HomeMy WebLinkAbout4.4 - 2824 Speed Limit change on Golden Gate Drive
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STAFF REPORT
CITY COUNCIL
DATE: October 15, 2019
TO: Honorable Mayor and City Councilmembers
FROM:
Christopher L. Foss, City Manager
SUBJECT:
Reducing the Speed Limit on Golden Gate Drive to 25 MPH
Prepared by: Sai Midididdi, Associate Civil Engineer (Traffic)
EXECUTIVE SUMMARY:
The City Council will consider introducing an ordinance to reduce the speed limit from
thirty miles per hour (30 mph) to twenty-five miles per hour (25 mph) on Golden Gate
Drive.
STAFF RECOMMENDATION:
Waive the Reading and Introduce an Ordinance Amending the Dublin Traffic Code to
Reduce the Speed Limit on Golden Gate Drive.
FINANCIAL IMPACT:
The cost to modify the existing speed limit signs can be accommodated in the Fiscal
Year 2019-2020 Street Maintenance Operating Budget.
DESCRIPTION:
The California Vehicle Code Section 40802 specifies that engineering and traffic
surveys (E&TS) must be conducted every seven years for certain types of roadways
and that appropriate police officer training be completed to allow speed limit
enforcement by use of radar. The existing speed limit of thirty miles per hour (30 mph)
on Golden Gate Drive (Attachment 2) was established several years ago by Ordinance
5-85 (Attachment 3). Since that time significant changes have occurred along Golden
Gate Drive including the construction of mixed -use residential developments,
commercial developments, and various roadway improvements.
Procedure for Establishing Speed Limit
The E&TS determines the operative criterion called "85th percentile" or "critical" speed.
The "85th percentile" speed is considered as the target speed at or below which 85% of
drivers are traveling in free-flowing conditions. Speed limits are to be set at the nearest
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five mile per hour (5 mph) increment to the cri tical speed. The second part of the E&TS
includes an analysis of the roadway to determine whether there are any offsetting
factors such as residential density, pedestrian and bicycle features, intersecting
driveways, accident history, schools, and so forth, which would cause the
recommended speed limit to be further reduced by five miles per hour (5 mph).
Study Findings
The E&TS study is included with this staff report (Attachments 4). Golden Gate Drive is
in the Downtown Dublin Transit Oriented District. It is located in a redeveloped area that
has mixed-use residential, retail, and, commercial developments along its frontage,
such as Aster Apartments, Valor Crossing, and Connolly Station. Golden Gate Drive
consists of two travel lanes (one each way), se parated by center medians, with
additional turn lanes at intersections. The roadway is flat and straight. There are striped
bicycle lanes and on-street parking areas. The West Dublin/Pleasanton BART station is
located at the south end of the street and generates vehicle trips and pedestrian/bicycle
trips throughout the day.
The E&TS indicates that the critical speed is twenty-eight miles per hour (28 mph),
which suggests the posted speed limit of thirty miles per hour (30 mph), by rounding to
the nearest 5 mph increment. However, given the primarily residential character of the
roadway and the proximity to West Dublin/Pleasanton BART station, with associated
bicycle and pedestrian traffic, the E&TS recommends that the posted speed limit be
established at twenty-five miles per hour (25 mph) by applying the optional five mile per
hour (5 mph) reduction in speed limit.
Based on the findings in the E&TS, Staff recommends that City Council introduce an
ordinance to reduce the speed limit on Golden Gate Drive to twenty-five miles per hour
(25 mph).
STRATEGIC PLAN INITIATIVE:
None.
NOTICING REQUIREMENTS/PUBLIC OUTREACH:
None.
ATTACHMENTS:
1. Ordinance Amending Dublin Traffic Code to Reduce Speed Limit on Golden Gate
Drive
2. Location Map
3. Ordinance 05-85
4. Engineering and Traffic Survey Report - Golden Gate Drive
ORDINANCE NO. __– 19
AN ORDINANCE OF THE CITY COUNCIL
OF THE CITY OF DUBLIN
* * * * * * * * *
AM ENDING DUBLIN TRAFFIC CODE TO REDUCE SPEED LIMIT ON GOLDEN GATE DRIVE
The City Council of the City of Dublin does hereby ordain as follows:
Section 1: The following language shall be removed from Section 6.60.020 of the City of Dublin
Traffic Code – Thirty Miles per Hour
“Golden Gate Drive: Dublin Boulevard to End of Street ”
Section 2: The following language shall be added to Section 6.60.010 of the City of Dublin
Traffic Code – Twenty-Five Miles per Hour
“Golden Gate Drive: Dublin Boulevard to End of Street ”
Section 3: Severability. The provisions of this Ordinance are severable and if any provision,
clause, sentence, word or part thereof is held illegal, invalid, unconstitutional, or inapplicable to
any person or circumstances, such illegality, invalidity, unconstitutionality, or inapplicability shall
not affect or impair any of the remaining provisions, clauses, sentences, sections, words or
parts thereof of the ordinance or their applicability to other persons or circumstances.
