HomeMy WebLinkAboutPedestrian Countdown Signal V
e
CITY OF PALM DESERT
PUBLIC WORKS DEPARTMENT
STAFF REPORT
REQUEST: Pedestrian Countdown Signal
SUBMITTED BY: Mark Greenwood, City Engineer
DATE: November 13, 2003
CONTENTS: Pedestrian Countdown Signal Report
Desert Sun Newspaper Article
Recommendation:
Continue to evaluate Pedestrian Countdown Signal research prior to
installing them in Palm Desert.
Executive Summary:
Pedestrian Countdown Signals are an emerging technology that has been developed
within the last five years or so. Many agencies have conducted experiments under the
auspices of the Federal Highway Administration and within the State of California under
the California Traffic Control Devices Committee. However, most of the research has
been informal in nature; consisting of informal observations with little before and after
study. San Jose State University, in cooperation with the City of San Jose Department of
Transportation, has conducted a thorough analysis of the effects of Pedestrian
Countdown Signals and issued their final report in May 2002. This report represents the
most thorough analysis of Pedestrian Countdown Signals to date and is probably the
most authorative body of work on the subject. A summary of major findings can be found
beginning on page 31 of the report and includes the following observations with
Pedestrian Countdown Signals:
• The percentage of pedestrians that left the curb during the flashing "don't
walk" increased, which is a somewhat negative effect.
• The percentage of pedestrians that reached the far curb on a flashing
"don't walk" also increased, which is a positive effect.
• There was no effect on unusual pedestrian behavior. Pedestrian walking
speed was unaffected.
• Pedestrians apparently do not have a good sense of the time it takes to
cross the street, therefore, the time indicated on the countdown signal
had relatively little meaning.
• Survey indicated that the pedestrians understanding of the flashing "don't
walk" indication actually decreased with the presence of the countdown
indication.
,
Staff Report: Pedestrian Countdown Signals
November 13, 2003
Page 2 of 2
• There was no effect on motorist behavior, either positive or negative.
• There was no discernable effect on pedestrian safety, partially due to the
relatively small sample size of the study.
Therefore, staff recommends that City Council, given the substantial extra costs of
Pedestrian Countdown Signals and the negligible demonstrated benefits, do not install
these devices at this time.
Su itt d
r\
Mark Gr enwood, P.E. Michael Errante, P.E.
City Engineer Director of Public Works
Approval:
er Cr Carlos Ortega
ACM for Dev opine t Services City Manager
CITY COUNCIL ACTION:
APPROVED DENIED
RECEIVED OTHER
MG/cc MEETING DATE 11-13-03
AYES: Cri+es, F L&S r, iejzl f430ils
NOES: Nckl
ABSENT: /4o l E
ABSTAIN: it!cal E
VERIFIED BY: /e_d)7' I r*
Original on File with Ci Clerk' s Office
*Councilmen Ferguson and Kelly appointed to a
subcommittee to work with staff on further study
to develop a formal recommendation for City Council
action.
From www.desert-sun.com
NEW CROSSWALK SIGNAL "PEDESTRIAN FRIENDLY"
PALM SPRINGS -- A new traffic signal on South Palm Canyon Drive counts down the
seconds remaining for pedestrians to safely cross the street.
The signal, at the pedestrian crossing near the Sonny Bono fountain at Mercado Plaza,
flashes a countdown from nine to zero when the signal changes from walk to a flashing
red hand, reported Palm Springs city traffic engineers.
The signal is the first of its type to be installed in Palm Springs, but there could be more
if the pilot program is successful, officials said.
"We chose that location because it is one of the busiest in terms of pedestrians
crossing," said Richard Jenkins, the city"s traffic engineering coordinator. "We want to
make our city as pedestrian friendly as possible."
The signal cost $388,about $182 more than typical pedestrian signals, and was funded
with gas tax money.
Pedestrian Countdown Signals:
An Experimental Evaluation
Volume 1
1E
Jan L. Botha, Ph.D.
Aleksandr A. Zabyshny
Jennifer E. Day
San Jose State University
Department of Civil and Environmental Engineering
Ron L. Northouse, P.E.
Jaime O. Rodriguez
Tamara L. Nix
City of San Jose Department of Transportation
May 2002
I �
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
BACKGROUND AND INTRODUCTION
The countdown signal displays flashing numbers that count down the time remaining until the
end of the flashing "DON'T WALK" (FDW) interval. The countdown display,which can start
at the onset of either the WALK or the FDW display,reaches zero and blanks out at the onset of
the steady"DON'T WALK"(DW) display. When the countdown starts at the beginning of the
FDW,the duration of the countdown is approximately equal to the pedestrian clearance interval
for the crosswalk(the duration may vary according to local signal timing practice). This issue is
discussed later in this report.
The first installation of countdown signals in California occurred in Sacramento County in 1998.
Since that time,many cities have installed countdown signals. The City of San Jose made a
request to the California Traffic Control Devices Committee (CTCDC)to install these signals on
an experimental basis at five intersections to study their effectiveness. In November 2000, the
request was granted to install the signals at five intersections for testing.
For the San Jose study, the countdown accompanying the FDW display(as illustrated below)
was tested.
111
Ei
cmJ7
WALK FDW DW
According to Huang and Zegeer(1)the principal motivation for the pedestrian countdown signal
is to aid pedestrians in getting out of the street before they would be exposed to oncoming motor
vehicles. However, during deliberation at the CTCDC meeting in June 2001 to develop
standards for the various agencies testing the devices in California, several issues were raised
that needed to be addressed regarding the operation of the countdown signals. The following
questions arose:
Page 1 of 35
1 �
• Pedestrian Countdown Signals Study in the City of San Jose
11 Final Report to the California Traffic Control Devices Committee
• Could the public incorrectly interpret the countdown display to mean that it is permitted
to leave the curb as long as it is possible to complete the crossing before the countdown
reaches zero?
• Would erratic behavior of pedestrians, such as running,hesitating or turning around in
the crosswalk increase?
• Would the incidence of motorists entering the intersection on yellow or red increase?
The above issues were addressed in the San Jose study and are discussed in this report. In
addition, it was considered important to gain some understanding of other related issues, such as
pedestrians' ability to judge how long it would take to clear a crosswalk. To gain perspective on
safety issues, studies of crash history and pedestrian-vehicle conflicts at the study sites were
undertaken.
The objective of this report is to present the results of the study of the performance of the
countdown signals in the City of San Jose, including relevant data gathered at other intersections
in the city, conclusions and recommendations.
The report is presented in two volumes. Volume 1 contains an overview of existing studies and
other relevant literature, the study approach, relevant information on the study sites,results of the
study of pedestrian behavior,motorist behavior,traffic conflicts and crash analysis. An
overview of existing practices for pedestrian signal timing in California,together with
information on incorporating countdown signals in timing procedures,is provided. A summary
of the major conclusions as well as a discussion and recommendations follow. Volume 2
consists of appendices that contain more detailed reports of data collection and analysis.
Page 2 of 35
4
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
REVIEW OF EXISTING DOCUMENTATION
The California Vehicle Code 2002 Edition(2) states the lawful actions of pedestrians when
confronted pedestrian signal displays as:
"(a) `Walk' or Approved `Walking Person' symbol. A pedestrian facing the signal
may proceed across the roadway in the direction of the signal, but shall yield
the right-of-way to vehicles lawfully within the intersection at the time that
signal is first shown.
(b)Flashing or steady 'DONT WALK' or `WAIT' or approved `Upraised Hand'
symbol. No pedestrian shall start to cross the roadway in the direction of the
signal,but any pedestrian who has partially completed crossing shall proceed
to a sidewalk or safety zone or otherwise leave the roadway while the `WAIT'
or 'DONT WALK' or approved `Upraised Hand' symbol is showing."
The code further states that it"..shall be unlawful for any pedestrian to fail to obey any sign or
signal erected or maintained to indicate or carry out the provisions of this code.."
