HomeMy WebLinkAbout2000-12-18 City Council (25)City of Palo Alto
City Manager’s Report2
TO:HONORABLE CITY COUNCIL
FROM:CITY MANAGER DEPARTMENT: PLANNING AND
COMMUNITY ENVIRONMENT
DATE:DECEMBER 18, 2000 CMR:453:00
SUBJECT:ADOPTION OF PROPOSED CROSSWALK GUIDELINES AT
UNCONTROLLED INTERSECTIONS
RECOMMENDATION
The Planning and Transportation Commission unanimously recommend that the Council
adopt proposed guidelines for the evaluation oJ requests to mark crosswalks at uncontrolled
intersections.
PROJECT DESCRIPTION
Council instructed staff to adopt a set of criteria for marking and enhancing the safety of
crosswalks at uncontrolled intersections. These are intersections not controlled either by
stop signs or traffic signals.
COMMISSION REVIEW AND RECOMMENDATIONS
The attached staff report and guidelines were presented to the Planning and Transportation
Commission at the November 8, 2000 meeting. The Commission unanimously supported
the proposed guidelines. One concern raised by the Commission was the need for staff to
pay particular attention to special need generators, such as senior centers and schools. The
Commission also suggested that special treatments be provided at marked crosswalks to
provide more safety to pedestrians. These treatments might include median refuges, lighted
crosswalks, and raised crosgwalks.Staff will comply with these suggestions in its
implementation of the guidelines.
ALTERNATIVES
Council could choose not to adopt the proposed guidelines, in which case staffwill continue
to evaluate requests for marked crosswalks on a case-by-case basis.
CMR:453:00 Page 1 of 2
ATTACHMENTS
A. November 8, 2000 Planning and Transportation Commission Staff Report
PREPARED BY: Christopher Tlmay, Transportation Engineer
DEPARTMENT HEAD:
G. EDWARD GAWFk,.)
Director of Planning and
Community Environment
CITY MANAGER APPROVAL:
AUDREY
Assistant to the City Manager
CMR:453:00 Page 2 of 2
TRANSPOR TA TION DIVISION
ATTACHMENT A STAFF REPORT
TO:PLANNING & TRANSPORTATION COMMISSION
FROM:
AGENDA DATE:
SUBJECT:
Christopher Thnay DEPARTMENT: Planning
November 8, 2000
Proposed Crosswalks Guidelines at Uncontrolled Intersections
RECOMMENDATION
Recormnend that Council adopt the proposed guidelines for evaluation of requests to
mark crosswalks at uncontrolled intersections. Criteria for the proposed guidelines take
into consideration attributes such as pedestrian volumes, vehicle gaps, traffic speed and
volumes, visibility, and lighting.
PROJECT DESCRIPTION
The Council instructed staff to adopt a set of criteria for marking crosswalks at
uncontrolled intersections. These are intersections that are not controlled by either stop
signs or traffic signals. At controlled intersections, the traffic signals or all-way stop
signs are the major factors controlling both motorist and pedestrian behavior, rather than
crosswalk markings. At such intersections, there is no evidence that marked crosswalks
help or hinder pedestrian safety. At controlled intersections, limit lines and stop bars help
delrme pedestrian paths and are a factor that an engineer may consider in deciding
whether or not to mark a crosswalk. All signalized intersections in the City have marked
crosswalks. Consequently, guidelines and warrants developed in this report do not apply
to controlled intersections.
The City of Palo Alto follows State policies and the California Vehicle Code (CVC). The
CVC requires the City to follow the national guidelines outlined in the California
Department of Transportation (Caltrans) Traffic Manual. Traffic control devices include
traffic signals, as well as traffic signs and paint markings used in crosswalks. The Traffic
Manual covers all aspects-of the placement, construction and maintenance of every form
of approved traffic control device. The guidelines prescribe five basic requirements for
all devices. They must:
Fulfill a need.
Command attention.
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Convey a clear, simple meaning.
Command respect of road users.
Give adequate time for properresponse.
Consistent use of traffic control devices protects the clarity of their messages. In addition,
it is indicated in the Traffic Manual that uniformity must also mean treating similar
situations in the same way.
These general points should be kept in mind when consideringmarking crosswalks at
uncontrolled Intersections.
Definition of a Crosswalk
The California Vehicle Code states that a "crosswalk" exists at any public roadway
intersection in the State, unless crossings are specifically prohibited. The law does not
make a distinction between marked and unmarked crosswalks at intersections.
Pedestrians generally have the right-0f-way at all intersection crosswalks in the State,
provided the pedestrian does not place himself in immediate danger during the crossing.