Section 4: Effective Date. This Ordinance shall take effect and be enforced thirty (30) days
following its adoption and following placement of speed limit signs providing notice thereof.
Section 5: Posting. The City Clerk of the City of Dublin shall cause this Ordinance to be posted
in at least three (3) public places in the City of Dublin in accordance with Section 36933 of the
Government Code of the State of California.
PASSED, APPROVED AND ADOPTED this 5th day of November 2019, by the following
vote:
AYES:
NOES:
ABSENT:
ABSTAIN:
_______________________________
Mayor
ATTEST:
___________________________________
City Clerk
Golden Gate Drive between Dublin Boulevard and End of Street
Golden Gate Drive N
h
ORDINANCE. NO 5 - $5
AN ORDINANCE OF THE CITY OF DUBLIN
ESTABLISHING TRAFFIC REGULATIONS
The City Council of the City of Dublin does ordain as follows:
Section 1. TWENTY-FIVE (25) MILES PER HOUR (MPH)
The declared speed limit for each of the following street segments
shall be established at 25 mph:
(a) Amador Valley Boulevard
200 feet east of Village Parkway to 200 feet west of
Stagecoach Road
(b) Amarillo Road
Ladera Drive to Shadow Drive
(c) Bandon Drive
Carlow Way to Kimball Avenue
(d) Bellina,Street
San Ramon Road to Galindo Drive
(e) Brighton Drive
Lucania Street to Callan Street
(f) Clark Avenue
Dublin Boulevard to Maple Drive
`Y (g) Davona Drive
Chatam to Village Parkway
(h) Davona Drive
Wicklow Lane to Alcosta Boulevard
(i) Donahue Drive
Amador Valley Boulevard to•Hillrose Drive
(j) Donlon Way
Dublin Boulevard to City Limit
(k) Dublin Court
Dublin Boulevard to End of Street
(1) Shannon Avenue
Peppertree Road to Vomac Road
(m) Sierra Court
Trinity Court to End of Street
(n) Silvergate Drive
Dublin Boulevard to Hansen Road
(o) Silvergate Drive
San Ramon Road to Castilian Road
(p) Southwick Drive
Bloomington Way to Northern City Limit
(q) Starward Drive
Amador Valley Boulevard to Oxbow Lane
(r) Tamarack Drive
Village Parkway to Alene Street
(s) Vomac Road
�:�' San Ramon Road to Landale Avenue
t' .' Z
t�
cl - 'car
ORDINANCE NO. 5 $5
,TABLISHING TRAFFIC REGULATIONS
-+age 2
(t) York Drive
Lancaster Road to King Way
Section 2.. THIRTY (30) MILES PER HOUR (MPH)
The declared speed limit for each of the following street segments
shall be established at 30 mph:
(a) Amador Plaza Road
Amador Valley Boulevard to End of Street
(b) Clark Avenue
Village Parkway to Dublin Boulevard
(c) Golden Gate Drive
Dublin Boulevard to End of Street
(d) Regional Street
Amador Valley Boulevard to End of Street
(e) Scarlett Court
Dougherty Road to End of Street
(f) Sierra .Court.
Dublin Boulevard to Trinity Court.
