HomeMy WebLinkAbout1997-10-06 City Council (24)City of Polo Alto
Manager’s Report
4
TO:
Attention:
HONORABLE CITY COUNCIL
POLICY AND SERVICES COMMITTEE
FROM:CITY MANAGER DEPARTMENT: PLANNING
AGENDA DATE: October 6, 1997 CMR:416:97
SUBJECT:STOP SIGN INTERSECTION SYSTEM UPDATE AND
RECOMMENDATION TO INSTALL STOP SIGNS AT HALE
STREET AND HAMILTON AVENUE
RECOMMENDATIONS
Staff recommends that the Policy and Services Committee recommend the following to
the City Council:
Install stop signs on Hale Street at Hamilton Avenue.
Not to install stop signs at the following four locations:
a. Homer Avenue at Cowper Street,
b. Parkinson Avenue at Harriet Street,
c. Channing Avenue at Webster Street, and
d. Webster Street at North California Avenue
POLICY IMPLICATIONS
The citywide "Stop Intersection.System" was adopted by City Council several years ago.
Consideration of updating the system on a periodic basis is consistent with the Council
priority regarding traffic safety.
BACKGROUND
The citywide "Stop Intersection System" was adopted by the City Council several years
ago. (A map of the Stop Intersection System is available for reference in the
Transportation Division Office, 250 Hamilton Avenue, sixth floor). Changes in traffic
patterns and characteristics, traffic safety needs, and citizen requests, necessitate that the
City Council periodically consider whether to update the system.
Most cities in California use California Department of Transportation (Caltrans) criteria
to determine if the installation of stop signs is warranted. These criteria include review
CMR:416:97 Page I of 5
of traffic volumes and traffic accident history. In.Palo Alto, the justification for a stop
sign on a Lo__qa! street is based on:
1.The Council-adopted "guard and go" policy (installation of stop signs at every other
block to discourage through traffic from neighborhoods),
2. Caltrans criteria (Appendix A of Attachment 1), or
3.Warrants adopted by the City Council in 1973 for installation of traffic control
devices near schools (Appendix B of Attachment 1).
The justification for a stop sign on a collector street in Palo Alto is based either on
Caltrans criteria or Council-adopted criteria for installation of traffic control devices near
schools, for safety reasons. The policy for arterial streets has been that they should not
have stop signs.
Staff receives many requests to install stop signs. All such requests are investigated and
evaluated using the above criteria. As a result of such investigations (including field
observations and review of accidents, traffic volumes, speeds and other relevant data),
safety improvements that diminish the need for stop signs are sometimes made (e.g.,
painting red curbs, trimming bushes, etc.).
While many residents in Palo Alto like stop signs, installation of new stop signs can be
controversial because stop signs require motorists to stop day and night, resulting in
increased delays, noise and air pollution. Historically, staffhas submitted to the Policy
and Services Committee those.requests that:
Staff supports and, therefore, a Council resolution is required to install the stop
signs; and
Staff did not resolve to the satisfaction of residents.
The Policy and Services Committee forwards its recommendations to the Council.
DISCUSSION
This report is a periodic update of the citywide "Stop Intersection System." Included as
Attachment 1, is the "1997 City of Palo Alto Citywide Stop Sign Requests, Evaluation,
and Recommendations" report, which was prepared to summarize requests from citizens
regarding installation of stop signs. Table 1 summarizes staff’s evaluation and
recommendations for requests to install stop signs at five locations.
CMR:416:97 Page 2 of 5
TABLE 1
SUMMARY
1997
Citywide Stop Sign Request and Recommendation
1.Hale Street/Hamilton
Avenue
Hale Street
2.Harriet Street/Parkinson Parkinson Avenue
Avenue
No Yes
i Four accidents in 1996 were right
i angle- type which are susceptible to
i correction by installation of Stop signs.
No No
3.Cowper Street/Homer Homer Avenue No No
Avenue
4.Webster Street/Channing Channing Avenue ’No No
Avenue ............................................................
! Police Department will provide the
i necessary enforcement, as well as place
i the mobile speed display trailer on
i Channing Ave. to remind drivers of their
i speed.