This includes both marked crosswalks and unmarked crosswalks at intersections (CVC
§21950). Pedestrians also have the right-of-way at traffic signals, provided they enter
during the WALK phase of the traffic signal (or the green phase, if WALK signals are
not present) (CVC §21456). They continue to have the right-of-way until their crossing is
complete, even if the traffic signal changes to red and serves a conflicting traffic
movement (CVC §21451).
School crosswalks are marked distinctively in Califomia. Yellow paint is used in place of
white, and signing is generally more consistent and more frequently present. This
practice is described in detail in the Caltrans Traffic Manual.
How are Crosswalks at Uncontrolled Intersections Used? ..
At any crosswalk, including unmarked crosswalks, drivers must yield the right-of-way to
pedestrians. Crosswalks are marked mainly to encourage pedestrians to use a particular
path to cross. Studies conducted on the relative safety of crosswalks support minimal
installation of marked crosswalks.
Though it is often unwise to make generalizations, many transportation professionals
have observed that pedestrians normally do not behave as though they expect to be
granted the right-of-way from motorists at unmarked crosswalks. In the absence of
marked crosswalks, it is commonly observed that pedestrians normally wait until the
entire crosswalk is clear to avoid conflict with vehicular traffic. In addition, on divided
highways pedestrians also frequently wait in the median for suitable traffic gaps.
However, it has been observed that pedestrian behavior is often different at marked
crosswalks. Pedestrians frequently begin crossing at marked locations while vehicles are
approaching, requiring the vehicles to slow or stop to avoid the crossing pedestrians.
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Incidences where pedestrians just step out into a marked crosswalk without checking the
road for cars are not uncommon. Staff frequently receives requests for installation of
marked crosswalks, so that motorists will be required to stop for pedestrians. Pedestrians
also frequently assert that motorists will not always stop for them at marked crosswalks.
Staff is also frequently told that motorists are not as courteous as they were many years
ago. In contrast, out-of-state drivers and traffic engineers frequently note that the level
of courtesy between drivers and pedestrians throughout California seems to be much
greater than in other states.
Recent Studies of Marked Crosswalks
In 1970, the City of San Diego studied 400 intersections at which there were both marked
and unmarked crosswalks. The results were surprising, and seemed to indicate that more
accidents occurred in marked crosswalks. A pedestrian safety study conducted in 1997 by
the City of Long Beach also indicated that more accidents occurred in marked crosswalks
compared to unmarked crosswalks. In addition, studies in other cities have supported
these results.
The above studies contribute to the prevailing idea in the traffic community that marked
crosswalks give a false sense of security. Several studies have been conducted to
ascertain the validity of this assumption. Particularly, a 1999 study by the University of
North Carolina and a 1997 study by the City of Santa Ana (the largest sample study of its
kind) have shown that the above sentiment has not been proven. However, extensive
review also indicates research results are still inconclusive in some areas, especially with
regard to uncontrolled, unmarked crosswalks.
Some conclusions to be drawn from recent studies on marked versus unmarked
intersection crosswalks reveal the following:
There are no significant safety differences found for roadways carrying less than
12,000 vehicles per day (vpd). This applies to practically all local streets in Palo Alto.
Unmarked crossing locations generally appear to have better "safety records for roads
with more than two lanes and with traffic levels above 12,000 vpd.
Marked locations were found not to be significantly safer than unmarked locations for
any similar volume and roadway types.
Accident frequency in marked uncontrolled crosswalks is heavily related to vehicular
traffic volume. Accidents are rare for sites with traffic volume lower than 2,700 vpd,
while 94 percent of all accidents occurred at crossings with more than 6,000 vpd.
Four-lane undivided roadways carrying more than 12,000 vpd tend to have the least
satisfactory pedestrian accident experience.
Accident frequency does not correlate with pedestrian traffic volume, in general.
Crosswalks with higher pedestrian volumes are not likely to experience more
accidents than similar crosswalks with lower pedestrian volumes.
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Raised medians and other special design features may be effective in producing better
safety records for marked locations. New treatments, such as actuated warning
systems may also be effective for improving safety experience at marked locations.
The accident rate per pedestrian is much lower for marked crosswalks with high
pedestrian volume. This relationship is true at all vehicular volume ranges.
Existing Policies of Surrounding Cities
A survey of cities in the surrounding area generally indicates a reluctance to mark
uncontrolled crosswalks. Some cities like Sunnyvale have actually been engaged in a
process of taking out uncontrolled marked crosswalks for the past 15 years.
City of Sunnyvale - The City of Sunnyvale has removed most of its uncontrolled
marked crosswalk intersections in the past 15 years, and continues to "chip away" at
removing the remainder, according to the City Traffic Engineer. The underlying
assumption is that pedestrians are much more careful and safe when crossing the
street without the "false sense of security" provided by the two painted white lines.