That conventional FDW signals are misunderstood by a significant percentage of pedestrians is a
phenomenon that does not seem to be in dispute. Literature on Canadian crosswalk research
prepared for the U.S. Department of Transportation's Federal Highway Administration(3)
reports that 80 percent of pedestrians surveyed inaccurately interpreted the pedestrian clearance
phase of the FDW display. Robertson,et. al. found that about half of pedestrians understood the
FDW display(4). Surveys in Hampton, Virginia, indicated that 25 percent of pedestrians do not
understand the meaning of FDW signal heads(5).
The results of other studies vary, but the message is the same: many pedestrians are
inappropriately interpreting the message sent by FDW signals. There also seems to be general
agreement regarding the results of the aforementioned misinterpretations. Some people perceive
a flashing hand or a FDW message to mean that they can enter the intersection because the
Page 3 of 35
•
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
steady hand or DW message is not yet displayed(1). Others,particularly the elderly, see the
FDW command and return to their origin curb (6).
The findings on the effectiveness of countdown pedestrian signal heads are less conclusive. The
assumption underlying this variety of pedestrian signal is that pedestrians that know how much
time they have left to cross are better informed and,as a result,make better decisions when
crossing the street. Some research supports this theory; some refutes it.
For instance, a study by the Minnesota Department of Transportation(7)found that crosswalk
signal modifications that included pedestrian countdown signals increased"successful crossings"
from 67 percent to 75 percent, and improvements for the elderly were even more dramatic. It is
noteworthy,though,that a"successful crossing"was defined as a crossing that began during the
WALK or FDW phase of the pedestrian signal and ended before the steady DW indication. The
incidence of pedestrians leaving the curb during the WALK indication and finishing during the
WALK or FDW indication increased less dramatically, from 55 percent before the installation to
62 percent after. Furthermore,the incidence of pedestrians starting on FDW or DW and
finishing after the DW displays, increased from 6 to 12 percent. A majority of pedestrians
indicated that they understood the meaning of the countdown signals.
Study data from San Francisco (4) indicate that the number of pedestrians clearing the
intersection after the FDW phase decreased significantly after countdown installation. It should
be noted that the higher incidence of successful crossings is mostly attributed to pedestrians
quickening their pace in response to the countdown display. The study reports a slight decrease
in the incidence of pedestrians entering the intersection on the FDW from the before to the after
installation periods,as well as decreases in pedestrian/vehicle conflicts and erratic pedestrian
behavior in the crosswalk. Additionally, the report identifies a decrease in pedestrians'
understanding that starting to cross during the FDW phase is a violation. Interestingly, although
92 percent of pedestrians said that countdown signals are "more helpful"than conventional
signals, the proportion of pedestrians who properly interpret the FDW display decreased from 40
percent before to 17 percent after the implementation of the countdown signal. It was also noted
Page 4 of 35
v
0
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
in the study findings that"pedestrians are using the countdown signals to decide when to start to
cross,"but that the presence of the countdown signal did not affect the likelihood of a pedestrian
leaving the curb during the FDW. Pedestrians in San Francisco stated that they found the signal
to be helpful because it showed the time remaining to cross,but the data do not indicate a
significant change in lawful crosswalk entry as a result of the countdown device. Additionally,
the report states that the positive impacts on pedestrians' behavior,particularly that they are not
more likely to leave the curb during the FDW interval, are more significant than pedestrians'
misinterpretation of the FDW display.
Similar findings in Quebec indicate that the presence of countdown devices reduced
pedestrian/traffic conflicts significantly,though the actual significance of the reduction is unclear
because specific data supporting this conclusion was not included in the report(8). Research
was also conducted in the City of Monterey(6) on pedestrian behavior,but only during the after
situation, which does not allow for a comparative analysis. Surveys from the Monterey study
indicated that most pedestrians understood the meaning of the signal, and researchers suggest
that pedestrians who do not understand the signal can"at least...rely on the time indicated on the
countdown to dictate their behavior."
One study conducted in the City of Saint-Laurent in Quebec, Canada, surveyed over 4000
pedestrians and found that 80 percent of pedestrians did not understand the FDW display.
Follow-up research showed that the presence of countdown signal heads did not increase their
understanding. In another study of eight intersections in six Quebec municipalities, a yellow-
silhouetted figure phase was added between the white-silhouetted figure phase(signifying
"WALK")and a red-silhouetted figure phase(signifying"DON'T WALK")to indicate an
interim message, "DON'T BEGIN TO WALK." This study concluded that pedestrians better
understood the message of the tri-colored signal head; however, the incidence of compliance did
not increase. Another study in Toulouse, France, found no significant change in pedestrian
behavior following installation of countdown displays (3).
Research prepared for the Federal Highway Administration(1) indicates that pedestrian
Page 5 of 35
1 t
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
countdown signals had a greater negative than positive impact on pedestrian safety in test sites in
Sacramento County, California. They found that the proportion of pedestrians who complied
with the WALK phase decreased from 82 percent to 68 percent, and the proportion fmishing
after time ran out increased from 11 percent to 17 percent. They also stated that the signal might
be inducing pedestrians to enter the crossing on the FDW. The same study concludes that the
percentage of pedestrians conflicting with oncoming traffic increased significantly,that
pedestrian countdown signals need further testing to ascertain their effects, and that alternatives
other than countdown signals can be more effective in improving pedestrian safety.
From the above discussion, it appears that the countdown signals may cause pedestrians to enter
the crosswalk during the FDW interval. In most cases,there was an indication that the signal
may aid the pedestrians in exiting the crosswalk before the DW interval. However, it is notable
that in some of the studies that emphasized this positive aspect,the proportion of pedestrians
entering the crosswalk inappropriately was not studied. Moreover, in two of these studies,
specific mention was made of the fact that the device was not intended to stop the pedestrians
from entering the crosswalk during the FDW interval. In the case of the San Francisco study,
researchers state that the study alerted them to the potentially-significant incidence of improper
interpretation of the signals bypedestrians,but the report also states that entryon FDW is not the
IP 1� P
City's"official policy" and that the behavioral changes observed after the installation were of
sufficient merit to outweigh the lack of pedestrian understanding of the FDW display. The
statement that San Francisco does not accept entry on the FDW as official policy does not, of
course,prevent the pedestrians from entering the intersection on the FDW.
In several surveys,pedestrians responded that the meaning of the countdown was clear to them,
yet data gathered indicate that the countdown display has made the FDW interval increasingly
unclear. The implication here is that pedestrians show a high degree of confidence that their
interpretations are accurate. Because of this conflict,pedestrian statements regarding
erroneous
g g
the clarity of countdown signals should not necessarily be taken to mean that the installation of
the signal is beneficial. It may just mean that they understand that the signal shows the time
remaining,but not that they are meant to wait if a countdown is displayed.
Page 6 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Or 9 Final Report to the California Traffic Control Devices Committee
BASIC APPROACH TO THE EVALUATION
The San Jose evaluation focused on gaining an understanding of the performance of the
countdown signal in five categories discussed in the introduction. These five categories of
questions are:
• Does the countdown signal aid pedestrians in getting out of the street before they would
be exposed to the danger of oncoming motor vehicles?
• Does the countdown signal cause pedestrians to leave the curb during the FDW phase
because they think that they have time to complete the crossing before the countdown
reaches zero?
• Does the countdown signal reduce erratic behavior of pedestrians, such as running,
hesitating or turning around in the crosswalk?
• Does the countdown signal increase the incidence of motorists entering the intersection
on yellow or red?
• Does the countdown signal increase safety?
The performance of the signal was assessed by conducting operations studies,pedestrian
surveys, conflict analysis and the review of crash data. Where appropriate, studies were
conducted before the installation of the new signal as well as after. The before studies
commenced in March 2001 and continued through May 2001. The after studies took place
during the period September 2001 through March 2002. The countdown signals were installed at
the following intersections (dates of installation are shown in parentheses):
• Market Street& St. John Street(6/12/2001)
• Eleventh Street& San Antonio Street(7/13/2001)
• Santa Clara Street&Twenty-first Street(9/6/2001)
• Market Street& San Carlos Street(9/5/2001)
• Convention Center& San Carlos Street(9/5/2001) (pedestrian crossing)
After the initial "before" studies, it was decided that the intersection of Eleventh and San
Antonio would be omitted, because pedestrian volumes were low. It was decided to use the
Page 7 of 35
Pedestrian Countdown Signals Study in the City of San Jose
1/1 Final Report to the California Traffic Control Devices Committee
available resources to gather more data at other test sites. For a part of the study,comparative
sites, without the countdown signals,were utilized. These sites were the intersections at
Almaden Boulevard& San Carlos Street and at Market& Santa Clara Streets.