5.Webster Street!N. California Webster Street No No
Avenue
For each intersection, there is an informational sheet (Figures 1-5) that includes a vicinity
map, intersection layout, source of request, background, an evaluation, and staff
recommendation. Detailed information regarding each intersection is contained in
Attachment 1; and, for reference, all five intersections have been assigned a number and
illustrated on the cover page.
All of the requests can be classified into two categories:
1.a perception that there is excessive speeding, and
2.confusion about right-0f-way (R-O-W).
Concerns About Speeding
The requests for installation of stop signs on Parkinson Avenue at Harriet Street
(Intersection No. 2), Homer Avenue at Cowper Street (Intersection No. 3), Channing
CMR:416:97 Page 3 of 5
Avenue at Webster Street (Intersection No. 4) and Webster Street at N. California Avenue
(Intersection No. 5) are due to concerns about excessive speeding on those streets.
However, stop signs are not speed control devices. They are used to resolve right-of-way
problems caused by an excessive amount of traffic or accidents. The existing traffic
conditions at Intersections 2 through 5 do not meet the stop sign warrant criteria for
converting existing two-way stop intersections to four-way stop intersections.
Staff recognizes that drivers do slow down at stop signs and yield the right-of-way to
other vehicles; however, several past studies have indicated that drivers travel as fast or
faster at mid-block locations to make up time lost at stop signs, thus resulting in increased
speeds mid-block. In .addition, noise and air pollution caused by vehicles increase.
Over the next few months, staff will develop a Neighborhood Traffic Calming Program
for both local and collector streets for Council consideration. This program would
establish and formalize City policies relating to the protection of neighborhood streets
from traffic impacts. The purpose of this program is to be more responsive to resident
concerns about traffic problems on local and collector streets, similar to the above
speeding concerns.
Right-of-Way Issues
The request to install stop signs on Hamilton Avenue at Hale Street is due to the apparent
R-O-W confusion caused by the existing two-way stop intersection on Hamilton Avenue.
There were four right-angle type accidents in 1996, which are susceptible to correction
by improving the sight distance or installing stop signs. Since additional signing
improvements have been made in the past and visibility is clear at the intersection,
installation of stop signs on Hamilton Avenue may help reduce the number of right- angle
accidents.
FISCAL IMPACT
Installation of stop signs and associated signing and striping will be accomplished within
the existing budget resources of the Department of Public Works. No additional funds are
needed.
ENVIRONMENTAL ASSESSMENT
Installation of stop signs is categorically exempt trader the California Environmental
Quality Act, therefore no Environmental Assessment is necessary.
ATTACHMENTS
CMR:416:97 Page 4 of 5
1997 City of Palo Alto Citywide Stop Sign Requests, Evaluation, and
Recommendation Report.
Prepared By:Christopher Thnay, Transportation Engineer
Department Head Review:
City Manager Approval:
KENNETH R. SCHREIBER
Director of Planning
and Community Environment
EMII~ HANSON
Assistant City Manager
cc:Joan Holland
Mr. Warren Kallenbach
Mrs. Mello
Cheryl Davis
Harriet Lehrbaum
Janice Banks
CMR:416:97 Page 5 of 5
Attachment I
1997
The City of Pa|o Alto
Citywide
Stop Sign Requests~
Evaluation and
~¢commenda~on
Repor~
Prepared By:
Transportation Division
Christopher Thnay, P.E.
Table of Contents
Executive Summary .........................................................i
Intersection No. 1: Hale Street and Hamilton Avenue ................................1
Intersection No. 2: Parkinson Avenue and Harriet Street ..............................3
Intersection No. 3: Homer Avenue and Cowper Street ...............................5
Intersection No. 4: Channing Avenue and Webster Street .............................7
Intersection No. 5: N. California Avenue and Webster Street ..........................9
Executive Summary
This report is the periodic update of the citywide "Stop Intersection System." It includes an
evaluation and recommendation in response to requests for installation of stop signs from
citizens at five intersections.
