1990 03 14 TTC Minutes
M E M O RAND U M
TO: Ron Kiedrowski, City Manager
FROM: Frank Reynolds, Director of Public Works~-
City Engineer
DATE: March 27, 1990
SUBJECT: Technical Traffic Committee
A Regular meeting of the Technical Traffic Committee was held at
11:00 A.M. on Wednesday, March 14, 1990. Attendance included:
Members: Lieutenant Ron Dye
Riverside County Sheriff's Department, Indio
Warren Stallard, Branch Office Manager
Riverside County Road Department, Bermuda Dunes
Charles Clay, Director of Transportation
Desert Sands Unified School District, Indio
Roger Hirdler, Community Safety Director
City of La Quinta
Frank Reynolds, Director of Public Works
City of La Quinta
Staff: Steve Speer, Senior Civil Engineer
City of La Quinta
Mr. Reynolds brought the meeting to order at 11:00 A.M.
Old Business item #1 - Report on Safe Route to School
Mr. Reynolds gave a brief review of the City's progress related
to implementing the "Safe Route to School", which essentially is
an 8-foot wide combination bike path/sidewalk in the parkway on
the north side of Calle Tampico between Washington Street and
Park Avenue and on the west side of Park Avenue between Calle
Tampico and Avenue 50. Mr. Reynolds stated that construction of
the street and parkway improvements on Calle Tampico and Park
Avenue in the subject segments is currently underway and will be
Technical Traffic Committee - March 14, 1990
Page 2
completed later this spring by the Landmark Land Company. The
proposed traffic signal at the intersection of Avenue 50 and Park
Avenue will not be installed until late 1990; it is currently
being designed by a consultant to the City. Mr. Reynolds
suggested that it may be necessary as an interim measure f.'or the
school district to man the new intersection with crossing guards
during the months following completion of the Park Avenue
improvements until the new traffic signal is installed latter in
the year.
New Business Item #1 - Consider Request for a 3-Way Stop ait
Washington Street and Avenue 52.
Mr. Reynolds gave a brief history of the request for the ?.-way
stop and explained the short life of the existing intersection as
it relates to the forthcoming realignment of Avenue 52. N[r.
Reynolds then yielded the floor to Mr. Speer who provided an oral
technical presentation supplemented with data documentation.
Along with the data documentation, Mr. Speer presented an
analysis of the traffic count data prepared by Newport Traffic
Studies. It was stated that Caltrans hes ~stabli~hed three
policy criteria that m~ warrant installation of a multi-Fray stop
when any of the criteria are meet; Mr. Speer noted that tY.ie
traffic counts at the intersection meet the traffic volumE~
criteria. Mr. Speer stated that accident data for the
intersection, and average vehicle delay, was unavailable f`or the
meeting but could be researched before a final decision wars made.
Lt. Dye stated that he would research the accident and vehicle
delay data and report back within a few weeks.
Discussion ensued following the presentation. Although traffic
volume at the intersection surpasses the threshold that allows
discretionary installation of a multi-way stop, Lt. Dye, Mr.
Stallard, and Mr. Clay were decidedly against it citing tkiese
reasons:
1. installation of stop signs can, and often do, cause more
accidents than they prevent. The typical problem at a
3-way stop is the through-street traffic (Ave 52)
fails to stop while traffic on the terminal leg off: the
intersection (Washington St) has a false sense of`
security caused by the 3-way stop and enter the
through-street assuming the oncoming traffic willl stop.
The result on a high speed through-street such as
Avenue 52 is severe right angle collisions.
Technical Traffic Committee - March 14, 1990
Page 3
2. The perceived primary benefits of the 3-way stop would
be: reduced delay for traffic leaving Washington Street
and entering Avenue 52, as well as potentially increased
safety for the same motorists. However, these benefits
would accrue to a relative minority during peak i:raffic
hours at the expense of all traffic utilizing Avenue 52
every hour.
On the basis of the forgoing reasons, the consensus of the
committee members is the 3-way stop should not be installed
unless Lt. Dye's forthcoming research into traffic accidents at
the intersection and traffic delay on Washington Street rE:veals
additional evidence that a 3-way stop is warranted.
Post-Meeting Research Input
1. Accidents - In the 21 months prior to 9/30/89, which is
the latest available data, 4 accidents occurred ~aYtich
are potentially attributeable to the lack of a 3--way
stop; the accident rate for this time period is :t.3
accidents per year. None of the accidents involved a
fatality or a severe injury.
