRY IF ENTERING MANHOLEB.3.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.STEP 2)CLEAN OUT ISOLATOR ROW PLUS USING THE JETVAC PROCESSA.A FIXED CULVERT CLEANING NOZZLE WITH REAR FACING SPREAD OF 45" (1.1 m) OR MORE IS PREFERREDB.APPLY MULTIPLE PASSES OF JETVAC UNTIL BACKFLUSH WATER IS CLEANC.VACUUM STRUCTURE SUMP AS REQUIREDSTEP 3)REPLACE ALL COVERS, GRATES, FILTERS, AND LIDS; RECORD OBSERVATIONS AND ACTIONS.STEP 4)INSPECT AND CLEAN BASINS AND MANHOLES UPSTREAM OF THE STORMTECH SYSTEM.NOTES1.INSPECT EVERY 6 MONTHS DURING THE FIRST YEAR OF OPERATION. ADJUST THE INSPECTION INTERVAL BASED ON PREVIOUSOBSERVATIONS OF SEDIMENT ACCUMULATION AND HIGH WATER ELEVATIONS.2.CONDUCT JETTING AND VACTORING ANNUALLY OR WHEN INSPECTION SHOWS THAT MAINTENANCE IS NECESSARY.24" (600 mm) HDPE ACCESS PIPE REQUIREDUSE FACTORY PARTIAL CUT END CAP PART #:MC3500IEPP24BC OR MC3500IEPP24BWONE LAYER OF ADSPLUS175 WOVEN GEOTEXTILE BETWEENFOUNDATION STONE AND CHAMBERS8.25' (2.51 m) MIN WIDE CONTINUOUS FABRIC WITHOUT SEAMSCOVER PIPE CONNECTION TO ENDCAP WITH ADS GEOSYNTHETICS 601TNON-WOVEN GEOTEXTILEMC-3500 CHAMBERMC-3500 END CAPMC-3500 ISOLATOR ROW PLUS DETAILNTSOPTIONAL INSPECTION PORTSTORMTECH HIGHLY RECOMMENDSFLEXSTORM INSERTS IN ANY UPSTREAMSTRUCTURES WITH OPEN GRATESELEVATED BYPASS MANIFOLDINSTALL FLAMP ON 24" (600 mm) ACCESS PIPEPART #: MC350024RAMPSUMP DEPTH TBD BYSITE DESIGN ENGINEER(24" [600 mm] MIN RECOMMENDED)NYLOPLAST4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF46 StormTech888-892-2694 | WWW.STORMTECH.COM®Chamber SystemMC-SERIES END CAP INSERTION DETAILNTSNOTE: MANIFOLD STUB MUST BE LAID HORIZONTALFOR A PROPER FIT IN END CAP OPENING.MANIFOLD HEADERMANIFOLD STUBSTORMTECH END CAPMANIFOLD HEADERMANIFOLD STUB12" (300 mm)MIN SEPARATION12" (300 mm) MIN INSERTION12" (300 mm)MIN SEPARATION12" (300 mm)MIN INSERTIONPART #STUBBCMC3500IEPP06T6" (150 mm)33.21" (844 mm)---MC3500IEPP06B---0.66" (17 mm)MC3500IEPP08T8" (200 mm)31.16" (791 mm)---MC3500IEPP08B---0.81" (21 mm)MC3500IEPP10T10" (250 mm)29.04" (738 mm)---MC3500IEPP10B---0.93" (24 mm)MC3500IEPP12T12" (300 mm)26.36" (670 mm)---MC3500IEPP12B---1.35" (34 mm)MC3500IEPP15T15" (375 mm)23.39" (594 mm)---MC3500IEPP15B---1.50" (38 mm)MC3500IEPP18TC18" (450 mm)20.03" (509 mm)---MC3500IEPP18TWMC3500IEPP18BC---1.77" (45 mm)MC3500IEPP18BWMC3500IEPP24TC24" (600 mm)14.48" (368 mm)---MC3500IEPP24TWMC3500IEPP24BC---2.06" (52 mm)MC3500IEPP24BWMC3500IEPP30BC30" (750 mm)---2.75" (70 mm)NOMINAL CHAMBER SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)77.0" X 45.0" X 86.0" (1956 mm X 1143 mm X 2184 mm)CHAMBER STORAGE109.9 CUBIC FEET (3.11 m³)MINIMUM INSTALLED STORAGE*175.0 CUBIC FEET (4.96 m³)WEIGHT134 lbs.(60.8 kg)NOMINAL END CAP SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)75.0" X 45.0" X 22.2" (1905 mm X 1143 mm X 564 mm)END CAP STORAGE14.9 CUBIC FEET (0.42 m³)MINIMUM INSTALLED STORAGE*45.1 CUBIC FEET (1.28 m³)WEIGHT49 lbs.(22.2 kg)*ASSUMES 12" (305 mm) STONE ABOVE, 9" (229 mm) STONE FOUNDATION, 6" SPACING BETWEENCHAMBERS, 6" (152 mm) STONE PERIMETER IN FRONT OF END CAPS AND 40% STONE POROSITYMC-3500 TECHNICAL SPECIFICATIONNTS90.0" (2286 mm)ACTUAL LENGTH86.0" (2184 mm)INSTALLEDBUILD ROW IN THIS DIRECTIONNOTE: ALL DIMENSIONS ARE NOMINALLOWER JOINTCORRUGATIONWEBCRESTCRESTSTIFFENING RIBVALLEYSTIFFENING RIBBC75.0"(1905 mm)45.0"(1143 mm)25.7"(653 mm)FOOT77.0"(1956 mm)45.0"(1143 mm)STUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"END CAPS WITH A WELDED CROWN PLATE END WITH "C"END CAPS WITH A PREFABRICATED WELDED STUB END WITH "W"UPPER JOINT CORRUGATION22.2"(564 mm)INSTALLEDCUSTOM PRECORED INVERTS AREAVAILABLE UPON REQUEST.INVENTORIED MANIFOLDS INCLUDE12-24" (300-600 mm) SIZE ON SIZEAND 15-48" (375-1200 mm)ECCENTRIC MANIFOLDS. CUSTOMINVERT LOCATIONS ON THE MC-3500END CAP CUT IN THE FIELD ARE NOTRECOMMENDED FOR PIPE SIZESGREATER THAN 10" (250 mm). THEINVERT LOCATION IN COLUMN 'B'ARE THE HIGHEST POSSIBLE FORTHE PIPE SIZE.PART #STUBBCMC3500IEPP06T6" (150 mm)33.21" (844 mm)---MC3500IEPP06B---0.66" (17 mm)MC3500IEPP08T8" (200 mm)31.16" (791 mm)---MC3500IEPP08B---0.81" (21 mm)MC3500IEPP10T10" (250 mm)29.04" (738 mm)---MC3500IEPP10B---0.93" (24 mm)MC3500IEPP12T12" (300 mm)26.36" (670 mm)---MC3500IEPP12B---1.35" (34 mm)MC3500IEPP15T15" (375 mm)23.39" (594 mm)---MC3500IEPP15B---1.50" (38 mm)MC3500IEPP18TC18" (450 mm)20.03" (509 mm)---MC3500IEPP18TWMC3500IEPP18BC---1.77" (45 mm)MC3500IEPP18BWMC3500IEPP24TC24" (600 mm)14.48" (368 mm)---MC3500IEPP24TWMC3500IEPP24BC---2.06" (52 mm)MC3500IEPP24BWMC3500IEPP30BC30" (750 mm)---2.75" (70 mm)NOMINAL CHAMBER SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)77.0" X 45.0" X 86.0" (1956 mm X 1143 mm X 2184 mm)CHAMBER STORAGE109.9 CUBIC FEET (3.11 m³)MINIMUM INSTALLED STORAGE*175.0 CUBIC FEET (4.96 m³)WEIGHT134 lbs.(60.8 kg)NOMINAL END CAP SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)75.0" X 45.0" X 22.2" (1905 mm X 1143 mm X 564 mm)END CAP STORAGE14.9 CUBIC FEET (0.42 m³)MINIMUM INSTALLED STORAGE*45.1 CUBIC FEET (1.28 m³)WEIGHT49 lbs.(22.2 kg)*ASSUMES 12" (305 mm) STONE ABOVE, 9" (229 mm) STONE FOUNDATION, 6" SPACING BETWEENCHAMBERS, 6" (152 mm) STONE PERIMETER IN FRONT OF END CAPS AND 40% STONE POROSITYMC-3500 TECHNICAL SPECIFICATIONNTS90.0" (2286 mm)ACTUAL LENGTH86.0" (2184 mm)INSTALLEDBUILD ROW IN THIS DIRECTIONNOTE: ALL DIMENSIONS ARE NOMINALLOWER JOINTCORRUGATIONWEBCRESTCRESTSTIFFENING RIBVALLEYSTIFFENING RIBBC75.0"(1905 mm)45.0"(1143 mm)25.7"(653 mm)FOOT77.0"(1956 mm)45.0"(1143 mm)STUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"END CAPS WITH A WELDED CROWN PLATE END WITH "C"END CAPS WITH A PREFABRICATED WELDED STUB END WITH "W"UPPER JOINT CORRUGATION22.2"(564 mm)INSTALLEDCUSTOM PRECORED INVERTS AREAVAILABLE UPON REQUEST.INVENTORIED MANIFOLDS INCLUDE12-24" (300-600 mm) SIZE ON SIZEAND 15-48" (375-1200 mm)ECCENTRIC MANIFOLDS. CUSTOMINVERT LOCATIONS ON THE MC-3500END CAP CUT IN THE FIELD ARE NOTRECOMMENDED FOR PIPE SIZESGREATER THAN 10" (250 mm). THEINVERT LOCATION IN COLUMN 'B'ARE THE HIGHEST POSSIBLE FORTHE PIPE SIZE.4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF56 NYLOPLAST DRAIN BASINNTSNOTES1.8-30" (200-750 mm) GRATES/SOLID COVERS SHALL BE DUCTILE IRON PER ASTM A536GRADE 70-50-052.12-30" (300-750 mm) FRAMES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-053.DRAIN BASIN TO BE CUSTOM MANUFACTURED ACCORDING TO PLAN DETAILS4.DRAINAGE CONNECTION STUB JOINT TIGHTNESS SHALL CONFORM TO ASTM D3212FOR CORRUGATED HDPE (ADS & HANCOR DUAL WALL) & SDR 35 PVC5.FOR COMPLETE DESIGN AND PRODUCT INFORMATION: WWW.NYLOPLAST-US.COM6.TO ORDER CALL: 800-821-6710APART #GRATE/SOLID COVER OPTIONS8"(200 mm)2808AGPEDESTRIAN LIGHTDUTYSTANDARD LIGHTDUTYSOLID LIGHT DUTY10"(250 mm)2810AGPEDESTRIAN LIGHTDUTYSTANDARD LIGHTDUTYSOLID LIGHT DUTY12"(300 mm)2812AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2015"(375 mm)2815AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2018"(450 mm)2818AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2024"(600 mm)2824AGPEDESTRIANAASHTO H-10STANDARD AASHTOH-20SOLIDAASHTO H-2030"(750 mm)2830AGPEDESTRIANAASHTO H-20STANDARD AASHTOH-20SOLIDAASHTO H-20INTEGRATED DUCTILE IRONFRAME & GRATE/SOLID TOMATCH BASIN O.D.VARIOUS TYPES OF INLET ANDOUTLET ADAPTERS AVAILABLE:4-30" (100-750 mm) FORCORRUGATED HDPEWATERTIGHT JOINT(CORRUGATED HDPE SHOWN)BACKFILL MATERIAL BELOW AND TO SIDESOF STRUCTURE SHALL BE ASTM D2321CLASS I OR II CRUSHED STONE OR GRAVELAND BE PLACED UNIFORMLY IN 12" (305 mm)LIFTS AND COMPACTED TO MIN OF 90%TRAFFIC LOADS: CONCRETE DIMENSIONSARE FOR GUIDELINE PUPOSES ONLY.ACTUAL CONCRETE SLAB MUST BEDESIGNED GIVING CONSIDERATION FORLOCAL SOIL CONDITIONS, TRAFFIC LOADING& OTHER APPLICABLE DESIGN FACTORSADAPTER ANGLES VARIABLE 0°- 360°ACCORDING TO PLANS18" (457 mm)MIN WIDTHAAASHTO H-20 CONCRETE SLAB8" (203 mm) MIN THICKNESSVARIABLE SUMP DEPTHACCORDING TO PLANS[6" (152 mm) MIN ON 8-24" (200-600 mm),10" (254 mm) MIN ON 30" (750 mm)]4" (102 mm) MIN ON 8-24" (200-600 mm)6" (152 mm) MIN ON 30" (750 mm)12" (610 mm) MIN(FOR AASHTO H-20)INVERT ACCORDING TOPLANS/TAKE OFFNyloplast770-932-2443 | WWW.NYLOPLAST-US.COM®4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473DATE: DRAWN: CGPROJECT #: CHECKED: N/ATHIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.DATEDRWCHKDESCRIPTION190260 - CARMAX EXPANSION (3ROWS/INTERIOR OUTLET)PALM DESERT, CASHEETOF66 www.mbakerintl.com APPENDIX G RATIONAL METHOD CALCULATIONS GRATE SIZING CALCULATIONS JENSEN BROOKS 3636 CB GRATE INLET DETAILS SHEET JENSEN BROOKS 2424 CB GRATE INLET DETAILS SHEET Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 08/10/22 File:190260RAT100EXIST3DMA.out ------------------------------------------------------------------------ PROPOSED CARMAX EXPANSION 100-YR DESIGN STORM RATIONAL METHOD CALCULATION BY CARMEN GRACIANO ON 8-10-2022 ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Program License Serial Number 6341 ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 2 Standard intensity-duration curves data (Plate D-4.1) For the [ Cathedral City ] area used. 10 year storm 10 minute intensity = 2.770(In/Hr) 10 year storm 60 minute intensity = 0.980(In/Hr) 100 year storm 10 minute intensity = 4.520(In/Hr) 100 year storm 60 minute intensity = 1.600(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.600(In/Hr) Slope of intensity duration curve = 0.5800 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 10.000 to Point/Station 20.