The citywide "Stop Intersection System" was adopted by the City Council several years ago.
Changes in traffic patterns and characteristics, and the need to evaluate safety and respond
to citizen requests, necessitates that the City Council periodically consider whether to update
the system.
Most cities in California use California Department of Transportation (Caltrans) criteria
(Appendix A), to determine if the installation of stop signs is wan’anted. These criteria
include review of traffic volumes and traffic accident history. In Palo Alto, the justification
for a stop sign on a local street is based on the following:
(1)
(3)
The Council-adopted "guard and go" policy (installation of stop signs at every
other block tO discourage through traffic from neighborhoods),
Caltrans criteria, or
Warrants adopted by the City Council in 1973, for installation of traffic
control devices near schools (Appendix B).
Stop signs cannot be installed in all circumstances, because they cause traffic delays, air and
noise pollution, and create a general disregard for other traffic signs, when installed where
they are not justified.
The last staff report concerning this issue was forwarded to Council in 1995. Since then,
staff has received many requests to install stop signs. Many of these requests were denied
after conducting detailed investigations at the location. This report focuses on five locations
where Council consideration is requested by the residents.
Four of the five requests concern speeding, and one relates to apparent right-of-way (R-O-
W) confusion. The purpose of stop signs is to assign right-of-way. A stop sign is not a
speed control device. Past studies have shown that to make up time lost stopping at stop
signs, drivers increase their speed mid-block between stop intersections.
Staff has thoroughly investigated each site and recommends installing stop signs on Hale
Street at Hamilton Avenue. A summary for each intersection follows.
Hale Street/Hamilton Avenue: This request has been made by several area residents to
.address the apparent right-of-way (R-O-W) confusion caused by the existing two-way stop
intersection.
Page i
In 1996, there were four accidents at this intersection, all of which were fight-angle type
accidents, which are susceptible to correction by improving the sight distance or installing
stop signs. Since signing improvements have been made in the past and visibility is clear
at the intersection, installation of stop signs on Hamilton Avenue may help reduce the
number of right-angle accidents.
Parkinson Avenue/Harriet Street: This request was made by several residents to help reduce
speeding on Parkinson Avenue. Speed survey data indicate the 85 percentile speed fox" both
directions of travel to be approximately 30 mph, which is similar to or lower than many
residential streets in Palo Alto. Since stop signs are not speed control devices and the
location does not meet Caltrans or "guard and go" criteria, staff does not recommend
installing stop signs on Parkinson Avenue at Harriet Street.
Homer Avenue/Cowper Street: This request was made by a resident to help reduce speeding
on Homer Avenue and facilitate crossing Homer. As a result of the 1995 Stop Sign Request,
Evaluation, and Recommendation Study, new stop signs were installed on Homer Avenue
at Webster Street. Webster Street is only one block east of Cowper Street, therefore,
vehicles that stop on Homer at Webster provide additional time gaps for pedestrians and
vehicles at Cowper to cross Homer. Since stop signs are not speed control devices and the
¯ location does not meet Caltrans or "guard and go" criteria for installation of all-way stop
signs, staff does not recommend installing stop signs on Homer Avenue at Cowper Street.
Channing Avenue/Webster Street: This request was made by a resident to help reduce
.speeding on Channing Avenue and facilitate crossing Channing. The resident indicated that
there are a number of disabled and senior citizens who experience difficulty crossing
Channing at Webster, due to the high speeds of vehicles traveling on Channing. Field
observations indicate that adequate time gaps exist in traffic on Channing at Webster and
crossing Channing Avenue does not appear to be difficult. Since stop signs are not speed
control devices and the location does not meet Caltrans or "guard and go" criteria for
installation of all-way stop signs, staff does not recommend installing stop signs on
Channing Avenue at Webster Street.
In addition, the Police Department has been providing enforcement in the area of Channing
and Webster and has begun placing the mobile speed display trailer on. these streets to
remind drivers of their speed, in an effort to control speed.