2. Vehicle Delay - The Sheriff's Department observed the
intersection during a morning and a evening peak Yiour.
The average delay for southbound traffic at the existing
stop sign was 11.8 and 7.8 seconds respectively.
Please refer to the attached letter from the Sheriff's
Department.
Recommendation
It is recommended that no 3-way stop be installed at this tame.
The policy criteria related to accidents and vehicle delay
compare as follows: 1) five (5) accidents per year is the
threshold that may warrant installation of a 3-way stop, +snd 2)
a thirty (30) second average delay per vehicle is the other
threshold that may warrant installation of a 3-way stop. Because
the accident level and average delay times are significan•t:Ly
below the threshold that may warrant installation of a 3-way stop
coupled with the other reasons mentioned earlier, it is
recommended that no 3-way stop be installed at this time.
In conclusion it can be noted that more than one member of the
Committee and perhaps a high percentage of the general
population as well perceive the intersection as being
Technical Traffic Committee - March 14, 1990
Page 4
potentially dangerous and correctable by installation of <i 3-way
stop; however, traffic statistics do not support the perception.
Perhaps the perception of potential danger by motorists wlto
utilize the intersection adds to a heightened awareness and
actually reduces the accident count. Nevertheless, accidents and
vehicle delay at the intersection should continue to be monitored
and reviewed on an annual basis to detect a change in its
operating characteristics.
New Business Item #2 - Consider installation of stop signs at
certain presently uncontrolled
intersections and the replacement cif a
yield sign with a stop sign.
Mr. Reynolds gave a short oral synopsis supplemented with maps of
the various intersections in question. Discussion ensued
following the presentation. The consensus of the committee
members and relevant supporting reasons are as follows:
Various uncontrolled intersections along Avenida La
Fonda - Stop signs should not be installed. The
intersecting cross streets are unpaved low speed
residential streets with good visibility at the
intersections with La Fonda. The Committee believes the
vehicle code "right of way" rule adequately serves at
these uncontrolled intersections.
2. Type of traffic control to utilize at intersection of
Avenidas Buena Ventura and La Fonda - The existing yield
sign located in the intersection island for southbound
to eastbound traffic should be replaced with a stop
sign. The other existing yield sign at the intersection
for the southbound to westbound traffic should r~amain in
place as is.
The meeting adjourned at 12:00 P.M. (Noon)
MISC\100-01
RIVERSIDE COUNTY
COLS BYRD, SHERIFF
Sheriff
82-695 DR. CARREON BLVD. • INDIO, CA 92201 • (619) 342-8990
March 21, 1990
Mrt. Frank Reyno.eda
City Engineer
78-105 Ca.P,ee Ea.tado
La Qu,i.nta CA 92253
RE: Traffic Survey
Dean. Mrt. Reyno.eda:
Punauant .to .the rtequea.t ob .the Technical Traffic Committee a aunvey was
conducted ob .the intersection of Avenue 52 at Washington ta detenmi.ne delay
time bon. veh.Lclea enten,i.ng Avenue 52 from Washington.
The survey wa6 conducted beam 1:00 A. M. .tn 2:^0 A. M. u.~d a.P,bo brtom 5:00 P.M.
.to 6:00 P. M., Fn,i.day, Martch 16, 1990. The rteauR.ta ace below:
7:00 - 8:00 A.M.
7ota.Y. veh.Lclea enten,i,ng Avenue 52 Srtom Ulaah,i.rtg.ton: 94
Total. delay .time (.i.n aecondal: 1113
Average delay .ti.me pert veh.i.cCe (.in aecondal: 11.84
Total veh.Lclea exceeding 30 aecond a.tandan.d: 6
5:00 - 6:00 P. M.
7atal veh.iclea enten,i,ng Avenue 52 6rtom waahing.ton: 222
Total delay time I-in aeconda): 1732
Average delay .time pert vehicle (-in aeconda) : 7.8
To.taR. veh,ielea exceeding 30 aecond a.tandwcd: 4
Ib I may be o6 bw:.thert aertv.ice .to you, please beet bnee .to contact me.
S.cncertely,
COIS BYRD, SHERIFF
~et.~w``~'~'
Robeht Doyle, Captain
Indio S.tati.on Commander.
CB: RD: g.t