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 358.580(Ft.) Top (of initial area) elevation = 204.000(Ft.) Bottom (of initial area) elevation = 200.280(Ft.) Difference in elevation = 3.720(Ft.) Slope = 0.01037 s(percent)= 1.04 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 7.866 min. Rainfall intensity = 5.199(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.868 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 4.017(CFS) Total initial stream area = 0.890(Ac.) Pervious area fraction = 0.100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 30.000 to Point/Station 40.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 193.980(Ft.) Top (of initial area) elevation = 202.990(Ft.) Bottom (of initial area) elevation = 200.850(Ft.) Difference in elevation = 2.140(Ft.) Slope = 0.01103 s(percent)= 1.10 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 6.077 min. Rainfall intensity = 6.038(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.871 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 0.842(CFS) Total initial stream area = 0.160(Ac.) Pervious area fraction = 0.100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 50.000 to Point/Station 60.000 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 228.270(Ft.) Top (of initial area) elevation = 203.060(Ft.) Bottom (of initial area) elevation = 200.080(Ft.) Difference in elevation = 2.980(Ft.) Slope = 0.01305 s(percent)= 1.31 TC = k(0.300)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 6.271 min. Rainfall intensity = 5.929(In/Hr) for a 100.0 year storm COMMERCIAL subarea type Runoff Coefficient = 0.871 Decimal fraction soil group A = 1.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 2) = 32.00 Pervious area fraction = 0.100; Impervious fraction = 0.900 Initial subarea runoff = 2.633(CFS) Total initial stream area = 0.510(Ac.) Pervious area fraction = 0.100 End of computations, total study area = 1.56 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 0.100 Area averaged RI index number = 32.0 Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 20 - 36X36 - Q=4.017 CFS @ 0.50% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.005 Slope, Sx (ft/ft) = 0.005 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.02 Highlighted Q Total (cfs) = 4.02 Q Capt (cfs) = 4.02 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.78 Efficiency (%) = 100 Gutter Spread (ft) = 95.69 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 20 - 36X36 - Q=4.017 CFS @ 1.79% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.018 Slope, Sx (ft/ft) = 0.018 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.02 Highlighted Q Total (cfs) = 4.02 Q Capt (cfs) = 4.02 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.78 Efficiency (%) = 100 Gutter Spread (ft) = 28.75 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 40 - 24X24 - Q=0.842 CFS @ 1.05% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 2.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.011 Slope, Sx (ft/ft) = 0.011 Local Depr (in) = -0- Gutter Width (ft) = 2.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.84 Highlighted Q Total (cfs) = 0.84 Q Capt (cfs) = 0.84 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.28 Efficiency (%) = 100 Gutter Spread (ft) = 21.46 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 60 -36X36 - Q=2.633 CFS @ 0.60% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.006 Slope, Sx (ft/ft) = 0.006 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.63 Highlighted Q Total (cfs) = 2.63 Q Capt (cfs) = 2.63 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.10 Efficiency (%) = 100 Gutter Spread (ft) = 61.25 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Aug 10 2022 NODE 60 -36X36 - Q=2.633 CFS @ 1.05% Drop Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.50 Grate Width (ft) = 3.00 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.011 Slope, Sx (ft/ft) = 0.011 Local Depr (in) = -0- Gutter Width (ft) = 3.00 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.63 Highlighted Q Total (cfs) = 2.63 Q Capt (cfs) = 2.63 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.10 Efficiency (%) = 100 Gutter Spread (ft) = 34.75 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- ORG. DWG. DATE REV. DWG. DATE BROOKS 3636 CB 36” x 36” CATCH BASIN 11-23-99 02-14-20 7 - 0 6 3636 FRAME ONLY 3636 BOTTOM SECTION ()NO FRAME 3636 E6 3636 E12 12" 6" 1050 525 NONE EXTENSION SECTION HT.LBS KNOCK-OUTS 3636 B36 36"() 30” DIA.4 BOTTOM SECTION HT.LBS KNOCK-OUTS 2,230 41” 6" 6" 44"44" SEE CHART 4" 36” 3636 STEEL COVER - 1 Pc. PARKWAY TRAFFIC 3636 STEEL GRATES - 2 Pc. TRAFFIC 152 lbs. 190 lbs. 3 1/4"35 7/8" 40 1/4" 35 7/8"40 1/4” NOTES: 1.GRATES AND COVERS AVAILABLE PAINTED BLACK OR GALVANIZED 3.BOLT DOWN GRATES AND COVERS ARE AVAILABLE 2.“ADA” OR “HEEL-PROOF” GRATES ARE FOR THIS SERIESNOT AVAILABLE 3636 STEEL GRATES - 1 Pc. PARKWAY 3 1/4" 35 7/8" 40 1/4" NONE 3636 EXTENSION ()NO FRAME 44"44" 36"40 1/2" 4ea. 30” dia. THINWALL KNOCK-OUTS 36"36" 36"36"341 lbs. 93 lbs. ORG. DWG. DATE REV. DWG. DATE 24” x 24” CATCH BASIN 11-23-99 02-14-20 7 - 0 5 2424 TOP SECTION ()WITH GALVANIZED FRAME 48 lbs. 103 lbs. 2424 STEEL COVER PARKWAY TRAFFIC 2424 LOWER SECTION ()NO FRAME 2424 STEEL GRATES PARKWAY TRAFFIC 81 lbs. 114 lbs. 2424 CAST IRON GRATE PARKWAY 112 lbs. 2424 E6 2424 L12 2424 T12 2424 L18 2424 L24 2424 T18 2424 T24 12" 18" 24" 18" 24" 6" 12" 495 745 870 745 870 270 495 () 6” x 11”4 () 9" x 12"4 () 14" x 14"4 () 9" x 12"4 () 14" x 14"4 NONE () 6" x 11"4 EXTENSION SECTION LOWER SECTION HT. HT. LBS LBS KNOCK-OUTS KNOCK-OUTS 2424 B30 2424 B36 36" 30" 1905 1595 () 18" x 18"4 () 18" x 18"4 BOTTOM SECTION HT.LBS KNOCK-OUTS SEE CHART SEE CHART 34"34" SEE CHART 2 1/4" 26" 26" 26 1/4"26 1/4" 24"24" 2424 BOTTOM SECTION ()WITH OR WITHOUT FRAME 24"24" 34"34" BROOKS 2424 CB NOTES: 1.GRATES AND COVERS AVAILABLE PAINTED BLACK OR GALVANIZED 2.PARKWAY & TRAFFIC . 3.“HEEL PROOF” GRATES AVAILABLE IN 4.A TOP SECTION WITH FRAME MUST BE USED IF BOLT DOWN REQUIRED “ADA” GRATES AVAILABLE IN PARKWAY ONLY 2424 T6 6"270 NONE TOP SECTION HT.LBS KNOCK-OUTS 5" 5" 24"24" 4" NOTE:USE 12”, 18”, 24” LOWERS TO INCREASE DEPTH UP TO A MAXIMUM OF 72” CarMax - Store No. [6113] Drainage Study, 2017 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix G AGREEMENTS – CC&RS, COVENANT AND AGREEMENTS, BMP MAINTENANCE AGREEMENTS AND/OR OTHER MECHANISMS FOR ENSURING ONGOING OPERATION, MAINTENANCE, FUNDING AND TRANSFER OF REQUIREMENTS FOR THIS PROJECT-SPECIFIC WQMP To be provided in Final WQMP 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix H PHASE 1 ENVIRONMENTAL SITE ASSESSMENT – SUMMARY OF SITE REMEDIATION CONDUCTED AND USE RESTRICTIONS NOT APPLICABLE 2014 Whitewater River Region WQMP CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Appendix I PROJECT-SPECIFIC WQMP SUMMARY DATA FORM Project-Specific WQMP Summary Data Form Applicant Information Name and Title Josh Abig, Store Delivery and Support Services Company CarMax Auto Superstores, Inc. Phone (804) 747-0422 x 4237 Email Josh_abig@carmax.com Project Information Project Name (as shown on project application/project-specific WQMP) CarMax Auto Superstore No. 6113 Building/Parking Lot Expansion and Carwash Addition Street Address 73-450 and 73-500 Dinah Shore Drive Nearest Cross Streets Dinah Shore Drive and Gateway Drive Municipality (City or Unincorporated County) City of Palm Desert Zip Code 92211 Tract Number(s) and/or Assessor Parcel Number(s) 694-060-034 and 694-060-036 Other (other information to help identify location of project) Indicate type of project. Priority Development Projects (Use an "X" in cell preceding project type): SF hillside residence; impervious area ≥ 10,000 sq. ft.; Slope ≥ 25% SF hillside residence; impervious area ≥ 10,000 sq. ft.; Slope ≥ 10% & erosive soils Commercial or Industrial ≥ 100,000 sq. ft. Automotive repair shop Retail Gasoline Outlet disturbing > 5,000 sq. ft. Restaurant disturbing > 5,000 sq. ft. Home subdivision ≥ 10 housing units X Parking lot ≥ 5,000 sq. ft. or ≥ 25 parking spaces Date Project-Specific WQMP Submitted Size of Project Area (nearest 0.1 acre) 2.2 acres Will the project replace more than 50% of the impervious surfaces on an existing developed site? No. Land currently vacant with desert shrubbery and sand with approximately 0.12 acres of a paved exit road. Project Area managed with LID/Site Design BMPs (nearest 0.1 acre) 