Overviews of the study methods are presented in the following sections.
Operations Studies
The operations studies consisted of assessing pedestrian compliance,pedestrian walking speeds
and motorist behavior.
The overall goal of the pedestrian compliance study was to assess the incidence of non-
compliance to the pedestrian signal and unusual or"erratic"pedestrian movements. The
objective of the first part of the pedestrian compliance study was to assess the proportion of
pedestrians arriving during the DW or FDW displays that waited for the WALK signal before
crossing the street. During the second part of the compliance study the proportions of all
pedestrians that entered the crosswalk during the WALK, FDW and DW intervals were
measured. The third part of this study was aimed at measuring the performance of the signal in
getting the pedestrians safely out of the crosswalk. To this end,the numbers of pedestrians
exiting the crosswalk on the WALK,FDW and DW were observed. In the last part of the
compliance study,the proportions of pedestrians running, stopping/hesitating or turning-around
were measured. In addition,the proportion of pedestrians involved in a conflict with a vehicle
was also measured.
Pedestrian walking speeds were measured at the study sites to determine whether, on the
average,pedestrians could be encouraged by the new signal to enter the crosswalk on the FDW
and be rushed to complete their crossing by changes in their behavior. The proportions of
motorists entering the intersection on yellow or red were monitored to determine whether the
new signal increased the number of motorists entering on yellow or red.
Page 8 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
All of the above studies were conducted for the before and after installation situations.
Pedestrian Surveys
The principal objective of the pedestrian surveys was to gain further understanding of the
public's interpretation of the countdown signal.
The pedestrians were asked to estimate the time it would take to cross a street. The intent here
was to determine whether pedestrians could correctly estimate the time that it takes to cross a
particular street. This survey was administered at locations without the countdown device. If
they did underestimate the time to cross,this would imply a negative effect of the countdown
signal in that it may cause pedestrians to enter the crosswalk during the FDW display and into a
situation where they could potentially have insufficient time to cross.
The question was also posed as to whether it was permitted to enter on the FDW, at locations
with and without the new signals. The question was also posed in a slightly different way at the
locations with countdown signals to get a more direct interpretation of the meaning of the
countdown itself.
Safety Studies
An analysis of crashes involving pedestrians was conducted at the study sites, for approximately
three years before installation of the countdown signals, and approximately four months after the
signals were installed. Since there were too few such crashes to make a statistical comparison of
crash characteristics between the before and after periods, the crash reports were read to gain
insight as to whether misinterpretation of the FDW display was responsible for the crashes.
A conflict study was carried out before and after installation to establish any differences in
conflict occurrence between the before and after period. All studies and surveys were first tested
Page 9 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
in the field, and then modified based on this experience. Vehicle and pedestrian volume counts
were conducted where and when appropriate.
THE STUDY SITES
Sketches, showing pertinent site characteristics are presented in Figures 1 through 6. Other
relevant information is provided below for the four principal study sites (those with countdown
signals) as well as for the two supplemental sites (those without countdown signals).
The Principal Study Sites—With Countdown Signals
Market Street& San Carlos Street
Located in downtown San Jose, this intersection is adjacent to the McEnery Convention Center,
the San Jose Civic Auditorium, and Plaza De Cesar Chavez Park. During conventions, high
pedestrian volumes often include many tourists. The Valley Transportation Authority (VTA)
light rail travels through this intersection along San Carlos Street. This is a nine-phase traffic
signal (seven vehicle phases and two light-rail phases), with pedestrian push buttons for all four
pedestrian phases, and is not coordinated with
other signals. The pedestrian phases are timed
as follows:
Pedestrian 4)2 (North-leg crosswalk) has a 9- ozP
04 •
second WALK interval and a 19-second FDW sancados
ENS
interval, followed by a 3-second "Yellow"
interval,and a 1.5-second "All Red" interval. -
Pedestrian 4)4 (East-leg crosswalk) has a 9-
second WALK interval and a 22-second FDW
interval, followed by a 3-second "Yellow" Figure 1. Market&San Carlos
Page 10 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
interval,and a 1-second"All Red" interval.
Pedestrian 4)6 (South-leg crosswalk) has a 9-second WALK interval and a 31-second FDW
interval, followed by a 3-second"Yellow"interval, and a 1.5-second"All Red" interval.
Pedestrian 4)8 (West-leg crosswalk) has a 9-second WALK interval and a 28-second FDW
interval, followed by a 3-second"Yellow" interval, and a 1-second"All Red" interval.
Market Street&St. John Street
Located in downtown San Jose, this intersection is adjacent to the San Jose Post Office, parking
structures, and office buildings. This is a two-phase traffic signal with left-turn pockets on all
four legs, and pedestrian push buttons for both pedestrian phases. This traffic signal is
coordinated with other signals along Market Street, so the WALK interval for the corresponding
pedestrian phase will vary. The pedestrian phases are timed as follows:
1 ti Pedestrian 4)2 (East-leg and West-leg
crosswalks) has a minimum 5-second WALK
1'b xis interval and a 19-second FDW interval,
oaP °a
followed by a 3-second"Yellow" interval, and
e2
°2F tts, a 1-second "All Red" interval.
1)2P1 s Pedestrian 4)4 (North-leg and South-leg
°2F
crosswalks) has a 5-second WALK interval
r� and a 19-second FDW interval, followed by a
11,47
3-second "Yellow" interval, and a 1-second
Figure 2. Market&St.John "All Red"interval.
Page 11 of 35
Pedestrian Countdown Signals Study in the City of San Jose
` Final Report to the California Traffic Control Devices Committee
Santa Clara Street& Twenty-first Street
�A1� r Located just east of downtown San Jose, this
NI} V
02P tz ` intersection is near San Jose Academy High
e4 /l4 School, and lies within both a residential (to
<7 the North and South) and commercial (to the
SantaClara
East and West) area. This is a two-phase
°4
2P a2P traffic signal with no left-turn pockets,
\-4,- \ although left-turn movements are permitted
from all approaches. There is no vehicle
detection system, and no pedestrian push
Figure 3. Santa Clara&21 st
buttons. This traffic signal is coordinated with
other signals along Santa Clara Street, so the WALK interval for the corresponding pedestrian
phase will vary. The pedestrian phases are timed as follows:
Pedestrian 4)2 (North-leg and South-leg crosswalks) has a minimum 5-second WALK interval
and a 14-second FDW interval, followed by a 3-second "Yellow" interval, and a 1-second "All
Red" interval.
Pedestrian 4)4 (East-leg and West-leg N
crosswalks) has a 5-second WALK interval
and a 12-second FDW interval, followed by a NI",
3-second "Yellow" interval, and a 1-second r
441 g
"All Red" interval. 4-
Convention�e„r ....,r
Light Rail Smtmn .
Convention Center&San Carlos Street Stncartos
a41
This is a mid-block signalized pedestrian
crossing located in downtown San Jose on San
Carlos Street between Market Street and Figure 4. Convention Center& San Carlos
Page 12 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Almaden Boulevard. The crosswalk extends from the San Jose Civic Auditorium (on the north
side of San Carlos) to the McEnery Convention Center and the main branch of the San Jose
Public Library on the south. During conventions, high pedestrian volumes often include many
tourists. The VTA light rail travels along San Carlos through this pedestrian crossing, with a
light rail station located just west of the crosswalk. This is a four-phase traffic signal that utilizes
pedestrian push buttons.
Pedestrian (1)4 has an 8-second WALK interval and a 26-second FDW interval, followed by a 3-
second "All Red" interval.