City of Santa Clara The Staff Engineer believes that crosswalks, especially
uncontrolled intersection crosswalks, give the pedestrian a false sense of security.
Most drivers do not expect pedestrians at uncontrolled intersections. The City is more
inclined to install crosswalks at uncontrolled intersections in industrial areas, because
operators of some facilities insist on having them and there are not that many
pedestrians in the area. Thus far the City of Santa Clara has not had any problems"-
with the uncontrolled intersection crosswalks they have installed. The City will not
install them in residential areas.
City of Ventura - The Ventura guidelines stipulate a minimum peak pedestrian
crossing volume of 40 pph (pedestrian per hour) or 25 pph for each of any 4 hours.
The Ventura Guidelines also stipulate that uncontrolled crosswalks should not be
installed where the 85th percentile speeds exceed 40 mph, or where three or more
lanes in one direction must be crossed. However, a crosswalk may be marked at
locations not meeting these requi~.ements if the City Transportation Engineer deems
that unique circumstances warrant the installation.
City of Mountain View - The City has the following write-up on its web page: "In
most cases a pedestrian in a crosswalk has the right of way over a vehicle, especially
over a vehicle making a right or left turn. However, a pedestrian cannot legally enter a
crosswalk if a vehicle is so close to the crosswalk that it could cause a hazard to the
pedestrian. Unfortunately, it appears that pedestrians behave differently in marked
crosswalks than elsewhere. Many studies have been performed showing that
pedestrians will step into a marked crosswalk without regard to the location or speed
of vehicles approaching the crosswalk. These pedestrians assume they have the right
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of way and that all vehicles will come to a complete stop in advance of the marked
crosswalk. Without the marked crosswalk, pedestrians are much more careful, looking
for any oncoming vehicles and only try to cross the street when it is very safe to do
SO."
Proposed Crosswalk Guidelines at Uncontrolled Intersections
Crosswalk markings should not be used at all intersections. If used extensively, many
marked crosswalks would be underutilized, and motorists would tend to be desensitized
to their presence. This could lead to problems at heavily used crosswalks and detract
from the potential safety value at each location. Crosswalks should be used in general
only at locations where pedestrian activity is significant. This will ensure that motorists
come to associate crosswalk and pedestrian activity. To install crosswalks at locations
where compelling reasons do not exist could put pedestrians at further risk.
Staff’s survey of several studies indicates that there are varying levels of risk and many
locations that present low risk. A different approach is suggested for each general risk
level. The following is a general discussion of each risk category and the typical
pedestrian and traffic volumes, and other traffic factors associated with each.
Low Risk Locations
There is little risk associated with crosswalks at low volume streets (under 2,700 vpd).
There is also little public demand for crosswalks in this range, except near schools and.
other special generators. A threshold that is sensitive to public needs, but results in a low
number of crosswalks, is probably appropriate. The practice recommended in the
Caltrans Traffic Manual in school zones is appropriate (less than one adequate gap per
minute, along suggested route to school). This practice corresponds to a vehicular
minimum of approximately 1,000 daily vehicles and requires a channelized pedestrian
route, as shown on a map of suggested routes to school. This will result in a minimum of
marked crosswalks on low volume streets and heavy school pedestrian usage at most
marked crosswalks. The practice also offers the benefit of exposing school-aged children
to use of marked crosswalks in a relatively secure environment, where there are minimal
consequences to improper crossing behavior. There is also little risk anticipated if this
guideline is violated on limited ocEasions, either by marking or not marking isolated
locations.
Moderate Risk Locations
Generally, risk does not become measurable or predictable for individual locations on an
annual basis until above the 2,700 vpd. Studies show that the pedestrian volume needed
to produce acceptable per-pedestrian rates for this vehicle volume range is very low. This
would tend to endorse the marking of many locations with moderate vehicle and
pedestrian volume, but these locations would likely also have adequate safety records
without markings. Overall, dilution of the effectiveness of crosswalk markings would be
a concern, if they were all marked.
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A clear need to channelize and/or a minimum range of pedestrian volume should apply at
moderate traffic levels to insure ~that markings are applied on a limited basis. Hourly
volumes appear in other studies and guidelines in the 10-40 pedestrian per hour range. A
requirement of 40 pedestrians would seem appropriate, but this limit could be lowered
for special needs. The goal should be to keep the number of marked crosswalks to a
minimum by insuring that there is some foundation for pedestrian demand or
channelization at the locations that are provided.
High Risk Locations
Most studies indicate pedestrian risk becomes more significant at marked crosswalks on
streets carrying more than 12,000 daily vehicles. The pedestrian volume in this range
becomes most significant. The decision to mark the location can be defended upon the
basis of high pedestrian volume, low expected accident rate, and uncertainty about safety
if the location is unmarked.