2.2 acres Are Treatment Control BMPs required? No Is the project subject to onsite retention by ordinance or policy? Yes Did the project meet the 100% LID/Site Design Measurable Goal? Yes Name of the entity that will implement, operate, and maintain the post-construction BMPs CarMax Auto Superstores, Inc. Contact Name Josh Abig Street or Mailing Address 12800 Tuckahoe Creek Parkway City Richmond, VA Zip Code 23238 Phone (804) 747-0422 x 4237 Space Below for Use by City/County Staff Only Preceding Information Verified by (consistent with information in project-specific WQMP) Name: Date: Date Project-Specific WQMP Approved: Data Entered by Name: Date: Other Comments CarMax Auto Superstore Expansion – Expanded Statement of Use for submittal with the Conditional Use Permit Application The proposed development consists of expansion and improvements to the existing CarMax Auto Super Store located at 73-500 Dinah Shore in the city of Palm Desert, within Riverside County. Improvements to the auto dealership comprise of expanding the 4.23-acre site to include a 1.9-acre expansion site adjacent west for a new acreage sales staging area. The Staging area expansion is an overflow lot where vehicles will be staged and stored for processing and service by CarMax. Presently, there is an existing staging area behind the CarMax building being utilized for the same purpose. Striping is not applied to the finish surface as most cars are parked in parallel but changes as new inventory arrives to the site, (See attached Images at three (3) of our locations that have the same type of situation.) Employees still park the cars in a manner that allows them access to the lot as necessary daily. The lot will be screened from public view by means of a 6’ high masonry split face block wall that includes a 2” cap and will match the existing wall presently constructed on the easterly lot. Associated improvements include expansion of 2,325 square feet to the existing 6,841 SF sales building; constructing a 923 square foot carwash; and adding 55 parking spaces to the customer/employee parking lot. (Refer to included Site Plan). A Parcel Map Waiver is also being applied for to merge the two contiguous lots into one overall parcel. Both parcels are owned by the same entity. Truck deliveries estimated volume is about 20-25 delivery trucks per week. · Total Number of current associates: Currently: 54 total · Number of associates at one time at the store: roughly 41 · Total Number of associates anticipated after building expansion: 60-day target of 11 more associates The hours of operation will continue to be as follows: Showroom: Monday through Friday 10am to 9pm, Saturday, 9am to 9pm and Sunday 12pm to 7pm. Service: Monday through Friday 7:30am to 6pm. Project Characteristic Existing Proposed Site Acreage 4.23 acres Existing + 1.90 acres = 6.13 acres Sales Building (square feet “SF”) 6,841 SF Existing + 2,325 SF = 9,178 SF Car Wash not applicable 923 SF Number of Employees 54 65 Customer and Employee Parking Spaces East of Main Site Driveway 0 0 West of Main Site Driveway 46 46 + 55 = 101 Total 46 101 Sales Parking Spaces East of Main Site Driveway 145 145 – 9 = 136 West of Main Site Driveway 0 176 Total 145 312 Sales Staging (Existing CarMax - Palm Desert site) Sales Staging (Existing Site) Sales Staging (existing site) 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 11/17/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132VICINITY MAPOWNER ARCHITECTAPPLICANTPROJECT DATALEGEND 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 12/07/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 12/07/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 12/07/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 11/09/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132 75410 GERALD FORD DRIVE, STE. 100, PALM DESERT, CA. 92211760-346-7481"NOT FOR CONSTRUCTION"REVISED: 11/09/2022CIVILSTATE OF CALI FOR NIA R EG ISTERE D P ROFESSIONAL ENGINEERJOHN D . TANNER IIINo. 60132 EVEVEVEVEVEVEVEVEVGHGCAVCAVCAVCAVCAVCAV CAV CAV CAV CAV CAV CAVR:R:E;ISTING C2NC DRAINAGE CHANNELR:SALES STAGING SPACESNE: CE PAR.ING SPACESE;IST CE PAR.ING SPACESE;IST CAR0A;                         E;ISTING LANDSCAPING PERCAR0A; PARCEL A PR2-ECTALIGN :ITH E;ISTINGLANDSCAPINGALIGN :ITH E;ISTINGLANDSCAPINGE;ISTING LANDSCAPING PERCAR0A; PARCEL A PR2-ECTALIGN :ITH E;ISTINGLANDSCAPINGTREES%2TANICAL NA0E C2002N NA0ESI=E4T< :ATER 8SE ACACIA SALIGNAG2LDEN :REATH :ATTLE%2;L2: PAR.INS2NIA )L2RIDA %L8E PAL2 VERDE%2;L2: PR2S2PIS GLAND8L2SAH2NE< 0ES48ITE%2;L2:N2TE  TREE PER  NE: CE PAR.ING SPACES  PAR.ING L2T TREES T2TAL SHR8%S%2TANICAL NA0EC2002N NA0ESI=E4T<:ATER 8SE ACACIA RED2LENS CDESERT CARPETC DESERT CARPET GALL2: AGAVE PARR<IPARR< S AGAVE GALL2:%ACCHARIS ; CTH20PS2NC%ACCHARIS GALL2:CALLISTE02N LITTLE -2HN D:AR) %2TTLE%R8SH GAL0EDI80CHR<SACTINIA 0E;ICANA DA0IANITA GALL2:C8PHEA LLAVEA %AT)ACE %AT)ACED C8PHEA GAL0EDI80DALEA CAPITATA CSIERRA G2LDC SIERRA G2LD DALEA GAL0EDI80 DALEA )R8TESCENS CSIERRA NEGRAC%LAC. PRAIRIE CL2VER GALL2: DALEA GREGGII TRAILING INDIG2 %8SH GALL2:DAS<LIRI2N :HEELERIGRE< DESERT SP22N GALL2:ENCELIA )ARIN2SA%RITTLE %8SH GALL2: HESPERAL2E PARVI)L2RA RED <8CCA GALL2:LANTANA 02NTEVIDENSISTRAILING LANTANA GAL0EDI80 LE8C2PH<LL80 =<G2PH<LL80 C%L8E RANGERC CI00ER2N GALL2:0ELA0P2DI80 LE8CANTH80%LAC.)22T DAIS< GALL2:R8ELLIA PENINS8LARIS:ILD PET8NIA GALL2:SALVIA GREGGII SIERRA LINDA A8T80N SAGE GAL0EDI80 TEC20A STANS <ELL2: %ELLS GAL0EDI80TEC20A STANS VAR ANG8STATA<ELL2: %ELLS ESPERAN=A GAL0EDI80:EDELIA TRIL2%ATA :EDELIA GAL0EDI80<8CCA :HIPPLEICHAPARRAL <8CCA GALL2: DESCRIPTI2N 4T< DEC20P2SED GRANITE  0IN8S DEC20P2SED GRANITE TAN S)PAL0 SPRINGS G2LD T2 0ATCH E;ISTING :  )INES :ETTED AND C20PACTEDT2 )INAL  DEPTHR2C. 08LCH   R28ND RIVER R2C. 08LCH S)ARI=2NA C2%%LE T2 0ATCH E;ISTING )R20 S28TH:EST %28LDER AND ST2NE%28LDERS T\S    DIA0ETER DESERT SAND T2 0ATCH E;ISTING )R20 S28TH:EST %28LDERAND ST2NEPLANTING LEGENDHARDSCAPE LEGENDLANDSCAPE C2NCEPT PLAN  CAR0A; PAR.ING L2T E;PANSI2NIQ WKH CLW\ RI PDOP DHVHUW CRXQW\ RI RLYHUVLGH SWDWH RI CDOLIRUQLDLANDSCAPE C2NCEPT PLANSHEETSHEETSCIT< 2) PAL0 DESERTCAR0A; A8T2 S8PERST2RE N2  GERALD )2RD DRIVE STE  PAL0 DESERT CA "NOT FOR CONSTRUCTION"REVISED PDUFHOV A DQG % RI CHUWLILFDWH RI CRPSOLDQFH P0: CAR0A; PAR.ING L2T E;PANSI2NPDUFHO % RI CHUWLILFDWH RI CRPSOLDQFH P0: N2TESPERCENTAGE 2) NE: LANDSCAPING :ITHIN PAR.ING L2T PERCENTAGE 2) NE: LANDSCAPING IN PERI0ETER 2) PAR.ING L2T A8T20ATIC IRRIGATI2N S<STE0THE IRRIGATI2N SHALL %E )8LL< A8T20ATIC ELECTR2NICALL< C2NTR2LLED PER0ANENT %EL2:GRADE S<STE0 THATC20PLIES :ITH THE CIT< 2) PAL0 DESERT :ATER E))ICIENT LANDSCAPE 2RDINANCE THE S<STE0 SHALL 8SE DRIPIRRIGATI2N A 0ASTER VALVE A )L2:SENS2R A RAIN SENS2R AND A :EATHER %ASED S0ART IRRIGATI2N C2NTR2LLERT2 PR202TE :ATER C2NSERVATI2N1 F.F.E. 0" T.O.M. SERVICE 18' -8" T.O.M. PRES 15' -4" T.O. CANOPY 29' -4" T.O.S. SALES 21' -8" T.O.S. SALES 21' -8" STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE STUCCO; LIGHT EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXTERIOR LIGHTING; BLACK, TYP STUCCO; DARK EARTHTONE PRE-FINISHED METAL SOLAR SHADE; ALUMINUM EXISTING ADDITION ACM PANEL; WHITE STOREFRONT FRAMING; ANNOD. ALUMN. STUCCO; LIGHT EARTHTONE F.F.E. 0" T.O.M. PRES 15' -4" T.O. CANOPY 29' -4" T.O.S. SALES 21' -8" ACM PANEL; WHITE STOREFRONT FRAMING; ANNOD. ALUMN. BLUE-TINTED GLAZING GLAZING; TO MATCH EXIST. STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXISTINGADDITION F.F.E. 0" T.O.M. SERVICE 18' -8" T.O. CANOPY 29' -4" T.O.S. SALES 21' -8" PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE STUCCO; LIGHT EARTHTONE PRE-FINISHED METAL SOLAR SHADE; ALUMINUM EXISTINGADDITION 2' - 0" ADDITION 28' - 3 7/8" EXISTING 30' - 3 5/8" ACM PANEL; WHITE STOREFRONT FRAMING; ANNOD. ALUMN. BLUE-TINTED GLAZING GLAZING; TO MATCH EXIST. STUCCO; MEDIUM EARTHTONE STUCCO; DARK EARTHTONE F.F.E. 0" T.O.M. SERVICE 18' -8" T.O.M. PRES 15' -4" T.O. CANOPY 29' -4" T.O.S. SALES 21' -8" STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE STUCCO; LIGHT EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXTERIOR LIGHTING; BLACK, TYP STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXTERIOR LIGHTING; BLACK, TYP STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXTERIOR LIGHTING; BLACK, TYP STUCCO; MEDIUM EARTHTONE PRE-FINISHED COPING; DARK EARTHTONE INTEGRAL COLOR SPLIT FACE CMU; DARK EARTHTONE EXTERIOR LIGHTING; BLACK, TYP STUCCO; MEDIUM EARTHTONE THE AUTO SUPERSTORE IN ASSOCIATION WITH PIEPER O'BRIEN HERR ARCHITECTS A 3.0PALM DESERT - SALES EXPANSION STORE NO. 6113 - 73-450 DINAH SHORE DRIVE- PALM DESERT, CA 92211 CONCEPTUAL ELEVATIONS20-22031.00 07 DEC 2022 CARMAX THE AUTO SUPERSTORE WEST COAST, INC. 12800 TUCKAHOE CREEK PKWY. RICHMOND, VA 23238 (804) 747-0422 1/8" = 1'-0"A 3.0 1 SOUTH ELEVATION (EXISTING AND NEW) 1/8" = 1'-0"A 3.0 2 WEST ELEVATION (EXISTING) 1/8" = 1'-0"A 3.0 3 EAST ELEVATION (EXISTING AND NEW) 1/8" = 1'-0"A 3.0 4 NORTH ELEVATION (EXISTING) 1/8" = 1'-0"A 3.0 6 SOUTH ELEVATION - CARWASH 1/8" = 1'-0"A 3.0 5 EAST ELEVATION - CARWASH 1/8" = 1'-0"A 3.0 7 NORTH ELEVATION - CARWASH 1/8" = 1'-0"A 3.0 8 WEST ELEVATION - CARWASH EXISTING SALES EXISTING SERVICE SALES ADDITION 18'-8" T.O. NEW PARAPET 21'-8" T.O. NEW PARAPET RD SRD 16'-0" J.B.E. 16'-0" J.B.E. 16'-8" J.B.E. 16'-8" J.B.E. RD SRD 18'-8" T.O. EXISTING PARAPET. 