(g) Sierra Lane
Dougherty Road to Sierra Court
(h) Village Parkway
Amador Valley Boulevard to Clark Avenue
Section 3. THIRTY-FIVE (35) MILES' PER HOUR (MPH)
The declared speed limit for each of the following street segments
shall be established at 35 mph:
(a) Amador Valley Boulevard
San Ramon Road to 200 feet east of Village Parkway
(b) Amador Valley Boulevard
• 200 feet west of Stagecoach Road to DoughertyRoad
(c) Dougherty Road
Amador Valley Boulevard to Sierra Lane
(d) Dougherty Road
Sierra Lane to Southern City Limit
(e) Dublin Boulevard
Western City Limit to Dougherty Road
(g) Village Parkway
Kimball Avenue to Amador Valley Boulevard
ZD INANCE NO. 5 - 85
...ATABLISHING TRAFFIC REGULATIONS
ge 3
Section 4. FORTY (40) MILES PER HOUR (MPH)
The declared speed limit for each of the following street segments
shall be established at 40 mph:
(a) San Ramon Road
Alcosta Boulevard to Southern City Limit
Section 5. FORTY-FIVE (45) MILES PER HOUR (MPH)
The declared speed limit for each of the following streetsegments
shall be established at 45 mph
(a) Dougherty Road
Amador Valley Boulevard to Northern City Limit
Section 6 IMMEDIATE EFFECT
This Ordinance shall take effect immediately upon its enactment
---ecause the adoption and immediate effect thereof is necessary in order to
--otect vehicular and pedestrian safety.
Section 7. POSTING OF ORDINANCE
The City Clerk of the City of Dublin..shall cause this ordinance to be
posted in at least three (3) public places in the City of Dublin in
accordance with Section 36933 of the Government Code of the State of
California.
PASSED AND ADOPTED by the City Council of the City of Dublin on this
25thday of February 1985 by the following votes:
AYES: Couricilmembers Hegarty, Jeffery, Moffatt, -Vonheeder and
Mayor Snyder
NOES: None
ABSENT: None
Mayor
ATTES-r--
City Clerk
Dublin Speed Limits
Engineering & Traffic Survey
For
Golden Gate Drive
Prepared For:
The City of Dublin, CA
August, 2019
Prepared By:
GHD, Inc.
2300 Clayton Rd., Suite 920
Concord, CA 94520
Page 1
Dublin Speed Limits E&TS Report 11159184 / R2592TIA001
INTRODUCTION
The following report presents the findings of an “Engineering and Traffic Speed Survey” to establish
a speed limit for the following street in the City of Dublin, California:
Golden Gate Drive (between Dublin Blvd. and south end of road)
The recommended speed limit is based on survey data, including radar speed measurements, field
observations of street characteristics, and a review of the collision history. The speed survey
identified the “85th-percentile speed” (or “critical speed”), which is defined as the speed at which 85
percent of the drivers are traveling at or below. Speed limits are generally established by analysis of
the surveyed 85th-percentile speed in combination with the observed street characteristics.
Ultimately, the designation of safe and efficient speed limits should be based on sound engineering
judgment. Additional input from police personnel regarding the recommendations should also be
considered before speed limits are established.
DATA COLLECTION
The data collection included radar spee d surveys and identifying the roadway characteristics.1 The
roadway characteristics included alignment, street parking, adjacent land use, and level of side-
street activity. The speed surveys recorded 200 observations, which meets or exceeds the
CaMUTCD recommended guidelines.
The collision history was identified over a three year period (6/1/16-5/31/19). A collision rate,
expressed in terms of the number of collisions per million vehicle miles of travel, was calculated and
compared to the statewide average rates for similar streets.2
An Engineering & Traffic Survey worksheet was completed for the roadway. The E&TS worksheet
contains information that includes posted speed limit, measured critical speed, roadway
characteristics, collision rates, and the survey recommendations. A supplementary E&TS worksheet
providing further detail regarding conditions that may not be readily apparent to a driver is also
included.
RESULTS/RECOMMENDATIONS
The existing posted speed limit for Golden Gate Drive is 30 mp h. Based on the collected data and
roadway characteristics, it is recommended that a new speed limit be established at 25 mph. The
survey findings are identified in the Engineering and Traffic Survey worksheets which are attached
along with the speed summary worksheet.
References
1. GHD Inc., Radar Speed Surveys conducted February 7, 2019.
2. California Department of Transportation, 2014 Collision Data on California State Highways, Business,
Transportation, and Housing Agency, Division of Traffic Operations, Sacramento, CA.
August, 2019
Dublin Speed Limits E&TS Report 11159184 / R2592TIA002
Golden Gate Drive (between Dublin Blvd. and south end of road)
Golden Gate Drive is oriented in a north-south direction and extends from Dublin Boulevard to the
end of the roadway approximately 600 feet south of St. Patrick Way. It consists of two lanes (one
each way), separated by center medians, with additional turn lanes at intersections. The segment is
flat and straight. There are striped bicycle lanes and shoulder/parking areas. The intersection at St.