Supplemental Sites—Without Countdown Signals
Almaden Boulevard& San Carlos Street N
9
Located in downtown San Jose, this � 4 b
intersection is adjacent to the Center for the a2P AZ l
OHP / —_—_
Performing Arts, the San Jose Civic San Carlos <1--
Auditorium, the Hilton & Towers Hotel, and
a public parking lot. During events at the
city facilities located at and near this oHP 34:7,G6P
intersection, there are high pedestrian 1 ^i¢
volumes, including many tourists. The VTA I I V"
light rail travels through this intersection
Figure 5. Almaden& San Carlos
along San Carlos Street. This traffic signal
utilizes conventional pedestrian signals (without countdown) and was selected for pedestrian
surveys at a non-countdown signal location due to it's similar geometric, geographic, and traffic
signal design and timing characteristics with Market Street & San Carlos Street. This is a ten-
phase traffic signal (eight vehicle phases and two light-rail phases), with pedestrian push buttons
for all four pedestrian phases, and is not coordinated with other signals. The pedestrian phases
are timed as follows:
Page 13 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Pedestrian 02 (North-leg crosswalk) has a 9-second WALK interval and a 30-second FDW
interval, followed by a 3-second "Yellow" interval, and a 1-second"All Red" interval.
Pedestrian 04 (East-leg crosswalk) has a 9-second WALK interval and a 28-second FDW
interval, followed by a 3.5-second"Yellow"interval, and a 1-second"All Red" interval.
Pedestrian 06 (South-leg crosswalk) has a 9-second WALK interval and a 33-second FDW
interval, followed by a 3-second"Yellow" interval, and a 1-second"All Red" interval.
Pedestrian I8 (West-leg crosswalk)has a 9-second FDW interval and a 27-second FDW interval,
followed by a 3.5-second"Yellow"interval, and a 1-second"All Red" interval.
Market Street&Santa Clara Street
ti
Located in downtown San Jose, this
intersection is adjacent to office buildings and ' 4 b
ZP C `
near a variety of downtown business
08p04
establishments. This traffic signal utilizes
.„5,
conventional pedestrian signals (without
Sm�ta CLth,
countdown) and was selected for pedestrian % "'
yoev n8P 7
surveys at a non-countdown signal location ��� a�
due to it's similar geometric, geographic, and
traffic signal timing characteristics with
Market Street & St. John Street. This is a six Figure 6. Market& Santa Clara
phase traffic signal with protected left-turns on Market Street, left-turn pockets on Santa Clara
Street, and pedestrian push buttons for all pedestrian phases. This traffic signal is coordinated
with other signals along Market Street, so the WALK interval for the corresponding pedestrian
phase will vary. The pedestrian phases are timed as follows:
Page 14 of 35
' 1 �
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Pedestrian (02 (North-leg crosswalk) has a 5-second WALK interval and an 18-second FDW
interval, followed by a 3-second "Yellow" interval, and a 2-second "All Red" interval.
Pedestrian 04 (East-leg crosswalk) has a minimum 5-second WALK interval and a 19-second
FDW interval, followed by a 3-second "Yellow" interval, and a 2-second "All Red" interval.
Pedestrian 06 (South-leg crosswalk) has a 5-second WALK interval and a 18-second FDW
interval, followed by a 3-second "Yellow" interval, and a 2-second"All Red" interval.
Pedestrian 08 (West-leg crosswalk) has a minimum 5-second WALK interval and a 19-second
FDW interval, followed by a 3-second "Yellow" interval, and a 2-second "All Red" interval.
Page 15 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
PEDESTRIAN BEHAVIOR
Pedestrian Compliance
Details of the study methods and instructions are provided in Volume 2,Appendix A, together
with specific results. Pedestrian volume counts are contained in Volume 2, Appendix B.
Peak times for pedestrian and vehicle volumes were chosen for observations and data collection.
For the San Carlos sites,the schedule of conventions at the nearby center was also taken into
account. The expectation was that conference participants would provide study subjects that
would not be regular users.
Proportion Waiting for the WALK
This part of the pedestrian compliance study consisted of assessing the proportion of pedestrians
that arrived during the FDW display and waited for the WALK signal. The intent was to get
some indication as to whether the countdown signal would cause those pedestrians arriving
during the FDW to enter the crosswalk during the same phase.
The results are presented in Table 1. The percentages are based on the total number of
pedestrians that arrived at the crosswalk during the FDW display(those that entered plus those
that waited for the next WALK interval). The percentages of pedestrians that arrived during the
FDW interval and waited for the next WALK interval decreased significantly at three of the four
intersections (statistically different at the five percent level of significance). This trend was more
pronounced for the 21st/Santa Clara and Market/St. John intersections. The pedestrians at these
intersections are more likely to be regular users and may have become familiar with the
countdown signals. It should be noted that the number of pedestrians waiting on the FDW is
relatively small compared to the total number entering.
Page 16 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Table 1. Pedestrian Compliance Summary - Waiting To Cross
Number of pedestrians %of pedestrians(arriving during FDW)
Location arriving at crosswalk that waited for WALK display
e•'
during the FDW display
Before After Before I After Difference
Market&San Carlos 296 279 14.9% 8.6% -6.3%
Santa Clara&21st 106 210 18.9% 2.9% -16.0%
Convention Ctr&San Carlos 69 I 151 11.6% 11.9% 0.3%
Market&St.John 79 _. 220 [ 41.8% 9.1% -32.7%
From the above discussion, it may be concluded that the countdown signal may be causing
people to enter the intersection on the FDW (perhaps when the countdown still displays a high
number that causes the pedestrians to believe that they can still safely cross the intersection).
Proportion Entering Crosswalk During the WALK, FDW& DW Displays
The total numbers of pedestrians entering selected crosswalks on the WALK, FDW and the DW
displays, respectively, were recorded. The results are summarized in Table 2. The proportion of
entries on FDW increased for all four intersections. On the DW interval, the proportion of
entries decreased at three of the intersections. The fact that proportionally more pedestrians
entered on the FDW could be construed to mean that the new signal causes them to enter the
crosswalk during the FDW display. It should be noted though that the differences are relatively
small and are not statistically different at the five percent level of significance.
Table 2. Pedestrian Compliance Summary- Entering Crosswalk
Number of Pedestrians % of Pedestrians %of Pedestrians %of Pedestrians
Location Entering on WALK Entering on FDW Entering on DW
Observed
Before After Before After [ Diff. Before E After Diff. Before After E Diff.
Market&San Carlos '1 2038 1695 78.7% 76.3%', -2.4% 12.4% 15.0% I 2.7% 8.9% 8.6% -0.3%
Santa Clara&21st I 482 1113 72.6% 73.4% 10.8% 17.8% 18.3% 1 0 5% 9.5% 8.3% 1-1.3%
Cony Ctr&San Carlos-I 464 933 49.8% 49.9%'L 0.2% 13.1% 14.3% 1 1.1% 37.1% 35.8% -1.3%
Market&St.John 406 11599 I.82.3% 79.4% 1-2.9% [ 11.3% 12.5% 11.2% 6.4% 18.1% 'I 1.7%._._
Page 17 of 35
•
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Proportion Exiting Crosswalk During the WALK, FDW&DW Displays
The numbers of pedestrians exiting the crosswalk on the WALK, FDW and DW were observed;
Table 3 contains a summary of the results.
Table 3. Pedestrian Compliance Summary — Exiting Crosswalk
Number of ° o o
Pedestrians /°of Pedestrians /o of Pedestrians /°of Pedestrians
Location Observed Exiting on WALK Exiting on FDW Exiting on DW
Before After Before 1 After 'F Diff. Before After Diff. Before After 1 Diff.