18'-8" T.O. NEW PARAPET 18'-8" T.O. NEW PARAPET 21'-8" T.O. EXISTING PARAPET EXISTING SCREEN WALL AND MECH. UNITS EXISTING MECH. UNITS 21'-8" T.O. EXISTING PARAPET EXISTING ENTRY CANOPY ROOF EXISTING ENTRY CANOPY ROOF 21'-8" T.O. EXISTING PARAPET EXISTING SUNSHADE 15'-4" T.O. EXISTING PARAPET 21'-8" T.O. EXISTING PARAPET EXISTING FALSE ENTRY CANOPY ROOF 18'-8" T.O. EXISTING PARAPET. EXISTING CANOPY BELOW NEW SUNSHADES TO MATCH EXISTING1/4" / 1'-0"1/4" / 1'-0"NEW MECH. UNITS FOR ADDITION EXISTING SCUPPER AND DOWNSPOUT EXISTING SCUPPER AND DOWNSPOUT 16'-8" J.B.E. 16'-8" J.B.E. 14'-10" J.B.E. 14'-10" J.B.E. EXISITING ROOF HATCH 1/4" / 1'-0"1/4" / 1'-0"15'-4" T.O. NEW PARAPET NEW SCUPPER AND DOWNSPOUT TO MATCH EXISTING 21'-8" T.O. NEW PARAPET PRESENTATION ADDITION EXISTING PRESENTATION 12' - 0"12' - 0" CARWASH 17'-4" T.O. PARAPET. 16'-0" J.B.E. 16'-0" J.B.E. 15'-4" J.B.E. 15'-4" J.B.E. 17'-4" T.O. PARAPET 17'-4" T.O. PARAPET. 17'-4" T.O. PARAPET RD SRD RD SRD THE AUTO SUPERSTORE IN ASSOCIATION WITH PIEPER O'BRIEN HERR ARCHITECTS A 2.1PALM DESERT - SALES EXPANSION STORE NO. 6113 - 73-450 DINAH SHORE DRIVE- PALM DESERT, CA 92211 CONCEPTUAL ROOF PLANS20-22031.00 07 DEC 2022 CARMAX THE AUTO SUPERSTORE WEST COAST, INC. 12800 TUCKAHOE CREEK PKWY. RICHMOND, VA 23238 (804) 747-0422 ROOF PLAN - SALES EXPANSION ROOF PLAN - CARWASH T IM E R VALVE ROOM EX122 TOILET EX123 FQC EX124 WET BAY EX121 TOOL AREA EX120 SERVICE EX119 OPERATIONAL SUPPORT EX102 SALES AREA EX100 PARTS EX107 CASH EX106 CHAT ROOM EX105 FILE CLOSET EX115 DATA/ PBX EX114 CONFERENCE EX116 CORR. EX108JANITOREX113ELEC. EX112 CORR. EX109 WOMEN EX110 MEN EX111 WAITING EX101 PRESENTATION EX118 WORK CENTER EX103 PARTS RECEIVING EX117 BREAK 132 CORRIDOR 133 IDF 135 WOMEN 137 MEN 134 2' - 0"EQ 4' - 8"9' - 4"4' - 8"EQ 58' - 1 3/8"EXISTING30' - 3 5/8"ADDITION27' - 9 3/4"EXISTING 51' - 5 7/8" ADDITION 80' - 1 3/4"EXISTING43' - 3"EXISTING22' - 8 1/2"EXISTING20' - 2 1/2"EXISTING/ADDITION 28' - 0" EXISTING 51' - 3" EXISTING 80' - 10 3/4" SALES ADDITION 104EXISTING27' - 4 3/4"C/E VESTIBULE 125 12' - 0"9' - 7"4' - 8"9' - 4"4' - 8"ADDITION20' - 0"CARWASH 139 52' - 0"18' - 0"THE AUTO SUPERSTORE IN ASSOCIATION WITH PIEPER O'BRIEN HERR ARCHITECTS A 2.0PALM DESERT - SALES EXPANSION STORE NO. 6113 - 73-450 DINAH SHORE DRIVE- PALM DESERT, CA 92211 CONCEPTUAL FLOOR PLANS20-22031.00 07 DEC 2022 CARMAX THE AUTO SUPERSTORE WEST COAST, INC. 12800 TUCKAHOE CREEK PKWY. RICHMOND, VA 23238 (804) 747-0422 FLOOR PLAN - SALES EXPANSION FLOOR PLAN - CARWASH LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 1/9 Rev. 09/08/21 SPEC.1045.A.0620 Catalog #:Project: Date:Type:Prepared By: Mirada Medium (MRM) Outdoor LED Area Light FEATURES & SPECIFICATIONS Construction • Rugged die-cast aluminum housing contains factory prewired driver and optical unit. Cast aluminum wiring access door located underneath. • Designed to mount to square or round poles. • Fixtures are finished with LSI’s DuraGrip® polyester powder coat finishing process. The DuraGrip finish withstands extreme weather changes without cracking or peeling. Other standard LSI finishes available. Consult factory. • Shipping weight: 37 lbs in carton. Optical System • State-of-the-Art one piece silicone optic sheet delivers industry leading optical control with an integrated gasket to provide IP66 rated sealed optical chamber in 1 component. • Proprietary silicone refractor optics provide exceptional coverage and uniformity in IES Types 2, 3, 5W, FT, FTA and AM. • Silicone optical material does not yellow or crack with age and provides a typical light transmittance of 93%. • Zero uplight. • Available in 5000K, 4000K, and 3000K color temperatures per ANSI C78.377. Also Available in Phosphor Converted Amber with Peak intensity at 610nm. • Minimum CRI of 70. • Integral louver (IL) and house-side shield (IH) options available for improved backlight control without sacrificing street side performance. See page 3 for more details. Electrical • High-performance programmable driver features over-voltage, under-voltage, short- circuit and over temperature protection. Custom lumen and wattage packages available. • 0-10V dimming (10% - 100%) standard. • Standard Universal Voltage (120-277 Vac) Input 50/60 Hz or optional High Voltage (347-480 Vac). • L80 Calculated Life: >100k Hours (See Lumen Maintenance on Page 5) • Total harmonic distortion: <20% • Operating temperature: -40°C to +50°C (-40°F to +122°F). 42L and 48L lumen packages rated to +40ºC. • Power factor: >.90 • Input power stays constant over life. • Field replaceable 10kV surge protection device meets a minimum Category C Low operation (per ANSI/IEEE C62.41.2). • High-efficacy LEDs mounted to metal-core circuit board to maximize heat dissipation • Components are fully encased in potting material for moisture resistance. Driver complies with FCC standards. Driver and key electronic components can easily be accessed. Controls • Optional integral passive infrared Bluetooth™ motion and photocell sensor (see page 9 for more details). Fixtures operate independently and can be commissioned via iOS or Android configuration app • LSI’s AirLink™ wireless control system options reduce energy and maintenance costs while optimizing light quality 24/7. (see page 9 for more details). Installation • Designed to mount to square or round poles. • A single fastener secures the hinged door, underneath the housing and provides quick & easy access to the electrical compartment. • Included terminal block accepts up to 12 ga. wire. • Utilizes LSI’s traditional 3” drill pattern B3 for easy fastening of LSI products. (See drawing on page 9) Warranty • LSI LED Fixtures carry a 5-year warranty. Listings • Listed to UL 1598 and UL 8750. • Meets Buy American Act requirements. • IDA compliant; with 3000K color temperature selection. • Title 24 Compliant; see local ordinance for qualification information. • Suitable for wet Locations. • IP66 rated Luminaire per IEC 60598. • 3G rated for ANSI C136.31 high vibration applications are qualified. • DesignLights Consortium® (DLC) qualified product. Not all versions of this product may be DLC qualified. Please check the DLC Qualified Products List at www.designlights. org/QPL to confirm which versions are qualified. • Patented Silicone Optics (US Patent NO. 10,816,165 B2) • IK08 rated luminiare per IEC 66262 mechanical impact code Specifications and dimensions subject to change without notice. OVERVIEW Lumen Package 7,000 - 48,000 Wattage Range 48 - 401 Efficacy Range (LPW)117 - 160 Weight lbs(kg)30 (13.6) QUICK LINKS Ordering Guide Performance Photometrics Dimensions IP66 IK08 LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 2/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light ORDERING GUIDE Back to Quick Links LuminairePrefix Light Source Lumen Package LightOutput Distribution Orientation2 Voltage Driver MRM - Mirada LED 7L - 7,000 lms 9L - 9,000 lms 12L - 12,000 lms 18L - 18,000 lms 24L - 24,000 lms 30L - 30,000 lms 36L - 36,000 lms 42L - 42,000 lms 48L - 48,000 lms Custom Lumen Packages1 SIL - Silicone 2 - Type 2 3 - Type 3 5W - Type 5 Wide FT - Forward Throw FTA - Forward Throw Automotive AM - Automotive Merchandise (blank) - standard L- Optics rotated left 90° R - Optics rotated right 90° UNV - Universal Voltage (120-277V) HV - High Voltage (347-480V) DIM - 0-10V Dimming (0-10%) TYPICAL ORDER EXAMPLE: MRM LED 36L SIL FTA UNV DIM 50 70CRI ALSCS04 BRZ IL Color Temp Color Rendering Finish Options 50 - 5,000 CCT 40 - 4,000 CCT 30 - 3,000 CCT AMB - Phosphor Converted Amber12 70CRI - 70 CRI BLK - Black BRZ - Dark Bronze GMG - Gun Metal Gray GPT - Graphite MSV - Metallic Silver PLP - Platinum Plus SVG - Satin Verde Green WHT - White (Blank) - None IH - Integral Houseside Shield2 IL - Integral Louver (Sharp Spill Light Cutoff)2 Controls (Choose One) (Blank) - None Wireless Controls System ALSC - AirLink Synapse Control System ALSCH - AirLink Synapse Control System Host / Satelite 3 ALSCS02 - AirLink Synapse Control System with 12-20’ Motion Sensor ALSCHS02 - AirLink Synapse Control System Host / Satelite with 12-20’ Motion Sensor 3 ALSCS04 - AirLink Synapse Control System with 20-40’ Motion Sensor ALSCHS04 - AirLink Synapse Control System Host / Satelite with 20-40’ Motion Sensor 3 ALBCS1 - AirLink Blue Wireless Motion & Photo Sensor Controller (8-24’ mounting height) ALBCS2 - AirLink Blue Wireless Motion & Photo Sensor Controller (25-40’ mounting height) Stand-Alone Controls EXT - 0-10v Dimming leads extended to housing exterior CR7P - 7 Pin Control Receptacle ANSI C136.41 6 IMSBT1- Integral Bluetooth™ Motion and Photocell Sensor (8-24’ MH)5 IMSBT2- Integral Bluetooth™ Motion and Photocell Sensor (25-40’ MH)5 Button Type Photocells PCI120 - 120V PCI208-277 - 208 -277V PCI347 - 347V Lutron Limelight Controls LLC – LimeLight Integral Wireless Radio Control by Lutron4 LLCS1 – Limelight Integral Wireless Radio Control and PIR Motion/ Daylight Sensor by Lutron 8-15’ mt height4 LLCS2 – Limelight Integral Wireless Radio Control and PIR Motion/ Daylight Sensor by Lutron 16-30’ mt height4 LLCS3 – Limelight Integral Wireless Radio Control and PIR Motion/ Daylight Sensor by Lutron 31-40’ mt height4 Accessory Ordering Information7 FOOTNOTES: 1. Custom lumen and wattage packages available, consult factory. Values are within industry standard tolerances but not DLC listed. 