Patrick Way has all-way stop sign control, which creates two relatively short roadway sections
between controlled intersections. Street parking is allowed in some locations and there is high
parking demand. The road is classified as a collector street in the City of Dublin Street Functional
Classification System. It is located in a redeveloped area consisting of multi-family residential units
and retail/commercial businesses located on both sides of the street. The West Dublin/Pleasanton
BART station is located at the south end of the road, which generates v ehicle trips and
pedestrian/bicycle trips throughout the day. There is a crosswalk with RRFB (flashing beacon) lights
located near the south end of the road that provides pedestrian access to the BART station.
Speed Data
The segment has a posted speed limit of 30 mph. There is a southbound 30 mph speed limit sign
and a “30” pavement legend located south of Dublin Boulevard. There are no northbound speed
limit signs on the segment. The measured 85th-percentile speed was recorded as follows:
Speed 85th % Recommended
Golden Gate Drive: Limit Speed Speed Limit
Dublin Blvd. to south end of road 30 mph 28.0 mph 25 mph (New)
`
Recommendation
Based on the measured 85th-percentile speed and existing street characteristics, it is recommended
that a new speed limit be established at 25 mph. Factors include new res idential development and
roadway improvements, including striped bicycle lanes and parking lanes, vehicles moving in and
out of on-street spaces, and increased pedestrian and bicycle activity associated with the adjacent
residential units and the BART station located at the south end of the road. Therefore it is
recommended that an optional 5 mph reduction from the nearest rounded 85 th-percentile speed of
30 mph be implemented, resulting in a new speed limit of 25 mph.
Improvements
Install 25 mph speed limit signs (with or without accompanying “25” pavement legends).
CITY OF DUBLIN
SPEED LIMIT
ENGINEERING / TRAFFIC SURVEY
Street: Golden Gate Drive Limits: between Dublin Blvd. and south end of road
Length (feet): 1,200’
SPEEDS
Location of Survey: Dublin Blvd. to end of road
250’ s/o St. Patrick Wy.
Date Taken: 2/7/19
Posted Speed: 30 mph
Pace Speed: 20-29 mph
% in Pace, Above, Below 86; 7; 7
Critical Speed (85%) 28.0 mph
Range of Speeds 17-34 mph
ROADWAY DESIGN AND TRAFFIC CHARACTERISTICS
Width (ft.): 46’-64’ No. Lanes: 2 (1 NB & 1 SB) Classification: Collector
Average Daily Traffic: 5,475 Date Taken: May 2019
Special Conditions (Parking, Roadway Alignment, Land Use, School Area, etc.): flat and
straight; striped bicycle lanes and shoulders; parking allowed in some areas; adjacent properties
consist of residential and commercial/retail; also the West Dublin/Pleasanton BART station with
parking garage at south end of road. Adjacent land uses generate pedestrian and bicycle
activity along the segment.
ACCIDENT CHARACTERISTICS
Accident Period Analyzed: 6/1/16 – 5/31/19
Number of Accidents (List Total and Each Year): 1 (’16-17 = 0, ’17-18 = 1, ’18-19 = 0)
Number of Speed Related Accidents (Total and Each Year): 0 (16-17 = 0, 17-18 = 0, 18-19 = 0)
Calculated Accident Rate: 1.38 acc./m.v.m. Statewide Average Rate: 2.21 acc./m.v.m.
SURVEY RESULTS
Recommendations: Based on the measured critical speed
and roadway characteristics, which include new residential
development, bicycle lanes, on-street parking with high
demand; and a BART station; with associated vehicle,
pedestrian, and bicycle activity, it is recommended that an
optional 5 mph downward speed zoning be applied to the
nearest rounded 85th % speed of 30 mph, resulting in a
25 mph speed limit (New).
Study Prepared By: GHD Inc.
Date: August 26, 2019
Approved By: Date
Mr. Obaid Khan, P.E.
Transportation and Operations Manager
City of Dublin, CA
Approved Speed Limit: 25 mph
Per CVC 40803, Survey Expires:
CITY OF DUBLIN
SUPPLEMENTAL HIGHWAY, TRAFFIC, AND ROADSIDE CONDITIONS
ENGINEERING / TRAFFIC SURVEY
Street: Golden Gate Drive Limits: between Dublin Blvd. and south end of road
CONDITIONS NOT NECESSARILY APPARENT TO DRIVER & PEDESTRIAN/BICYCLIST SAFETY
ADJACENT LAND USE
Yes
Pre-School/Nursery/Daycare
Elementary School
Middle School
High School
Senior Center / Facility
Hospital / Medical Office
X Retail/Commercial Activity
Recreation: Park/Playground/Sports Field
X Other Adjacent multi-family residential buildings. Also West Dublin BART station with
parking garage and pedestrian access.