Market&San Carlos 1993 1673 0 7% 10.9% 0.2% 86 0% 187.9%, 2.0% 13.4% 11.2%',1-2.2%
Santa Clara&21st 484 1101 33.9% :30.2%' -3.7% 48 3% '155.9%'' 7.6% 17.8% 13.9% 1-3.9%
Cony Ctr&San Carlos 463 909 7 8% 15.1% -2.7% 62.0% 169.1% 7.1% 30.2% 25.9% 1-4.4%
Market&St.John 406 1586 28 1% 123.3% -4.8% 159.6% 167.5% 7.9% 12.3% 9.3% '1-3.0%
The proportion of pedestrians exiting during the FDW indication increased at all of the sites,
while the proportions exiting on the DW decreased. All increases were statistically different at
the five percent level of significance. This may be an indication that pedestrians are changing
their walking behavior and that they use the countdown as an indication of the need to increase
their walking speed. From this viewpoint, the signal may be viewed as beneficial.
Unusual Behavior
The numbers of pedestrians running, stopping/hesitating or turning-around were recorded as well
as the number of pedestrians involved in a conflict with a vehicle. A conflict was defined as any
action by a vehicle that caused a change in the behavior of a pedestrian. The results are
summarized in Tables 4 and 5.
The differences between the before and after results are relatively small and do not show a
pattern. Moreover, since judgment was involved and different observers participated, the results
may also be inconsistent.
Page 18 of 35
•
Pedestrian Countdown Signals Study in the City of San Jose
Le Final Report to the California Traffic Control Devices Committee
Table 4. Pedestrian Compliance Summary - Pedestrian Action
Number of j %of Pedestrians that %of Pedestrians that %of Pedestrians that
und/
Location Pedestrians I Ran while Crossing Stopped/Hesitated Turned to Curb
Returned to Curb
Before After Before ' After Diff.. Before After Diff. Before After Diff.
Market&San Carlos 2038 1695 3.6% 12.8% -0.9% 1.1% 12.8% `1.6% 1 0.1% 0.1% [0.0%
Santa Clara&21st 482 1113 2.3% 3.3% 1.0% 0.6% 'I 0.8% 0.2% l 0.4% 0.0% -0.4%
Cony Ctr&San Carlos 464 933 5.4% I 2.7% -2.7% 5.2% 1 6.5% 1.4% 0.6% 0.1% 1-0.5%
Market&St.John l 406 1599 4 9% 12.7% -2.2% 1.5% 10.6% 1 0.9% 0.2% 0.1% 1-0.1%
Table 5. Pedestrian Compliance Summary - Conflicts
P
Number of %of Pedestrians Delayed %of Pedestrians Hurried
Location Pedestrians Observed due to a Vehicle Conflict due to a Vehicle Conflict
Before After I Before After Difference Before I After Difference
i €
Market&San Carlos 2038 1695 1 1.6% 2.4% 0.7% 1.1% 1 0.5% -0.5%
Santa Clara&21st 482 1113 0.6% 0.7% 0.1% 0.2% 0.6% 0.4%
Cony Ctr&San Carlos 464 933 i 5.0% 0.2% -4.7% 0.0% 0.0% 0.0%
Market&St.John 406 1599 I 2.0% ( 0.4% -1.6% 1.2% 0.3% -1.0%
Pedestrian Walking Speeds
The details of the study procedure and results are presented in Volume 2, Appendix C.
Field studies were carried out to assess actual pedestrian crossing times at several intersections.
Data were gathered at signalized intersections before the devices were installed and then again at
the same intersections after countdown signals were placed. Pedestrians entering a crosswalk
were observed, and their curb-to-curb time was recorded.
The data gathered in this portion of the study were collected to determine if, and to what extent,
the presence of the countdown signal impacts pedestrian crossing speeds. The results are
summarized in Table 6. Figures 7 and 8 illustrate the pedestrian movement codes referred to in
Table 6.
Page 19 of 35
Pedestrian Countdown Signals Study in the City of San Jose
f Final Report to the California Traffic Control Devices Committee
Table 6. WalkingSpeeds Summary(Selected Intersections)
1 Pedestrian I Before After Difference
Movement ____
Location figures iAverage Average - in Average
(see7 and 8) No. of Distance, Speed, Standard No.of Distance, Speed,
Standard Speed,ftis
Samples ft iVs Deviation Samples ftDeviation
A, B 9 98 ; 6.7 1.07 3 98 6.9 F 0.58 0.1
C,D !4 93 ( 5.8 0.52 8 93 5.7 r 1.02 -0.1
Market& E,F 24 88 5.7 1.43 71 88 5.8 1.15 ..._ 0.1
St.John
G,H 15 84 5.8 1.62 0 84 Na I n/a n/a
Summary [ 52 F n/a 5.9 1.41 82 n/a 5.8 I 1.14 [ 0.1
A,B 86 r 38 4.3 I 0.70 52 38 4.9...... I 106 �..._...-0.6 ......._
C,D j 13 F. 45 4.2 1 0.96 [.... 17 45 f 3.6 0.73 f -0.6
Santa Clara G,H
f &21 st 17 38 3.8 0.88 20 38 7-3.8 0.52 0.0
G,H 63 45 3.7 0.98 1.44 0.4
64 45 4.1
Summary 179 Na - 4.0 0.88 -153 n/a 4.3 f 1.24 0.2
C 86 I 100 4.6 0.82 61 100 4.4 1.34 I -0.2
i Cl 42 ( 25 3.5 0.62 19 25 3.2 0.90 ( ......._0.4 ........
C2 53._... ... 33 4.7 1 23 7 33 ._... 4.2... .._ 1.00 ( -0.5
Cony Ctr&
5 100 6.6 1.78 I 9 100 4.4 1.00 [ -2.2
San Carlos D
D1_ ... .i 3 [ 33::. ( 3.9 0.87 [. 1 _..._ 33 ( 3.0 ....__r n/a f........-0.9 ......_
D2 6 25P- 3.4 0.76 7__ 25 [ 3.2 I 1.28 -0.2
Summar
y 195 Na j 4.4 1.11 104 n/a 4.1 1.29 -0.3
Figure 7. Movement Codes Figure 8. Movement Codes
(Standard Intersections) (Convention Center
&San Carlos)
NW Ili NE
N
ril allIP
BMW
I.
SW jtr SE S
I
Data from this portion of the study indicate that pedestrians' crossing speeds are negligibly
affected by the presence of the countdown signal. It is notable that the differences in walking
speeds are much greater when the walking speeds for the different sites are compared. This
reinforces the conclusion that the countdown does not significantly affect walking speeds.
Page 20 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Pedestrian Surveys
Four short surveys were designed to gather data on pedestrians' interpretations of various
intersection features. Pedestrians were selected at random from those who were approaching the
curb to cross at an intersection. The specific instructions, survey forms, and details of the results
are presented in Volume 2, Appendix D.
Survey 1:Perception of Crossing Time/Frequency of Crosswalk Use
The purpose of this survey was to determine whether pedestrians could accurately estimate the
time necessary to traverse an intersection. This survey was conducted at two separate
intersections where no countdown signal was present. The reason for using intersections without
countdown signals for data collection was to eliminate bias from people knowing the design
clearance time,which they would have been able to see at intersections with a countdown
device. Data were collected at Market& Santa Clara Streets, and also at the intersection of
Almaden Avenue& San Carlos Street. The observations were made when large numbers of
pedestrians were expected such as during convention center events.
Pedestrians were asked how many seconds they thought it would take to cross these intersections
and also how often they used the intersection(daily,weekly,monthly,or just that day).
A summary of the results is shown in Tables 7 and 8. The adjusted standard deviation was
measured, where applicable, by discarding the outliners, which were two or more times larger
than the next highest response.
Figure 7. Movement Codes
(Standard Intersections)
The perceived average crossing times for the crosswalks range
NES—
from about three to ten seconds below the design clearance time. NWT NE
Additionally, the intersection width for movements B and F (see
nil
1111
iiFigure 7) are similar, as are widths for movements D and H; !la
however, average perceived times for B and F turned out to be
dissimilar, as did average times for D and H. The results indicate SW 11.113~� SE
Page 21 of 35
Pedestrian Countdown Signals Study in the City of San Jose
LFinal Report to the California Traffic Control Devices Committee
that pedestrians do not have a good sense of the time necessary to traverse an intersection. Also,
a wide range of responses was received, but the standard deviation is reasonably small. The
latter result probably stems from the fact that 64 percent of the pedestrians are daily users.