2. Not available with 5W distribution 3. Consult Factory for availability. 4. Not available in HV. 5. IMSBT is field configurable via the LSI app that can be downloaded from your smartphone’s native app store. 6. Control device or shorting cap must be ordered separately. See Accessory Ordering Information. 7. Accessories are shipped separately and field installed. 8. Factory installed CR7P option required. See Options. 9. “CLR” denotes finish. See Finish options. 10. Only available with ALSC/ALSCH control options. 11. Fusing must be located in hand hole of pole. See Fusing Accessory Guide for compatability. 12. Only available in 9L and 12L Lumen Packages. Consult factory for lead time and availability. Mounting Accessories9 Description Order Number10 Universal Mounting Bracket 684616CLR Adjustable Slip Fitter (2" - 2 3/8" Tenon)688138CLR Horizontal Slip Fitter (2" - 2 3/8" Tenon)652761CLR Quick Mount Pole Bracket (Square Pole)687073CLR Quick Mount Pole Bracket (4-5" Round Pole)689903CLR 15 Tilt Quick Mount Pole Bracket (Square Pole)688003CLR 15 Tilt Quick Mount Pole Bracket (4-5" Round Pole)689905CLR Wall Mount Bracket 382132CLR Wood Pole Bracket (6” Minimum Pole Diameter)751219CLR Controls Accessories Description Order Numberr10 PC120 Photocell for use with CR7P option (120V)8 122514 PC208-277 Photocell for use with CR7P option (208V, 240V, 277V)8 122515 Twist Lock Photocell (347V) for use with CR7P 8 122516 Twist Lock Photocell (480V) for use with CR7P 8 1225180 AirLink 5 Pin Twist Lock Controller 8 661409 AirLink 7 Pin Twist Lock Controller 8 661410 PMOS24-24V Pole-Mounted Occupancy Sensor (24V)663284CLR Shorting Cap for use with CR7P 149328 Fusing Options11 Description Order Number Single Fusing (120V) See Fusing Accessory Guide Single Fusing (277V) Double Fusing (208V, 240V) Double Fusing (480V) Double Fusing (347V) Miscellaneous Accessories Description Order Number Integral Louver/Shield 690981 Integral House Side Shield 743415 10’ Linear Bird Spike Kit (3’ Recommended per Luminaire)751632 LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 3/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light Optics Rotated Left Straight Optics Rotated Right Use Type R (Optics Rotated Right) Pole EXAMPLE Use Type L (Optics Rotated Left) OPTICS ROTATION ACCESSORIES/OPTIONS Integral Louver (IL) and House-Side Shield (IH) Accessory louver and shield available for improved backlight control without sacrificing street side performance. LSI’s Integral Louver (L) and Integral House-Side Shield (IH) options deliver backlight control that significantly reduces spill light behind the poles for applications with pole locations close to adjacent properties. The design maximizes forward reflected light while reducing glare, maintaining the optical distribution selected, and most importantly eliminating light trespass. Both options rotate with the optical distribution. 7 Pin Photoelectric Control 7-pin ANSI C136.41-2013 control receptacle option available for twist lock photocontrols or wireless control modules. Control accessories sold separately. Dimming leads from the receptacle will be connected to the driver dimming leads (Consult factory for alternate wiring). Luminaire Shown with PCR 7P Luminaire Shown with IMSBT & IL/IH Options Top View IMSBT IH/IL LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 4/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light PERFORMANCE Back to Quick Links Delivered Lumens* Lumen Package Distribution CRI 3000K CCT 4000K CCT 5000K CCT WattageDelivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating 7L 2 70 7560 157 B2-U0-G2 7560 157 B2-U0-G2 7560 157 B2-U0-G2 48 3 7616 159 B1-U0-G2 7616 159 B1-U0-G2 7616 159 B1-U0-G2 5W 7292 152 B3-U0-G1 7292 152 B3-U0-G1 7292 152 B3-U0-G1 FT 7562 158 B2-U0-G2 7562 158 B2-U0-G2 7562 158 B2-U0-G2 FTA 7595 158 B2-U0-G2 7595 158 B2-U0-G2 7595 158 B2-U0-G2 AM 7687 160 B1-U0-G1 7687 160 B1-U0-G1 7687 160 B1-U0-G1 9L 2 70 9853 159 B2-U0-G2 9853 159 B2-U0-G2 9853 159 B2-U0-G2 62 3 9926 160 B2-U0-G2 9926 160 B2-U0-G2 9926 160 B2-U0-G2 5W 9504 153 B3-U0-G2 9504 153 B3-U0-G2 9504 153 B3-U0-G2 FT 9856 159 B2-U0-G3 9856 159 B2-U0-G3 9856 159 B2-U0-G3 FTA 9900 160 B2-U0-G2 9900 160 B2-U0-G2 9900 160 B2-U0-G2 AM 10019 162 B2-U0-G1 10019 162 B2-U0-G1 10019 162 B2-U0-G1 12L 2 70 13135 155 B3-U0-G2 13135 155 B3-U0-G2 13135 155 B3-U0-G2 85 3 13232 156 B2-U0-G2 13232 156 B2-U0-G2 13232 156 B2-U0-G2 5W 12669 149 B4-U0-G2 12669 149 B4-U0-G2 12669 149 B4-U0-G2 FT 13138 155 B2-U0-G3 13138 155 B2-U0-G3 13138 155 B2-U0-G3 FTA 13196 155 B2-U0-G2 13196 155 B2-U0-G2 13196 155 B2-U0-G2 AM 13355 157 B2-U0-G2 13355 157 B2-U0-G2 13355 157 B2-U0-G2 18L 2 70 19318 143 B3-U0-G3 19318 143 B3-U0-G3 19318 143 B3-U0-G3 135 3 19461 144 B3-U0-G3 19461 144 B3-U0-G3 19461 144 B3-U0-G3 5W 18633 138 B4-U0-G2 18633 138 B4-U0-G2 18633 138 B4-U0-G2 FT 19324 143 B3-U0-G3 19324 143 B3-U0-G3 19324 143 B3-U0-G3 FTA 19408 144 B3-U0-G3 19408 144 B3-U0-G3 19408 144 B3-U0-G3 AM 19641 145 B3-U0-G2 19641 145 B3-U0-G2 19641 145 B3-U0-G2 24L 2 70 25957 147 B4-U0-G3 25957 147 B4-U0-G3 25957 147 B4-U0-G3 176 3 26149 149 B3-U0-G4 26149 149 B3-U0-G4 26149 149 B3-U0-G4 5W 25037 142 B5-U0-G3 25037 142 B5-U0-G3 25037 142 B5-U0-G3 FT 25964 148 B3-U0-G4 25964 148 B3-U0-G4 25964 148 B3-U0-G4 FTA 26077 148 B3-U0-G3 26077 148 B3-U0-G3 26077 148 B3-U0-G3 AM 26393 150 B3-U0-G2 26393 150 B3-U0-G2 26393 150 B3-U0-G2 30L 2 70 32417 140 B4-U0-G3 32417 140 B4-U0-G3 32417 140 B4-U0-G3 232 3 32656 141 B3-U0-G4 32656 141 B3-U0-G4 32656 141 B3-U0-G4 5W 31267 135 B5-U0-G3 31267 135 B5-U0-G3 31267 135 B5-U0-G3 FT 32424 140 B3-U0-G4 32424 140 B3-U0-G4 32424 140 B3-U0-G4 FTA 32566 140 B4-U0-G3 32566 140 B4-U0-G3 32566 140 B4-U0-G3 AM 32960 142 B3-U0-G3 32960 142 B3-U0-G3 32960 142 B3-U0-G3 36L 2 70 38275 133 B4-U0-G4 38275 133 B4-U0-G4 38275 133 B4-U0-G4 288 3 38557 134 B4-U0-G5 38557 134 B4-U0-G5 38557 134 B4-U0-G5 5W 36917 128 B5-U0-G4 36917 128 B5-U0-G4 36917 128 B5-U0-G4 FT 38283 133 B4-U0-G5 38283 133 B4-U0-G5 38283 133 B4-U0-G5 FTA 38450 134 B4-U0-G4 38450 134 B4-U0-G4 38450 134 B4-U0-G4 AM 38916 135 B3-U0-G3 38916 135 B3-U0-G3 38916 135 B3-U0-G3 LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 5/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light PERFORMANCE (CONT.) ELECTRICAL DATA (AMPS)* Lumens 120V 208V 240V 277V 347V 480V 7L 0.40 0.23 0.20 0.17 0.14 0.10 9L 0.52 0.30 0.26 0.22 0.18 0.13 12L 0.71 0.41 0.35 0.31 0.24 0.18 18L 1.13 0.65 0.56 0.49 0.39 0.28 24L 1.47 0.85 0.73 0.64 0.51 0.37 30L 1.93 1.12 0.97 0.84 0.67 0.48 36L 2.40 1.38 1.20 1.04 0.83 0.60 42L 2.95 1.70 1.48 1.28 1.02 0.74 48L 3.4A 1.9A 1.7A 1.5A 1.2A 0.8A ELECTRICAL DATA - PHOSPHOR CONVERTED AMBER (AMPS)* Lumens Watts 120V 208V 240V 277V 347V 480V 9L 74.3 0.6A 0.4A 0.3A 0.3A 0.2A 0.2A 12L 102.9 0.9A 0.5A 0.4A 0.4A 0.3A 0.2A RECOMMENDED LUMEN MAINTENANCE1 (7-18L) Ambient Intial2 25h2 50hr2 75hr2 100hr2 0-50 C 100%96%92%88%84% RECOMMENDED LUMEN MAINTENANCE1 (24-48L) Ambient Intial2 25h2 50hr2 75hr2 100hr2 0-40 C 100%100%97%94%92% DELIVERED LUMENS* Lumen Package Distribution Phosphor Converted Amber (Peak 610mm) WattageDelivered Lumens Efficacy BUG Rating 9L 2 5848 80 B2-U0-G2 74 2 - IL 3644 50 B0-U0-G1 3 6018 82 B1-U0-G2 3 - IL 4468 61 B0-U0-G2 5W 5471 74 B3-U0-G1 FT 5801 79 B1-U0-G2 FT - IL 3649 50 B0-U0-G1 FTA 5924 81 B1-U0-G1 FTA - IL 4243 58 B1-U0-G1 12L 2 7530 74 B2-U0-G2 102 2 - IL 4692 46 B0-U0-G1 3 7749 76 B1-U0-G2 3 - IL 5753 57 B0-U0-G2 5W 7045 69 B3-U0-G2 FT 7470 73 B2-U0-G2 FT - IL 4699 46 B0-UO-G2 FTA 7628 75 B2-U0-G2 FTA-IL 5464 54 B1-U0-G1 1. Lumen maintenance values at 25C are calculated per TM-21 based on LM-80 data and in-situ testing. 2. In accordance with IESNA TM-21-11, Projected Values represent interpolated value based on time durations that are within six times the IESNA LM-80-08 total test duration for the device under testing. 