ROADWAY CHARACTERISTICS
Yes
__ Roadway Horizontal Alignment Change
__ Roadway Vertical Alignment Change
Narrow Lanes (< 12 feet wide)
X Bicycle Lanes and/or Bicycle Activity
Designated Safe-Route-to-School
Designated Truck Route
X Designated Bus Route
X Other Pedestrian and bicycle activity associated with residential and BART land uses.
PARKING & SIDE STREET CHARACTERISTICS
Yes
X On-Street Parking Allowed High street parking demand.
Parking Occupancy X High __ Medium Low
Parking Turnover _ High X_ Medium Low
X Commercial Driveway Activity High X Medium _ Low
_ Direct Residential Driveway Access / Vehicles Turning In & Backing Out
Street: Golden Gate Drive Limits: between Dublin Blvd. and south end of road
DENSITY OF RESIDENTIAL UNITS
Do any of the following characteristics apply?
Yes
_ (A) Upon one side of the highway, within a distance of a quarter mile, the
contiguous property fronting thereon is occupied by 13 or more separate
dwelling houses or business structures. Or
_ (B) Upon both sides of the highway, collectively, within a distance of a
quarter of a mile, the contiguous property fronting thereon is occupied by
16 or more separate dwelling houses or business structures. Or
The portion of highway is longer than one-quarter of a mile, but has the
ratio of separate dwelling houses or business structures to the length
of the highway described in either subparagraph (A) or (B).
RECOMMENDED SPEED LIMIT
Based on the surveyed speed data and roadway characteristics in accordance with the
guidelines for establishing speed limits as outlined in the California Manual on Uniform Traffic
Control Devices (2014 Edition, Revision 3, Chapter 2B), application of a 5 mph reduction from
the nearest rounded 85th percentile speed of 30 mph for roadside conditions not readily
apparent to a driver is appropriate. Therefore the recommended speed limit is: 25 mph
Per CVC 40803, Survey Expires:
Approved By:
Mr. Obaid Khan, P.E.
Transportation and Operations Manager
City of Dublin, CA
Authorized Signature:
Date:
RADAR SPEED SURVEY SUMMARY
Road:Golden Gate Drive Date:2/7/19
Location:between Dublin Blvd. and South end of road Time:2:15 - 4:45 pm
Dublin, CA Weather:Clear
Speed Limit:30 mph
No. of Surveys =200 No. of Surveys =100 No. of Surveys =100
Average Speed =24.6 Average Speed =24.4 Average Speed =24.8
50th Percentile =25.0 50th Percentile =24.5 50th Percentile =25.0
85th Percentile =28.0 85th Percentile =28.0 85th Percentile =28.0
90th Percentile =29.0 90th Percentile =29.0 90th Percentile =29.0
95th Percentile =30.0 95th Percentile =29.1 95th Percentile =30.0
Pace Speed =20-29 Pace Speed =20-29 Pace Speed =20-29
# In Pace, Above, Below = 172, 13, 15 # In Pace, Above, Below = 85, 5, 10 # In Pace, Above, Below = 87, 8, 5
% In Pace, Above, Below = 86, 7, 7 % In Pace, Above, Below = 85, 5, 10 % In Pace, Above, Below = 87, 8, 5
Sample Variance =11.82 Sample Variance =12.64 Sample Variance =11.01
Stndrd. Deviation =3.44 Stndrd. Deviation =3.56 Stndrd. Deviation =3.32
Range 1*S =0.67 Range 1*S =0.62 Range 1*S =0.69
Range 2*S =0.97 Range 2*S =0.96 Range 2*S =0.96
Range 3*S =1.00 Range 3*S =1.00 Range 3*S =1.00
GHD Inc.
0
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11
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1
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0 5 10 15
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# vehiclesmphNorthbound Speeds
0
0
0
0
0
2
3
6
6
8
12
10
11
9
10
9
6
4
2
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
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0
0
0
0
0
0
0
0
0
0
0
0
0
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0 5 10 15
13
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# vehiclesmphSouthbound Speeds
0
0
0
0
2
5
8
13
12
15
23
19
20
19
20
18
13
7
2
2
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
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0
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0 5 10 15 20 25
13
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# vehiclesmphBoth Direction Speeds