Table 7. Pedestrian Perception Of Crossing Time
Pedestrian Pedestrian Adjusted Adjusted
Location { Movement Clearance Number of 'Average Standard Adjusted Standard Range
(see fig.7) Time Responses 1 Deviation Average Deviation (seconds)
(seconds)
B 18 12 18.67 14.83 13.67 7.51 5-30
Market& D .........._ . 19 [ 21 20.48 27.53 ( 9.05 4.57 5-20__.. ..
Santa Clara — F . 18 — 8 r_._11.88....._. 7.88.... .r 11.88 7.88 . ..._5-30 ..._.
H ( 19 11 15.45 [.. 715... -tt 15.45 7.15 r .....5-30.......
Almaden& F C f 28 14 13.36 5.75 13.36 5.75 5-25
San Carlos (...__. E 33 j_ 6 F 20.33 j 8.36 E 20.33 8.36 9-35
Table 8. Frequency Of Crosswalk Use Corresponding To Perception Of Crossing Time
Movement Frequency of Crosswalk Use
Location (see fig.7)
No.of Daily Weekly Monthly Just
Responses j Today
B 12 8 1 1 2
D 21 19 2 0 0
Market&Santa Clara F 8 8 0 0 0
H 11 11 0 0 0
Summary 52(100%) 46(88%) 3(6%) 1 (2%) 2(4%)
I C 14 j 0 2 3 9
Almaden&San Carlos r E 6 0 0 1 i5
rSummary ...,( 20(100%) r 0(0%�........_._ 2(10%) ..._...4(20%) [14(70%)
I
Overall Summary r All 1 .......72 100%) 46(64%) I 5(7%) 5(7%) 16(22%)
Overall, it may be concluded that pedestrians do not have a reasonably good sense of clearance
time, and they may be unable to distinguish clearly between the time required for wider streets
and that required for narrower streets.
Survey 2: Understanding of Flashing Hand Display (Without Countdown)
The purpose of this survey was to determine whether pedestrians understand the message
Page 22 of 35
Pedestrian Countdown Signals Study in the City of San Jose
1/11 Final Report to the California Traffic Control Devices Committee
provided by traditional FDW displays without countdown devices. This survey was conducted at
Market& Santa Clara Streets where no countdown signals were present.
Pedestrians were shown a figure of the upraised hand symbol and asked whether or not they
believe it is permitted to enter the crosswalk when the symbol is flashing.
A summary of the results is shown in Table 9. Data collected at these intersections indicate that
a large majority of pedestrians properly interpret the FDW display(without countdown), i.e., that
it is not permitted to enter the intersection on the FDW.
Table 9. Pedestrian Understanding Of Flashing Hand Display (Without Countdown)
Pedestrian Responses Response Percentages
Location _
Permitted Not Permitted Permitted Not Permitted
to Cross1 to Cross to Cross to Cross
Market&Santa Clara 13 39 24% j 76%
Survey 3: Understanding of Flashing Hand Display(With Countdown)
The purpose of this survey was to determine whether pedestrians understand the message
provided by pedestrian signal displays with countdown devices. This survey, which was
conducted at an intersection where a pedestrian countdown signal was present, differs from
Survey 2 only in that the question references a signal with a countdown device,rather than
without. Data were collected at the intersection of Market& St. John Streets.
Pedestrians were shown a figure of the upraised hand symbol with adjacent countdown display
and asked whether or not they believed it is permitted to enter the crosswalk when the symbol is
flashing. The results of the survey are summarized in Table 10.
Table 10. Pedestrian Understanding Of Flashing Hand Display(With Countdown)
Pedestrian Responses Response Percentages
Location
Permitted Not Permitted Permitted Not Permitted
to Cross to Cross to Cross to Cross
Market&St.John 23 33 ; 41% r 59%
Page 23 of 35
. ,
, .
Pedestrian Countdown Signals Study in the City of San Jose
0 Final Report to the California Traffic Control Devices Committee
Data collected at this intersection indicate that pedestrians properly interpret the FDW display
about 59 percent of the time. It is of interest that, in Survey 2,which was conducted at an
intersection with traditional flashing-hand displays,pedestrians properly interpreted the signal 76
percent of the time. These results indicate that the misunderstanding of the conventional FDW
display increases with the presence of the countdown display.
Survey 4:Meaning of the Countdown
The objective of this survey was to understand pedestrian perception of the meaning of a
countdown display, in the context of whether it signifies that they can enter on the FDW.
The surveyor gestured toward a countdown signal, in the process of counting down,then asked
pedestrians about the meaning of the countdown display. They were asked whether they could
begin crossing the intersection if they could finish before the timer counted down to zero or if
they should instead wait for the next WALK signal. They were also asked the frequency with
which they use that particular crosswalk. The results of the survey are summarized in Table 11.
Table 11. Pedestrian Understanding Of Meaning Of The Countdown
Pedestrian Responses Frequency of Crosswalk Use
Location
Walk if Finish Wait for Next Daily Weekly Monthly Just
Before Zero WALK Signal Today
Market&St.John 24 3 18 3 3 3
Cony Ctr&San Carlos 21 8 9 17 1 2
Total 45(80%) 11(20%) 27(48%) 20(36%) I 4(7%) 5(9%)
Data collected at this intersection indicate that most pedestrians improperly interpret the
countdown display. Eighty percent of the respondents said that they could begin the crossing if
they thought they could finish before it counted down to zero. This would indicate that the
intended meaning of this type of signal is widely misunderstood and that the signal may cause
pedestrians to enter the intersection during the FDW.
Page 24 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
MOTORIST BEHAVIOR
The numbers of motorists entering the intersection on yellow or red were monitored to determine
whether the presence of the new signal increased the proportion of motorists entering on yellow
or red. Both the associated direction(in the same direction as the FDW and or countdown
display) and the opposing direction(crossing the associated direction)were observed. However,
observation of the opposing direction was abandoned soon after the study commenced,because
the number of violations was insignificant. Volume 2,Appendix E contains the details of the
study procedures and results. Vehicle volume counts were conducted at the same time. The
counts are presented in Volume 2,Appendix B.
The results for entries on the yellow are shown in Table 12, for red in Table 13, and for yellow
and red combined in Table 14. In all three tables it can be seen that the proportion of violations
decreased after the countdown signals were installed. Since the differences are small and there
would not appear to be a logical explanation for the decrease, it may be concluded that there was
no discernable negative effect from the installation of the signal.
Page 25 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
Table 12. Motorist Behavior --Entering Intersection During Yellow
Total Number of Vehicles %of Vehicles Entering Intersection
Entering Intersection During Yellow Indication
Location (during period observed)
Before After Before After Difference
Market&San Carlos 7339 22162 2.2% 0.7% -1.5%
Santa Clara&21st 5269 13246 0.9% 1.9% 1.0%
Market&St.John 3243 14741 1.1% 0.6% -0.5%
Table 13. Motorist Behavior --Entering Intersection During Red
Total Number of Vehicles %of Vehicles Entering Intersection
Entering Intersection During Red Indication(excluding
Location (during period observed) permitted right-turns on Red)
Before After Before After Difference
Market&San Carlos 7339 22162 0.3% 0.2% -0.1%
Santa Clara&21st 5269 13246 0.6% 0.5% -0.1%
Market&St.John 3243 14741 0.2% 0.1% -0.1%
Table 14. Motorist Behavior --Entering Intersection During Yellow Or Red
Total Number of Vehicles %of Vehicles Entering Intersection
Entering Intersection During Yellow or Red(excluding
Location (during period observed) permitted right-turns on Red)
Before After Before After Difference
Market&San Carlos 7339 22162 2.5% 0.9% -1.6%
Santa Clara&21st 5269 13246 1.5% 2.4% 0.9%
Market&St.John 3243 14741 1.4% 0.7% -0.6%
I I i
Page 26 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
TRAFFIC CONFLICT AND CRASH ANALYSIS
Crash Analysis
An analysis of crashes involving pedestrians and bicyclists was carried out at the intersections
where the countdown signal was installed, for a period of three years before the installation and
for periods varying from four to seven months after the installation. The primary purpose was to
determine whether the countdown signal resulted in any difference in the crash occurrences at
the intersections.