3. In accordance with IESNA TM-21-11, Calculated Values represent time durations that exceed six times the IESNA LM-80-08 total test duration for the device under testing. *Electrical data at 25°C (77°F). Actual wattage may differ by +/-10% *LEDs are frequently updated therefore values are nominal. Delivered Lumens* Lumen Package Distribution CRI 3000K CCT 4000K CCT 5000K CCT WattageDelivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating 42L 2 70 44118 125 B5-U0-G4 44118 125 B5-U0-G4 44118 125 B5-U0-G4 354 3 44444 126 B4-U0-G5 44444 126 B4-U0-G5 44444 126 B4-U0-G5 5W 42555 120 B5-U0-G4 42555 120 B5-U0-G4 42555 120 B5-U0-G4 FT 44130 125 B4-U0-G5 44130 125 B4-U0-G5 44130 125 B4-U0-G5 FTA 44322 125 B4-U0-G4 44322 125 B4-U0-G4 44322 125 B4-U0-G4 AM 44859 127 B4-U0-G3 44859 127 B4-U0-G3 44859 127 B4-U0-G3 48L 2 70 48795 122 B5-U0-G4 48795 122 B5-U0-G4 48795 122 B5-U0-G4 401 3 49156 123 B4-U0-G5 49156 123 B4-U0-G5 49156 123 B4-U0-G5 5W 47066 117 B5-U0-G4 47066 117 B5-U0-G4 47066 117 B5-U0-G4 FT 48809 122 B4-U0-G5 48809 122 B4-U0-G5 48809 122 B4-U0-G5 FTA 49021 122 B5-U0-G4 49021 122 B5-U0-G4 49021 122 B5-U0-G4 AM 49615 124 B4-U0-G3 49615 124 B4-U0-G3 49615 124 B4-U0-G3 LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 6/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light Back to Quick Links Luminaire photometry has been conducted by a NVLAP accredited testing laboratory in accordance with IESNA LM-79-08. As specified by IESNA LM-79-08 the entire luminaire is tested as the source resulting in a luminaire efficiency of 100%. See https://www.lsicorp.com/product/mirada-medium/ for detailed photometric data. LUMINAIRE DATA Type 2 Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 32,416 Watts 232 Efficacy 140 IES Type Type II - Short BUG Rating B4-U0-G3 LUMINAIRE DATA Type 3 Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 32,656 Watts 232 Efficacy 141 IES Type Type III - Short BUG Rating B3-U0-G4 Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°4796 15% Medium (30-60)°19811 61% High (60-80)°7474 23% Very High (80-90)°335 1% Uplight (90-180)°0 0% Total Flux 32416 100% Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°3385 10% Medium (30-60)°16250 50% High (60-80)°12430 38% Very High (80-90)°591 2% Uplight (90-180)°0 0% Total Flux 32656 100% MRM-LED-30L-SIL-2-40-70CRI MRM-LED-30L-SIL-3-40-70CRI ISO FOOTCANDLE ISO FOOTCANDLE POLAR CURVE POLAR CURVE .5 1 2 5 6310 12620 18929 25239 1 2 25’ Mounting Height/ 25’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC PHOTOMETRICS .5 1 2 5 2 5470 10941 16411 21881 1 25’ Mounting Height/ 25’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC LUMINAIRE DATA Type FT Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 32,424 Watts 232 Efficacy 140 IES Type Type IV - Short BUG Rating B3-U0-G4 Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°3952 12% Medium (30-60)°15505 48% High (60-80)°12279 38% Very High (80-90)°688 2% Uplight (90-180)°0 0% Total Flux 32424 100% MRM-LED-30L-SIL-FT-40-70CRI ISO FOOTCANDLE POLAR CURVE .5 1 2 5 4752 9503 14255 19006 1 2 20’ Mounting Height/15’ Grid Spacing 20 FC 10 FC 5 FC 2 FC LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 7/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light PHOTOMETRICS (CONT) LUMINAIRE DATA Type FTA Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 32,566 Watts 232 Efficacy 140 IES Type Type VS - Short BUG Rating B4-U0-G3 LUMINAIRE DATA Type AM Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 32,960 Watts 232 Efficacy 142 IES Type Type III - Very Short BUG Rating B3-U0-G3 LUMINAIRE DATA Type 5W Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 31,267 Watts 232 Efficacy 135 IES Type Type VS - Short BUG Rating B5-U0-G3 Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°6986 21% Medium (30-60)°19172 59% High (60-80)°5875 18% Very High (80-90)°534 2% Uplight (90-180)°0 0% Total Flux 32566 100% Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°6363 9% Medium (30-60)°22026 43% High (60-80)°4192 48% Very High (80-90)°379 1% Uplight (90-180)°0 0% Total Flux 32960 100% Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°3138 10% Medium (30-60)°13193 42% High (60-80)°14641 47% Very High (80-90)°296 1% Uplight (90-180)°0 0% Total Flux 31267 100% MRM-LED-30L-SIL-FTA-40-70CRI MRM-LED-30L-SIL-AM-40-70CRI MRM-LED-30L-SIL-5W-40-70CRI ISO FOOTCANDLE ISO FOOTCANDLE ISO FOOTCANDLE POLAR CURVE POLAR CURVE POLAR CURVE .5 1 2 5 4127 8253 12380 16506 1 2 25’ Mounting Height/ 25’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC .51 2 5 26544 6636 13272 19908 1 2 25’ Mounting Height/ 25’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC .5 1 2 5 1 3777 7554 11330 15107 2 25’ Mounting Height/ 25’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 8/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light PRODUCT DIMENSIONS Back to Quick Links CONTROLS AirLink Wireless Lighting Controller The AirLink integrated controller is a California Title 24 compliant lighting controller that provides real-time light monitoring and control with utility-grade power monitoring. It includes a 24V sensor input and power supply to connect a sensor into the outdoor AirLink wireless lighting system. The wireless integrated controller is compatible with this fixture. Click the link below to learn more details about AirLink. https://www.lsicorp.com/wp-content/uploads/documents/products/airlink-outdoor-specsheet.pdf Integral Bluetooth™ Motion and Photocell Sensor (IMSBT) Slim low profile sensor provides multi-level control based on motion and/or daylight. Sensor controls 0-10 VDC LED drivers and is rated for cold and wet locations (-30° C to 70° C). Two unique PIR lenses are available and used based on fixture mounting height. All control parameters are adjustable via an iOS or Android App capable of storing and transmitting sensor profiles. Click the link below to learn more details about IMSBT. https://www.lsicorp.com/wp-content/uploads/documents/products/imsbt-specsheet.pdf AirLink Blue Wireless Bluetooth Mesh Outdoor Lighting Control System that provides energy savings, code compliance and enhanced safety/security for parking lots and parking garages. Three key components; Bluetooth wireless radio/sensor controller, Time Keeper and an iOS App. Capable of grouping multiple fixtures and sensors as well as scheduling time-based events by zone. Radio/Sensor Controller is factory integrated into Area/Site, Wall Mounted, Parking Garage and Canopy luminaires. Click the link below to learn more details about AirLink Blue. https://www.lsicorp.com/product/airlink-blue/ 7.6"(192mm) 13-1/2"(342mm) 7.8"(198mm)6.5"(165mm) 31.3"(795mm) IMSBT Motion & Photocell Sensor Bottom View Top View Photo Control Receptacle B3 Pole Drill Pattern ø0.875 ø0.563 2.422 1.211 LUMINAIRE EPA CHART - MRM Single D180° D90° 0.5 1.0 0.8 1.5 1.5 1.9 1.9 1.9 2.3 1.0 1.0 1.0 2.5 3.3 2.5 2.8 3.9 2.8 T90° TN120° Q90° 0º30º45ºTilt Degree 0º30º45ºTilt Degree LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (513) 372-3200 • ©2020 LSI Industries Inc. All Rights Reserved. Specifications subject to change without notice. Page 9/9 Rev. 09/08/21 SPEC.1045.A.0620 Type: Mirada Medium Outdoor LED Area Light POLES & BRACKETS LSI offers a full line of poles and mounting accessories to complete your lighting assembly. Aluminum and steel in both square and round shafts. In addition, LSI offers round tapered, fluted and hinge based poles. Designed and engineered for durability and protected with our oven baked DuraGrip Protection System. Also available with our DuraGrip+ Protection system for unmatched corrosion resistance and an extended warranty. American made in our Ohio facility with industry leading lead times. Click the link below to learn more details about poles & brackets. https://www.lsicorp.com/products/poles-brackets/ Square Pole 14'-39' Round Pole 10'-30' Tapered Pole 20'-39' BKA UMB CLR The 3G rated UMB allows for seamless integration of LSI luminaires onto existing/ retrofit or new construction poles. The UMB was designed for square or round (tapered or straight) poles with two mounting hole spacings between 3.5” – 5”. BKA ASF CLR The adjustable Slip Fitter is a 3G rated rugged die cast aluminum adapter to mount LSI luminaires onto a onto a 2” iron pipe , 2 3/8 OD tenon. The Adjustable Slip Fitter can be rotated 180° allowing for tilting LSI luminaires up to 45° and 90° when using a vertical tenon. BKS PQMH CLR The Pole Quick Mount Bracket allows for lightning fast installation of LSI luminaires onto existing and new construction poles with LSI’s B3 or B5 standard pole bolt patterns. BKS PQM15 CLR The Pole Quick Mount Bracket allows for preset 15° uptilt of LSI luminaires for greater throw of light and increased vertical illumination as well as fast installation onto poles with LSI’s 3” or 5” bolt pattern. BKA UMB CLR BKA ASF CLR BKS PQMH CLR BKS PQM15 CLR Square Pole 14'-39' Round Pole 10'-30' Tapered Pole 20'-39' LSI oers a full line of poles and mounting