There should be absolutely compelling reasons before marking such locations.In
addition, such marked crosswalks should also be enhanced by special treatments.
Suggested Crosswalk Warrants at Uncontrolled Intersections
Based on the above considerations, the following warrants have been designed for
evaluating and determining whether marked crosswalks should be installed at
uncontrolled intersections. The criteria take into consideration the total effect of factors
such as pedestrian volumes, vehicle volumes and speed, vehicle gaps, street lighting and
visibility.
The warrants consist of two parts: (A) basic warrants, and (B) point warrants. In order to
qualify for a marked crosswalk at an uncontrolled intersection, a location must meet all
criteria established in the basic warrants and compile at least 16 points or more Under the
point warrants. (see Table 1)
Special treatments such as raised crosswalk, pedestrian refuge island, bulbouts, lighted
crosswalk or actuated warning system should also be considered as part of the approval
process.
Depending on the mix of speed, volumes and location, some of these special treatments
might be mandatory. Staff will take all the information collected during the evaluation
process.
The above guidelines and warrants are to be taken into consideration in evaluation of
requests for marked crosswalk at uncontrolled intersections. However, crosswalks at
uncontrolled intersections may be marked at locations not meeting these guidelines if the
Chief Transportation Official deems that unique circumstances warrant the installation.
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Table 1
City of Palo Alto
Warrants for Mark Crosswalk at Uncontrolled Intersections
(A) Basic Warrants
(i) Pedestrian Volume Warrant
Pedestrian volume at proposed crosswalks should be more than 20 pedestrians per hour (pph) during the
peak pedestrian hour or 15 pph for each of 4 hours.
(ii) Approach Speed Warrant
The 85~ percentile speed at the proposed marked crosswalk locations should be less than 40 mph.
(iii) Visibility Warrant
The unrestricted view for motorists to the proposed marked crosswalk site should have a distance greater
than 200 feet approaching from each direction. This will be a special concern at sites with grades, curves
and other potential significant sight restrictive features.
(iv) Illumination Warrant
Proposed marked crosswalk site must have adequate street lighting near the crosswalk in existence or
scheduled for installation prior to the installation of the marked crosswalk.
(B) Warrant Point System of Criteria (need to compile at least 16 points)
(i) Pedestrian Volume Warrant
Criterion
The total number of pedestrians crossing the
street under the study during the peak
pedestrian hour. This includes pedestrian
volumes at both crosswalks. Crosswalk will
not be installed where the ped volume is less
than 10.
Point Assignment
Pedestrian Total
0-20
21-40
41-60
61-90
91-100
Over 100
Maximum
(ii) General Conditions Warrant
(a) Will clarify and def’me pedestrian routes across complex intersections
(b) Will channelize pedestrians into a significantly shorter route
(c) Will position pedestrian to be seen better by motorists
(d) Will position and ensure pedestrian meets fewer vehicles
(iii) Gap Time Warrant
The number of unimpeded vehicle time gaps
equal to or exceeding the required pedestrian
crossings time in an average five-minute
period during the peak vehicle hour
Computations
Ave. # gaps per 5 min. period
0 - 0.99
1 - 1.99
2 - 2.99
3 - 3.99
4 - 4.99
5 or more
Maximum
Points
0
2
4
6
8
10
10
Points
2
2
2
2
Points
10
8
6
4
2
0
10
(1)Pedestrian Crossing Time = street width from curb-to-curb divided by 4 feet per second
(2) Average number of gaps per five-minute period = Total usable gap time in seconds divided by pedestrian
crossing time multiply by 12.
Note: All the warrants need to be met for installation of marked crosswalks at uncontrolled
intersections.
The Chief Transportation Official also reserves the right to modify any such criteria in
the event that future research makes such modifications necessary.
POLICY IMPLICATIONS
Comprehensive Plan
Installation of crosswalks is consistent with Comprehensive Plan Goal T-3: "Facilities,
Services, and Programs that encourage and Promote walking and Bicycling". It is
specifically supported by Program T-32: "Improve pedestrian crossings with bulbouts,
small curb radii, street trees near comers, bollards, and landscaping to create protected
areas."
ENVIRONMENTAL REVIEW
Installation of crosswalks and related signing is considered to be minor operational
improvement and is therefore categorically exempt under the California Environmental
Quality Act section 15301. Therefore, no environmental assessment is required.
NEXT STEPS
Once these guidelines are approved, staff will use them as a basis to evaluate requests for
installation of uncontrolled intersection crosswalks.
ATTACHMENTS/EXHIBITS
Table 1 in Appendix.
Prepared by: Christopher Thnay, PE, Acting City Traffic Engineer
Reviewed by: Joseph Kott, Chief Transportation Official
Division Head Approval: ~’~-g~_,~
,~ JoSeph I~tt, Chief Transportation Official
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