The crash reports were reviewed to determine whether a misinterpretation of the FDW display
played a role in crash patterns. A total of 24 crash reports were reviewed for the before period.
No reported crashes occurred during the after installation period. No evidence was found that
misinterpretation of the FDW played a role in any of the crashes.
Traffic Conflicts
Pedestrian-vehicle conflicts were recorded to gain some additional perspective on the safety
performance of the intersections during both the before and after installation situations. For the
purpose of this portion of the study, a conflict was defined as an event when either a pedestrian
or a vehicle was delayed as a result of an unlawful action by a pedestrian or a vehicle. Conflicts
were recorded during the before and after periods for selected crosswalks and intersections.
Volume 2, Appendix F contains the details of the study procedures and results.
The results are summarized in Tables 15 through 18. Relatively few conflicts were observed and
it can be concluded that the differences between the before and after installation conflict rates are
relatively small. However, there are a few movements (see Tables 15 and 16) where tie
differences are more pronounced and indicate that the countdown signal may have a beneficial
effect, i.e. the conflict rate is reduced in the after installation period. It should be noted, however
Page 27 of 35
- Pedestrian Countdown Signals Study in the City of San Jose
lCTM.' Final Report to the California Traffic Control Devices Committee
that the collection of these data requires judgment on the collector's part. Since several people
collected data, there may be some bias in the results.
Table 15. Traffic Conflicts Summary-Vehicles Approaching From The West
Right J Left �'+___ Straight �L )Straight
Location Turn Turn -I I- i Near I r- Far In
I Before r After Diff. Before After Diff. !Before After Diff. [Before After Diff.
Number of Conflicts
Market&San Carlos 48 19 2 n/a [ 1 4 0 1
Santa Clara &21st 1 ( 0 ( 0 [ 0 ( 3 1 1 0 [ 0
Cony Ctr&San Carlos n/a n/a n/a n/a ( 5 6 F n/a I n/a r
Market&St.John 7 9 2 5 0 0 0 1 0
Number of Conflicts per Hour
Market&San Carlos 6.0 1.9 -4.1 0.3 Na n/a 0.1 0.4 0.3 0.0 0.1 0.1
Santa Clara&21st 0.3 0.0 ( -0.3 0.0 0.0 0.0 0.8 0.2 [ -0.6 0.0 0.0 ( 0.0
Cony Ctr&San Carlos 0.0 0.0 0.0 0.0 0.0 0.0 2.0 1.5 -0.5 0.0 0.0 ( 0.0
I Market&St.John I 4.7 11.1 -3.5 I 1.3 0.6 I -0.7 I 0.0 10.0 0.0 I 0.0 0.0 0.0
Table 16. Traffic Conflicts Summary-Vehicles Approaching From The East
Right Left - I_ Straight Straight
Location Turn r Turn Near Far -r
[Before [After Diff. Before `After 1 Diff. [Before After Diff. Before After Diff.
Number of Conflicts
Market&San Carlos 4 n/a 0 n/a 0 n/a 0 n/a
Santa Clara&21st 2 1 1 10 I 0 1 0 2
Cony Ctr&San Carlos I n/a n/a Na I n/a [ [ 9 0 Na n/a
Market&St.John 0 [ 3 _ F 17 28 ( 1 ( 0 0 1 F
Number of Conflicts per Hour
Market&San Carlos 0.7 n/a n/a 0.0 n/a Na 0.0 n/a n/a 0.0 n/a n/a
Santa Clara&21st F 0.5 i 0.2 -0.3 ( 0.3 0.0 -0.3 0.0 0.2 0.2 0.0 0.3 0.3
Cony Ctr&San Carlos n/a n/a n/a n/a n/a 1 n/a 3.6 0.0 3.6 n/a n/a n/a
I Market&St.John 0.0 0.4 0.4 111.3 3.5 I -7.8 I 0.7 10.0 I -0.7 I 0.0 10.1 0.1
Page 28 of 35
Pedestrian Countdown Signals Study in the City of San Jose
cFinal Report to the California Traffic Control Devices Committee
Table 17. Traffic Conflicts Summary-Vehicles Approaching From The North
Right _1jJ L Left -1 L'4- Straight Straight _ I
Location Turn 11 Turn -1 Near -1 f- Far F
Before After Diff. Before After Diff. Before After 1 Diff. Before After ( Diff.
Number of Conflicts
Market&San Carlos 12 19 3 1 j 1 18 1 2
Santa Clara &21st 0 2 3 7 1 2 I 1 0
Cony Ctr&San Carlos Na Na n/a Na n/a n/a i n/a Na
Market&St.John 0 ( 0 2 3 0 1 0 5
Number of Conflicts per Hour
Market&San Carlos 1.5 1.9 0.4 0.4 0.1 -0.3 0.1 1.8 j 1.7 0.1 0.2 0.1
Santa Clara&21st 0.0 ( 0.3 0.3 0.8 1.2 I 0.4 0.3 0.3 0.1 0.3 0.0 -0.3
Cony Ctr&San Carlos n/a n/a n/a ( n/a n/a n/a n/a ( n/a I n/a n/a n/a n/a
Market&St.John i 0.0 0.0 0.0 1.3 0.4 -1.0 0.0 j 0.1 0.1 0.0 0.6 0.6
Table 18. Traffic Conflicts Summary- Vehicles Approaching From The South
Right -I L_ Left --0 L Straight _I L Straight _44_
II
Location Turn 7 �r1- Turn i- t - Near Far -1 1 7
Before 1 After Diff. Before After I Diff. Before After Diff. 1 Before After Diff.
i Number of Conflicts
Market&San Carlos 5 1 n/a 6 5 4 { n/a 1 n/a
Santa Clara&21st f 2 2 4 3 3 0 0 0
Cony Ctr&San Carlos n/a Na n/a Na n/a n/a n/a n/a
Market&St.John 1 2 0 1 0 5 ( 0 1
Number of Conflicts per Hour
Market&San Carlos 0.8 n/a n/a 0.8 0.5 -0.3 0.7 Na n/a 0.2 Na n/a
Santa Clara&21st 0.5 0.3 -0.2 1.0 0.5 -0.5 0.8 0.0 -0.8 0.0 0.0 0.0
Cony Ctr&San Carlos n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a `
Market&St.John 0.7 0.3 1 -0.4 ' 0.0 0.1 i 0.1 0.0 0.6 0.6 1 0.0 i 0.1 0.1
Page 29 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
PRACTICE FOR PEDESTRIAN SIGNAL TIMING IN CALIFORNIA
Practices for calculating the pedestrian clearance interval, and timing the FDW interval, vary
among California jurisdictions. The distance pedestrians travel to cross a street(in feet), divided
by four(fed per second), is a generally accepted method of calculating the pedestrian clearance
interval. But there is some flexibility in determining the distance across a street,as well as
including vehicle yellow time in the pedestrian clearance interval when timing the FDW interval.
Inquiries to several California municipalities illustrate the variations in these practices. Both the
City of San Jose and the City of Stockton do not include vehicle yellow time in the pedestrian
clearance interval and generally measure the crosswalk from curb to curb when calculating the
time of the FDW interval. The City of Berkeley does not include yellow time in the pedestrian
clearance interval and generally measures the crosswalk from curb to the middle of the farthest
traveled lane. The City of Fountain Valley includes yellow time in the pedestrian clearance
interval and generally measures the crosswalk from curb to curb. The City of Oakland includes
yellow time in the pedestrian clearance interval and generally measures the crosswalk from curb
to curb, subtracting the parking lane width(at far end) and half of the farthest traveled lane. The
City of Walnut Creek generally includes yellow time in the pedestrian clearance interval (except
at certain intersections such as school and hospital crossings), and crosswalks are measured from
curb to the middle of the farthest traveled lane.