accessories to complete your lighting assembly. Aluminum and steel in both square and round shafts. In addition, LSI oers round tapered, fluted and hinge based poles. Designed and engineered for durability and protected with our oven baked DuraGrip Protection System. Also available with our DuraGrip+ Protection system for unmatched corrosion resistance and an extended warranty. American made in our Ohio facility with industry leading lead times. The adjustable Slip Fitter is a 3G rated rugged die cast aluminum adapter to mount LSI luminaires onto a onto a 2” iron pipe , 2 3/8 OD tenon. The Adjustable Slip Fitter can be rotated 180° allowing for tilting LSI luminaires up to 45° and 90° when using a vertical tenon. The 3G rated UMB allows for seamless integration of LSI luminaires onto existing/ retrofit or new construction poles. The UMB was designed for square or round (tapered or straight) poles with two mounting hole spacings between 3.5” – 5”. The Pole Quick Mount Bracket allows for preset 15° uptilt of LSI luminaires for greater throw of light and increased vertical illumination as well as fast installation onto poles with LSI's 3" or 5" bolt pattern. The Pole Quick Mount Bracket allows for lightning fast installation of LSI luminaires onto existing and new construction poles with LSI's B3 or B5 standard pole bolt patterns. Page 1/5 Rev. 10/06/22 SPEC.1024.A.0420 Catalog #:Project: Date:Type:Prepared By: LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (800) 436-7800 • ©LSI Industries Inc. All Rights Reserved. Specifi cations subject to change without notice. Mirada Medium Wall Sconce (XWM) Outdoor Wall Sconce FEATURES & SPECIFICATIONS Construction • Rugged die-cast aluminum housing contains factory prewired driver and optical unit. Hinged die-cast aluminum wiring access door located underneath. • Galvanized-steel universal wall mount bracket comes standard with hinging mechanism to easily access the junction box wire connections without removing the luminaire. • Optional pole-mounting bracket (XPMA) permits mounting to standard poles. • Fixtures are finished with LSI’s DuraGrip® polyester powder coat finishing process. The DuraGrip finish withstands extreme weather changes without cracking or peeling. Other standard LSI finishes available. Consult factory. • Shipping weight: 30 lbs in carton. Optical System • State-of-the-Art one piece silicone optic sheet delivers industry leading optical control with an integrated gasket to provide IP65 rated sealed optical chamber in 1 component. • Proprietary silicone refractor optics provide exceptional coverage and uniformity in Types 2, 3, and Forward Throw (FT) distributions. • Silicone optical material does not yellow or crack with age and provides a typical light transmittance of 93%. • Zero uplight. • Available in 5000K, 4000K and 3000K color temperatures per ANSI C78.377. Also Available in Phosphor Converted Amber with Peak intensity at 610nm. • Minimum CRI of 70. Electrical • High-performance programmable driver features over-voltage, under-voltage, short- circuit and over temperature protection. Custom lumen and wattage packages available. • 0-10V dimming (10% - 100%) standard. • Standard Universal Voltage (120-277 Vac) Input 50/60 Hz or optional High Voltage (347-480 Vac). • L80 Calculated Life: >100k Hours • Total harmonic distortion: <20% • 3L to 12L operating temperature: -40°C to +50°C (-40°F to +122°F) • 15L operating temperature: -40°C to +45°C (-40°F to +113°F). • 18L operating temperature: -40°C to +40°C (-40°F to +104°F). • 21L operating temperature: -40°C to +35°C (-40°F to + 95°F). • Power factor: >.90 • Input power stays constant over life. • Optional 10kV surge protection device meets a minimum Category C Low operation (per ANSI/IEEE C62.41.2). • High-efficacy LEDs mounted to metal-core circuit board to maximize heat dissipation • Components are fully encased in potting material for moisture resistance. Driver complies with FCC standards. Driver and key electronic components can easily be accessed via hinged door. • Optional integral emergency battery pack provides 90-minutes of constant power to the LED system, ensuring code compliance. A test switch/indicator button is installed on the housing for ease of maintenance. The fixture delivers 1500 lumens during emergency mode. Controls • Integral passive infrared Bluetooth™ motion and photocell sensor options. Fixtures operate independently and can be commissioned via an iOS or Android configuration app. Updates and modifications to the control strategy are easily implemented via an intuitive app. • LSI’s AirLink™ Blue lighting control system is a simple feature rich wireless Bluetooth mesh network. The integrated fixture sensor module provides wireless control of grouped fixtures based on motion sensors, daylight or a fully customizable schedule. Installation • Universal wall mounting plate easily mounts directly to 4” octagonal or square junction box. • 2 fasteners secure the hinged door underneath the housing and provide quick & easy access to the electrical compartment for installing/servicing. • Optional terminal block accepts up to 12 ga wire. Warranty • LSI LED Fixtures carry a 5-year warranty. • 1 Year warranty on Battery Back-up option. Listings • Listed to UL 1598 and UL 8750. • Meets Buy American Act requirements. • IDA compliant; with 3000K or lower color temperature selection. • Title 24 Compliant; see local ordinance for qualification information. • Suitable for wet Locations. • IP65 rated luminaire per IEC 60598. • 3G rated for ANSI C136.31 high vibration applications when pole mounted (using optional XPMA bracket) or wall mounted. • IK08 rated luminiare per IEC 66262 mechanical impact code • DesignLights Consortium® (DLC) qualified product. Not all versions of this product may be DLC qualified. Please check the DLC Qualified Products List at www.designlights. org/QPL to confirm which versions are qualified. OVERVIEW Lumen Range 3,000 - 21,000 Wattage Range 23 - 175 Efficacy Range (LPW)125 - 158 Weight lbs(kg)30 (13.6) QUICK LINKS Ordering Guide Performance Photometrics Dimensions Page 2/5 Rev. 10/06/22 SPEC.1024.A.0420 Type: Mirada Wall Sconce (XWM) LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (800) 436-7800 • ©LSI Industries Inc. All Rights Reserved. Specifi cations subject to change without notice. ORDERING GUIDE Back to Quick Links Family Distribution LED Technology Lumen Package Color Temperature Voltage XWM - Mirada Medium Wall Sconce 2 - Type 2 3 - Type 3 FT - Type 4 Forward Throw LED 3L - 3,000 lms 4L - 4,000 lms 6L - 6,000 lms 8L - 8,000 lms 12L - 12,000 lms 15L - 15,000 lms 18L - 18,000 lms 21L - 21,000 lms Custom Lumen Packages6 30 - 3000K 40 - 4000K 50 - 5000K AMB - Phosphor Converted Amber1 UE - Universal Voltage (120-277V) HV - High Voltage (347-480V) Finish Controls (Choose One)Options BLK - Black BRZ - Dark Bronze GMG - Gun Metal Gray GPT - Graphite MSV - Metallic Silver PLP - Platinum Plus SVG - Satin Verde Green WHT - White Wireless Controls ALSC - Airlink Synapse Control System ALSCS01 - AirLink Synapse Control System with 8-12’ Motion Sensor ALSCS02 - AirLink Synapse Control System with 12-20’ Motion Sensor ALBCS1 - AirLink Blue Wireless Motion & Photo Sensor Controller (8-24’ mounting height) ALBCS2 - AirLink Blue Wireless Motion & Photo Sensor Controller (25-40’ mounting height) Standalone Controls DIM - 0-10v Dimming leads extended to housing exterior IMSBT1- Integral Bluetooth™ Motion and Photocell Sensor max 8-24’ mounting height 4 IMSBT2- Integral Bluetooth Motion and Photocell Sensor max 25-40’ mounting height 4 Button Type Photocells PCI120 - 120V PCI208-277 - 208 -277V PCI347 - 347V BB - Battery Back-up (0°C)2 CWBB - Cold Weather Battery Backup (-20°C)2 XPMA - Pole Mounting Bracket SP1 - 10kV Surge Protection TB - Terminal Block TYPICAL ORDER EXAMPLE: XWM 2 LED 03L 30 UE BRZ ALSC ACCESSORY ORDERING INFORMATION7 1. Only available in 6L Lumen Package. Consult factory for lead time and availability. 2. Not available in HV. 3. Consult Factory for Site Layout. 4. IMSBT is field configurable via the LSI app that can be downloaded from your smartphone’s native app store. 5. Fusing must be located in a hand hole for pole or in the junction box. 6. Custom lumen and wattage packages available consult factory. Values are within industry standard tolerances but not DLC listed. 