Webster Street/N. California Avenue: This request was made by several residents to help
reduce speeding on Webster Street. The residents also reported that some children traveling
on N. California Avenue on their way to Jordan Middle School do not stop at the stop sign
on N. California as they cross Webster Street, which might create a potentially dangerous
situation. Field observations indicated that no visibility problems exist at the intersection.
Also, a review of accident data did not indicate that there is a substantial safety or speeding
problem at the intersection.
Page ii
1997 Stop Sign Requests, Evaluations and Recommendations Study
Intersection No. 1: Hale Street and Hamilton Avenue
Figure 1
Hamilton Av.
Fife Av
Legend
<~]Proposed SignSTOP Location
Existing STOP Sign
Request: Install stop signs on Hale Street at Hamilton Avenue.
Requested By: Several area residents.
Existing Conditions: Hale Street and Hamilton Avenue are two-lane local streets. Hale
Street is a through street, while both the eastbound and westbound approaches on Hamilton
are controlled by stop signs. As Shown above in Figure 1, stop signs currently exist on Hale
Street one block north and one block south of Hamilton Avenue. Field observations indicate
that the intersection is wide and visibility is clear on all approaches to the intersection. The
stop control on Hamilton is clearly visible as a vehicle approaches from either direction.
Page 1
199 7 Stop Sign Requests, Evaluations and Recommendations Study
Evaluation: A review of accident data for the past six years indicates that seven accidents
have occurred at this location; one in 1991, two in 1994, and four in 1996. All four
accidents in 1996 were right-angle type, which are susceptible to correction by improving
the sight distance or installing stop signs.
In an attempt to improve the apparent R-O-W confusion, "2-way" supplemental signs were
installed in December 1990. After the installation of the new signs, the number of accidents
was reduced substantially, except in 1996. Since signing improvements have been made in
the past and visibility is clear at the intersection, installation of stop signs on Hamilton may
reduce the number of fight-angle accidents.
Recommendations:
Hamilton Avenue.
Staff recommends that stop signs be installed on Hale Street at
Page 2
199 7 Stop Sign Requests, Evaluations and Recommendations Stu@
Intersection No. 2: Parkinson Avenue and Harriet Street
l!
Channr~g AV
’l
Walte~ Hays Schoo~
Figure 2
Cultural CenterCultural Center
Legend
~ Proposed STOP Sign Location
~xisthg STOP Sign
Request: Install stop signs on Parkinson Avenue at Harriet Street.
Requested By: Ms. Joan Holland, Parkinson Avenue, Mr. Warren Kallenbach, Harriet
Street and Mr. Rich Baker, a former resident on Parkinson Avenue. All parties expressed
concern that vehicles travel at excessive speeds on Parkinson Avenue.
Existing Conditions: Parkinson Avenue and Harriet Street are two-lane local streets.
Parkinson Avenue nms east-west, between Melville Avenue to the west and Newell Road
to the east. It is a tree-lined street with parking on both sides. Both streets serve a
predominantly residential area, as well as several public facilities such as the Lucie Stern
Community Center, Children’s Library, Rinconada Park, Main Library and the Cultural
Center. As shown above in Figure 2, stop signs currently exist on Parkinson at Melville
Page 3
1997 Stop Sign R, equests, Evaluations and Recommendations Stud),
Avenue, one block to the west, and at Cedar Avenue, approximately one block to the east.
Evaluation: Staff collected speed survey data on Parkinson Avenue to determine the extent
of the speeding problem. The data indicate that the 85th percentile speed is 29 mph in the
westbound direction and 30 mph in the eastbound direction. The 85th percentile speed on
Parkinson Avenue is similar to or lower than many residential streets in Palo Alto and does
not indicate any substantial speeding problem.
The stop sign installation on Parkinson Avenue is consistent with the Council-adopted
"guard and go" policy. Stop signs already exist on Parkinson at every other block. A review
of accident data for the past six years showed no accidents at the intersection. In addition,
the accident and volume data indicate that the location does not meet Caltrans criteria for
converting a two-way stop intersection to a four-way stop intersection.
Use of speed control devices, such as road bumps, is more appropriate to help resolve a
speeding problem. Council previously adopted a set of criteria for installation of road
bumps. Staffhas also evaluated this request for installation of road bumps, but the request
does not meet the adopted criteria.