These various practices affect the initial time displayed by the countdown signals. For example,
a countdown signal accompanying the FDW interval for a crosswalk measuring 80 feet from
curb to curb, 68 feet from curb to middle of farthest lane,with a 4 second vehicle yellow time,
would begin counting down at 20(in San Jose and Stockton),at 17 (in Berkeley), at 16 (in
Fountain Valley),and at 13 (in Walnut Creek and Oakland). In all of these cases,current
pedestrian signal timing guidelines are complied with, although the amount of time pedestrians
have to cross once the FDW is displayed would be different depending upon the jurisdiction.
However, it should be noted that if the pedestrian were to see 13 seconds on the countdown
device in Walnut Creek and San Jose respectively,the remainingtime to cross would be the
same, notwithstanding the fact that the start time in San Jose would be 20 seconds.
Page 30 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
SUMMARY OF MAJOR FINDINGS
The following are major findings identified in the study:
Pedestrian Behavior
• The percentage of pedestrians that arrived during the FDW interval and waited for the walk
signal decreased significantly after the countdown signal was introduced. This trend was
more pronounced at intersections where there were likely to be more regular users adjusting
to the new signals. The countdown signal may be causing people to enter the intersection on
the FDW,particularly when the countdown still displays a high number, by making
pedestrians feel that they can still safely cross the intersection.
• The proportion of entries on FDW increased for all intersections,but the differences were
relatively small. The proportion of pedestrians exiting during the FDW indication increased
at all of the sites,while the proportions exiting on the DW decreased. This may be an
indication that pedestrians used the information conveyed by the timer to adjust their walking
speeds in order to clear the intersection before the DW phase.
• There was little difference in the before-and-after proportions of unusual activity,i.e. of
pedestrians running, stopping/hesitating turning-around and pedestrians involved in a conflict
with a vehicle. A conflict was defined as any action by a vehicle that caused a change in the
behavior of a pedestrian.
• Pedestrians' crossing speeds were negligibly affected by the presence of the countdown
signal. The change in average walking speeds from before to the after installation, at
individual intersections, is small compared to the variation of walking speeds among
different intersections. This leads to the conclusion that other factors have a far greater effect
on walking speeds than the countdown signal. Those factors can vary and were not recorded
in this report.
• Pedestrians do not have a reasonably good sense of clearance time, and they may be unable
to distinguish clearly between the time required for wider streets and that required for
narrower streets.
Page 31 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
• At locations without a countdown signal,when pedestrians were asked whether it was
permitted to enter a crosswalk on the FDW, 76 percent correctly responded"no". When the
same question was asked at location with a countdown device, 59 percent correctly
responded"no". This disparity in understanding of the signals indicates that the countdown
device may result in pedestrians believing that they may enter the intersection during the
FDW. When the question was posed in a different way,i.e. whether one was allowed to
enter the crosswalk on FDW if the crossing could be completed before the countdown went
to zero, 80 percent incorrectly responded"yes". This also indicates that more pedestrians
believe it is permitted to enter the crosswalk during the FDW display with a countdown
signal.
Motorist Behavior
Observation of motorist signal violations (entering in yellow or red) showed no discernable
negative effect from the installation of the signal.
Safety Performance
An analysis of crash reports for a period of approximately three years before the installation of
the signal and approximately four to seven months after, showed no evidence that
misinterpretation of the FDW or the countdown device played a role in any of the crashes.
The pedestrian-vehicle conflict study, wherein a conflict was defined as an event when either a
pedestrian or a vehicle was delayed as a result of an unlawful action by a pedestrian or a vehicle,
showed that the differences between the before and after conflict rates(conflicts per hour) are
relatively small. There are a few movements where the differences were more pronounced and
indicate that the countdown signal may have a beneficial effect, i.e. the conflict rate is reduced in
the after period. It should be noted,however that the collection of these data requires judgment
on the collector's part. Since several people collected data,there may be some bias in the results.
Page 32 of 35
Pedestrian Countdown Signals Study in the City of San Jose
Final Report to the California Traffic Control Devices Committee
DISCUSSION OF MAJOR FINDINGS
The studies of pedestrian behavior indicated that the presence of a countdown signal caused
more pedestrians to enter the crosswalk on the FDW indication,which may be viewed as
negative since it results in an unlawful action. It can also cause some pedestrians to step into the
crosswalk and not be able to clear the intersection before being confronted with a conflicting
green indication for vehicles. However, there was also an indication that a larger proportion of
pedestrians are now completing their crossing on the FDW. This result may be construed as
positive, since it would seem that more pedestrians get out of the crosswalk before the DW and
are using the additional information provided by the countdown signal to complete their
crossings in the time provided. It should be noted, that completing a crossing before the DW
reduces the chances for pedestrians to be confronted with conflicting vehicle movements. This
reduction appears to be greater than the increased proportion of pedestrians entering the
crosswalk during the FDW.
The pedestrian survey results showed that the pedestrians interpreted the meaning of the FDW
indication, when used in conjunction with the countdown signal, differently than they interpreted
the FDW indication with no accompanying countdown device. Pedestrians appear to believe that
it is permitted to cross if they can complete the crossing before the countdown reaches zero.
This may be an indication that pedestrians believe the countdown signal provides more
information from which to make a decision,thus shifting the importance from the FDW display
to the countdown signal.
These conclusions are generally borne out by the results obtained in other studies.
Page 33 of 35
Pedestrian Countdown Signals Study in the City of San Jose
9 Final Report to the California Traffic Control Devices Committee
RECOMMENDATIONS
It should be kept in mind that the real benefits of a countdown signal would consist of a
reduction in pedestrian-related crashes connected to the new signal. Determining the extent of
such benefits would probably be difficult in the short term, since pedestriarrrelated crashes are
relatively rare occurrences and establishing a reliable database would require an extensive effort
over several years. It is therefore unlikely that substantially better data will become available
soon for decision-making regarding the implementation of the countdown signal. Consequently,
the results of current studies will therefore have to suffice. Since there are apparently both
advantages and disadvantages to the implementation of the countdown signal in its current form,
an appropriate strategy may be to implement the signal but to address the associated problems
directly.
Potential solutions could include educating the public on the meaning of the countdown display
and modification of the countdown signal to display the initial walk interval (counting down) in
green, followed by the pedestrian clearance interval (counting down)in red, without the
conventional pedestrian symbols.
Page 34 of 35
Pedestrian Countdown Signals Study in the City of San Jose
1/1 Final Report to the California Traffic Control Devices Committee
REFERENCES
1. Huang,H.,Zegeer, C. An Evaluation of Pedestrian Countdown Signals. A Report Prepared
by The University of North Carolina at Chapel Hill Highway Safety Research Center for the
Federal Highway Administration. February 1999.
2. California Vehicle Code. California Department of Motor Vehicles.
http://www.dmv.ca.gov/pubs/vctop/d11/vc21456.htm
3. Canadian Research on Pedestrian Safety. U.S.Department of Transportation. Pub. No.
FHWA-RD-99-090. McLean,VA. December 1999.
4. San Francisco Pedestrian Countdown Signals:Preliminary Evaluation Summary. A Report
Prepared by DKS Associates for the San Francisco Department of Parking and Traffic.
September 13,2001.
5. Bower,Nancy. "What Works in Big Cities?" Online posting. Center for Transportation
Policy,NYU. http:///www.bikefed.org/abstracts/ab 46.html
6. Leonard,J., Juckes,M., Clement,B. Safety&Behavior: Behavioral Evaluation of
Pedestrians and Motorists Towards Pedestrian Countdown Signals. A Report Prepared by
Dessau-Soprin Inc. for the City of Monterey, California. March 1999.
7. Countdown Pedestrian Indication Market Research. A Report Prepared by Cook Research
& Consulting, Inc. for the City of Minneapolis, Minnesota. June 1999.
8. Transportation Research and Development Project Page. Quebec Ministere des Transports.
http://www.mta.gouv.gc.ca/proiet/tab/I040 1 en.htm
Page 35 of 35