7. Accessories are shipped separately and field installed. Description Order Number Description Order Number XWM Surface Wiring Box 356915CLR FK347 - Single Fusing FK3475 10’ Linear Bird Spike Kit (2’ Recommended per Luminaire)751632 DFK - Double Fusing DFK2085 FK120 - Single Fusing FK1205 DFK - Double Fusing (240V)DFK2405 FK277 - Single Fusing FK2775 DFK - Double Fusing (480V)DFK4805 Page 3/5 Rev. 10/06/22 SPEC.1024.A.0420 Type: Mirada Wall Sconce (XWM) LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (800) 436-7800 • ©LSI Industries Inc. All Rights Reserved. Specifi cations subject to change without notice. PERFORMANCE Back to Quick Links ELECTRICAL DATA* Lumen Package 120V 208V 240V 277V 347V 480V 03L 0.19 0.11 0.10 0.08 0.07 0.05 04L 0.25 0.15 0.13 0.11 0.09 0.06 06L 0.39 0.23 0.20 0.17 0.14 0.10 08L 0.54 0.31 0.27 0.23 0.19 0.13 12L 0.68 0.39 0.34 0.30 0.24 0.17 15L 0.87 0.50 0.44 0.38 0.30 0.22 18L 1.08 0.63 0.54 0.47 0.37 0.27 21L 1.34 0.77 0.67 0.58 0.46 0.34 RECOMMENDED LUMEN MAINTENANCE (3L-8L)1 Ambient Temperature C Initial 2 25K hrs.2 50K hrs.3 75K hrs.3 100K hrs.3 0 C - 50 C 100%98%95%93%90% RECOMMENDED LUMEN MAINTENANCE (12L-21L)1 Ambient Temperature C Initial 2 25K hrs.2 50K hrs.3 75K hrs.3 100K hrs.3 0 - 35 C 99%97%95%93%91% *Electrical data at 25C (77F). Actual wattage may differ by +/-10%. 1 - Lumen maintenance values at 25C are calculated per TM-21 based on LM-80 data and in-situ testing. 2 - In accordance with IESNA TM-21-11, Projected Values represent interpolated value based on time durations that are within six times the IESNA LM-80-08 total test duration for the device under testing. 3 - Lumen maintenance values at 25C are calculated per TM-21 based on LM-80 data and in-situ testing times the IESNA LM-80-08 total test duration for the device under testing DELIVERED LUMENS* Lumen Package Distribution CRI 3000K 4000K 5000K WattageDelivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating Delivered Lumens Efficacy BUG Rating 03L 2 70 3178 138 B1-U0-G1 3368 146 B1-U0-G1 3313 143 B1-U0-G1 233703224140B1-U0-G1 3416 148 B1-U0-G1 3361 145 B1-U0-G1 FT 70 3160 137 B1-U0-G1 3349 145 B1-U0-G1 3294 143 B1-U0-G1 04L 2 70 4230 139 B1-U0-G1 4483 147 B1-U0-G1 4410 145 B1-U0-G1 303704291141B1-U0-G1 4547 150 B1-U0-G1 4473 147 B1-U0-G1 FT 70 4206 138 B1-U0-G1 4458 147 B1-U0-G1 4385 144 B1-U0-G1 06L 2 70 6326 134 B2-U0-G1 6704 142 B2-U0-G2 6595 140 B2-U0-G2 473706417136B1-U0-G2 6800 144 B1-U0-G2 6689 142 B1-U0-G2 FT 70 6290 134 B2-U0-G2 6666 142 B2-U0-G2 6557 139 B2-U0-G2 08L 2 70 8166 128 B2-U0-G2 8654 135 B2-U0-G2 8513 133 B2-U0-G2 643708283129B2-U0-G2 8778 137 B2-U0-G2 8635 134 B2-U0-G2 FT 70 8120 126 B2-U0-G2 8605 134 B2-U0-G2 8465 132 B2-U0-G2 12L 2 70 11902 146 B3-U0-G2 12358 151 B3-U0-G2 12927 158 B3-U0-G2 8237011834145B2-U0-G2 12287 150 B2-U0-G2 12853 157 B2-U0-G2 FT 70 11737 143 B2-U0-G2 12186 149 B2-U0-G2 12747 156 B2-U0-G2 15L 2 70 14662 140 B3-U0-G3 15223 145 B3-U0-G3 15924 152 B3-U0-G3 10537014603139B2-U0-G2 15162 145 B2-U0-G3 15860 151 B2-U0-G3 FT 70 14502 139 B2-U0-G3 15057 144 B2-U0-G3 15750 150 B2-U0-G3 18L 2 70 17403 134 B3-U0-G3 18069 139 B3-U0-G3 18901 145 B3-U0-G3 13037017438134B3-U0-G3 18106 139 B3-U0-G3 18940 146 B3-U0-G3 FT 70 17259 133 B3-U0-G3 17920 138 B3-U0-G3 18745 144 B3-U0-G3 21L 2 70 20380 127 B3-U0-G3 21160 132 B3-U0-G3 22134 138 B4-U0-G3 16137020375125B3-U0-G3 21155 131 B3-U0-G3 22129 131 B3-U0-G3 FT 70 20215 126 B3-U0-G3 20989 130 B3-U0-G3 21955 136 B3-U0-G3 DELIVERED LUMENS* Lumen Package Distribution Amber WattageDelivered Lumens Efficacy BUG Rating 6L 2 3325 76 B1-U0-G1 43.53338578B1-U0-G1 FT 3343 77 B1-U0-G1 *LEDs are frequently updated therefore values are nominal. Page 4/5 Rev. 10/06/22 SPEC.1024.A.0420 Type: Mirada Wall Sconce (XWM) LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (800) 436-7800 • ©LSI Industries Inc. All Rights Reserved. Specifi cations subject to change without notice. PHOTOMETRICS Back to Quick Links All published luminaire photometric testing performed to IESNA LM-79 standards. ISO footcandle plots below demonstrate the Mirada Wall Sconce (XWM) light patterns only. Not for total fixture output. For complete specifications and IES files, see website. LUMINAIRE DATA Type 2 Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 6,025 Watts 44.7 Efficacy 135 IES Type Type III - Medium BUG Rating B2-U0-G2 LUMINAIRE DATA Type 3 Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 6,133 Watts 44.7 Efficacy 137 IES Type Type III - Medium BUG Rating B1-U0-G2 LUMINAIRE DATA Type FT Distribution Description 4000 Kelvin, 70 CRI Delivered Lumens 6,058 Watts 44.7 Efficacy 136 IES Type Type IV - Short BUG Rating B1-U0-G2 Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°807.1 13.4% Medium (30-60)°3301.0 54.8% High (60-80)°1847.4 30.7% Very High (80-90)°69.2 1.1% Uplight (90-180)°0.0 0.0% Total Flux 6024.7 100% Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°567.4 9.3% Medium (30-60)°3106.3 50.6% High (60-80)°2368.8 38.6% Very High (80-90)°90.7 1.5% Uplight (90-180)°0.0 0.0% Total Flux 6133.2 100% Zonal Lumen Summary Zone Lumens %Luminaire Low (0-30)°779.0 12.9% Medium (30-60)°2584.4 42.7% High (60-80)°2523.2 41.7% Very High (80-90)°170.8 2.8% Uplight (90-180)°0.0 0.0% Total Flux 6057.4 100.0% 3395 4527 2264 1132 1359 4078 5437 2719 2576 3434 1717 859 ISO FOOTCANDLE PLOT ISO FOOTCANDLE PLOT ISO FOOTCANDLE PLOT POLAR CURVE POLAR CURVE POLAR CURVE XWM-2-LED-6L-40 XWM-3-LED-6L-40 XWM-FT-LED-6L-40 15’ Mounting Height / 10’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC 10’ Mounting Height / 10’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC 10’ Mounting Height / 10’ Grid Spacing 5 FC 2 FC 1 FC 0.5 FC Page 5/5 Rev. 10/06/22 SPEC.1024.A.0420 Type: Mirada Wall Sconce (XWM) LSI Industries Inc. 10000 Alliance Rd. Cincinnati, OH 45242 • www.lsicorp.com (800) 436-7800 • ©LSI Industries Inc. All Rights Reserved. Specifi cations subject to change without notice. CONTROLS PRODUCT DIMENSIONS Back to Quick Links 12-3/4" (323mm) 19-15/16" (505mm) 5-5/16" (134mm) 4-1/2" (114mm) 7-1/2" (191mm) AirLink Wireless Lighting Controller The AirLink integrated controller is a California Title 24 compliant lighting controller that provides real-time light monitoring and control with utility-grade power monitoring. It includes a 24V sensor input and power supply to connect a sensor into the outdoor AirLink wireless lighting system. The wireless integrated controller is compatible with this fixture. Click here to learn more about AirLink. Integral Bluetooth™ Motion and Photocell Sensor (IMSBT) Slim low profile sensor provides multi-level control based on motion and/or daylight. Sensor controls 0-10 VDC LED drivers and is rated for cold and wet locations (-30° C to 70° C). Two unique PIR lenses are available and used based on fixture mounting height. All control parameters are adjustable via an iOS or Android App capable of storing and transmitting sensor profiles. Click here to learn more about IMSBT. AirLink Blue Wireless Bluetooth Mesh Outdoor Lighting Control System that provides energy savings, code compliance and enhanced safety/security for parking lots and parking garages. Three key components; Bluetooth wireless radio/sensor controller, Time Keeper and an iOS App. Capable of grouping multiple fixtures and sensors as well as scheduling time-based events by zone. Radio/Sensor Controller is factory integrated into Area/Site, Wall Mounted, Parking Garage and Canopy luminaires. Click here to learn more about AirLink Blue. Luminaire Shown with IMSBT Surface Wiring Box Luminaire Shown with PCI IMSBT PCI Wet location rated surface wiring box features 1/2” and 3/4” knockouts for surface conduit Page 1 of 1 EXHIBIT “A” PMW 22-008 LEGAL DESCRIPTION PARCEL ‘A’ Being all of Parcel “A” together with Parcel “B” of Certificate of Compliance, Waiver of Parcel Map PMW 17-063 recorded on March 27, 2018 as Document No. 2018-0114562 of Official Records, County of Riverside, State of California. CONTAINING 6.13 Acres, more or less. AS SHOWN ON EXHIBIT “B” attached hereto and by this reference made a part hereof. SUBJECT TO all Covenants, Rights, Rights-of-Way and Easements of Record. This legal description and accompanying plat were prepared by me or under my direction in conformance with the requirements of the Professional Land Surveyors Act. _________________________________ Christopher L. Alberts, PLS 8508 ___________________________ Date FOR REVIEW ONLY CITY OF PALM DESERT ATTENDANCE REPORT Advisory Body: Prepared By: Year Month Date 4-Jan 18-Jan 1-Feb 15-Feb 1-Mar 15-Mar 5-Apr 19-Apr 3-May 17-May 7-Jun 21-Jun 5-Jul 19-Jul 2-Aug 16-Aug 6-Sep 20-Sep 4-Oct 18-Oct 1-Nov 15-Nov 6-Dec 20-Dec DeLuna, Nancy -P P -P P -P P -P -P --P P --P P P P -0 0 Greenwood, John -P P -P P -A P -P -P --P P --P P P P -1 1 Gregory, Ron -P P -P P -A P -P -P --P P --P A P P -2 2 Holt, Lindsay -P P -P P -P P -P -P --P A --P P P P -1 1 Pradetto, Joseph -P A -P P -P P -A -P --P P --P P P P -2 2 Palm Desert Municipal Code 2.34.010: P Present A Absent E Excused -No meeting 2022 2022 2022 2022 2022 Total Absences Oct Nov Dec Planning Commission M. O'Reilly 2022 2022 Twice Monthly: Six unexcused absences from regular meetings in any twelve-month period shall constitute an automatic resignation of members holding office on boards that meet twice monthly. Total Unexcused Absences Jan Feb Mar Apr May Jun Jul Aug Sep 2022 2022 2022 2022 2022