Recommendations: Staff recommends that stop signs not be installed on Parkinson Avenue
at Harriet Street.
Page 4
1997 Stop Sign Requests, Evaluations and Recommendations Stu~
Intersection No. 3: Homer Avenue and Cowper Street
Figure 3
Request: Install stop signs on Homer Avenue at Cowper Street.
Requested By: Mrs. Mello, Cowper Street. Mrs. Mello is concerned that vehicles are
traveling too fast on Homer Avenue making it unsafe to cross Homer Avenue. The same
request was submitted by Mrs. Mello a couple of years ago. The request was. evaluated at
that time, and a recommendation was included in the 1995 Stop Sign Requests, Evaluation,
and Recommendation Study to the Council. At that time, the location did not meet Caltrans
criteria for installing stop signs.
Page 5
199 7 Stop Sign Requests, Evaluations and Recommendations Study
Existing Conditions: Homer Avenue is a one-way collector street running in the westbound
direction. As shown above in Figure 3, both the northbound and southbound approaches of
Cowper Street at Homer are controlled by stop signs. In addition, stop signs currently exist
on Homer one block east of Cowper, at Webster Street, and one block west of Cowper, at
Waverley Street.
Evaluation: As a result of the 1995 Stop Sign Requests, Evaluation, and Recommendation
Study, new stop signs were installed on Homer Avenue at Webster Street on September 20,
1995. Since vehicles stop on Homer at Webster, which is only one block east of Cowper,
this provides additional time gaps for pedestrians and vehicles at Cowper to cross Homer.
In addition, the accident and volume data indicate that the location does not meet Caltrans
criteria for installing stop signs.
Recommendations: Staff recommends that stop signs not be installed on Homer Avenue at
Cowper Street.
Page 6
199 7 Stop Sign Requests, Evaluations and Recommendations Study
Intersection No. 4: Channing Avenue and Webster Street
Figure
Request: To install stop signs on Channing Avenue at Webster Street.
Requested By: Ms. Cheryl Davis, Channing Avenue. Ms. Davis indicated that there are a
number of persons with disabilities and senior citizens who have experienced difficulties
crossing Channing Avenue near Webster Street, due to the high speed of vehicles traveling
on Channing.
Existing Conditions: Channing Avenue is a one-way collector street running in the
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1997 Stop Sign Requests, Evaluations and Recommendations Study
eastbound direction, with posted speed.limits of 25 mph. As shown above in Figure 4,
traffic signals exist on Channing one block east of Webster, at Middlefield Road, and two
blocks west of Webster, at Waverley Street. In addition, the northbound and southbound
approaches of Webster Street at Channing are controlled by stop signs
Evaluation: Field observations indicate that no visibility problems exist at the intersection.
The level of pedestrian and bicycle activity is low. A review of accident data for the
intersection over the past six years showed only an average of one accident per year. Of
these, only one accident (which occurred in 1994) could be attributed to traveling at an
unsafe speed. The number of accidents does not indicate that there is a substantial safety or
speeding problem at this intersection. In addition, the accident and volume data indicate that
the location does not meet Caltrans criteria for installing stop signs.
In addition, the Police Department has been providing enforcement in the area of Channing
and Webster, and has begun placing the mobile speed display trailer on these streets to
remind drivers of their speed, in an effort to control speed.
Recommendation: Staff recommends that stop Signs not be installed on Channing Avenue
at Webster Street.
Page 8
199 7 Stop Sign Requests, Evaluations and Recommendations Study
Intersection No. 5: N. California Ave and Webster Street
Figure 5
David Starr
Jordan Jr, High
Request: To install stop signs on Webster Street at N. California Avenue.
Requested By: Mrs. Harriet Lehrbaum, N. California Avenue and Ms. Janice Banks,
Webster Street.
Existing Conditions: Webster Street is a two-lane, north-south, residential street with
posted speed limits of 25 mph. Webster Street is a through street, while both the eastbound
and westbound approaches of N. California Avenue are controlled by stop signs. As shown
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199 7 Stop Sign Requests, Evaluations and Reeommendations Study
above in Figure 5, stop signs currently exist on Webster Street one block nol~h and one block
south of N. California Avenue. Field observations indicate that no visibility problems exist
at the intersection.
Evaluation: A review of accident data for the intersection over the past six years showed
an average of less than one accident per year. The number of accidents does not indicate that
there is a substantial safety or speeding problem at this intersection, and the accident and
volume data indicate that the location does not meet Caltrans criteria for installation of stop
signs. In addition, the stop installation on Webster Street is consistent with the Council-
adopted "guard and go" policy, because stop signs exist one block away from N. California
Avenue in each direction.
Recommendation: Staff recommends that stop signs not be installed on Webster Street at
N. California Avenue.
Page 10
CALTRANS STOP SIGN WARRANT
Multi way STOP signs
The "Multi way Stop" installation may be useful at some locations. It should ordinarily be used
only where the volume of traffic on the intersecting roads is approximately equal. A traffic
control signal is more satisfactory for an intersection with a heavy volume of traffic.
POLICY
Any of the following conditions may warrant a Multi way STOP sign, installation:
Where traffic signals are warranted and urgently needed, the Multi way stop may be an
interim measure that can be installed quickly to control traffic while arrangements are
being made for the signal installations.
An accident problem, as indicated by five or more reported accidents within a 12 month
period of a type susceptible to correction by a Multi way stop installation. Such accidents
include right and left-turn collisions as well as right-angle collisions.
3.Minimum traffic volumes
(B)
(c)
The total vehicular volume entering the intersection from all approaches must
average at least 500 vehicles per hour for any 8 hours of an average day, and
The combined vehicular and pedestrian volume from the minor street or highway
must average at least 200 units per hour for the same 8 hours, with an average
delay to minor street vehicular traffic of at least 30 seconds per vehicle during the
maximum hour, but
When the 85th-percentile approach speed of the major street traffic exceeds 40
miles per hour, the minimum vehicular volume warrant is 70 percent of the above
requirements.
Appendix B
AN EXCERPT FOR STOP SIGN JUSTIFICATION FROM THE CITY COUNCIL
ADOPTED WARRANTS FOR TRAFFIC CONTROL DEVICES NEAR SCHOOLS
Rccommendations and assign priorities to the City Manager and/or the Superintendent of the
P,,ao Alto Unified School District for the application of traffic control devices. The analysis of
the need for some form of special protection for a school crossing depends upon the following
two assumptions:
ao The maximum delay a child should be expected to accept should be no greater than that
which would be experienced ifa traffic control signal, timed so as to provide an adequate
crossing interval, were located at the crossing under study.
bo Some form of device is essential when ’the number of adequate gaps in the traffic stream
during the period the children are using the crosswalk is less than the number of minutes
in that same period of time. That is, gaps less frequent than one per minute represent
a situation that may require some form of warning or control device or measure.
Information developed from field studies and measured against the various traffic control
device warrants will determine the type of protectivemeasure that will be physically
installed or established at the crossing. Generally, the policy for the installation of these
devices is as follows:
A.School pedestrian non-control measures
1. Types available
Signs and Marl~ings
Flashing Signals
Pedestrian Walkways
Variable Speed Zones
~2.The above devices will be installed at those school locations wherein the
condition of traffic, i.e., speed, volume, street width and vehicle gap, having
been reviewed by an engineering survey, are found to:
a.Produce frequent and adequate vehicle gaps such that pedestrians may
safely cross the street without additional controls being present.
b. The unobstructed sight distance to the crosswalk is more than that
’ shown for speeds indicated:
25 mph 170 feet
30 mph 200 feet
35 mph 235 feet
40 mph 275 feet
B.School pedestrian traffic control measures and devices
1. Types available
Pedestrian grade separation
School safety patrol
Separated walkways
Stop intersection
Traffic signal system
Transportation
2.The foregoing control measures and devices are to be considered when the
conditions of traffic exceed those conditions listed under warning devices
(non-control measures).