HomeMy WebLinkAbout4.8 - 3354 Speed Limit Change on Dublin Boulevard
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STAFF REPORT
CITY COUNCIL
DATE: September 1, 2020
TO: Honorable Mayor and City Councilmembers
FROM:
Linda Smith, City Manager
SUBJECT:
Second Reading of Ordinance Reducing the Speed Limit on Dublin
Boulevard between Scarlett Drive and Tassajara Road to 40 MPH
Prepared by: Sai Midididdi, Associate Civil Engineer (Traffic)
EXECUTIVE SUMMARY:
The City Council will consider adopting an ordinance to reduce the speed limit from 45
miles per hour to 40 miles per hour on Dublin Boulevard between Scarlett Drive and
Tassajara Road. The first reading of this ordinance was held at the August 18, 2020,
Regular City Council Meeting.
STAFF RECOMMENDATION:
Waive the reading and adopt the Ordinance Amending the Dublin Traffic Code to
Reduce the Speed Limit on Dublin Boulevard between Scarlett Drive and Tassajara
Road.
FINANCIAL IMPACT:
The cost to modify the existing speed limit signs can be accommodated in the Fiscal
Year 2020-2021 Street Maintenance Budget.
DESCRIPTION:
On August 18, 2020, the City Council waived the reading and introduced an Ordinance
to amend the Dublin Traffic Code to reduce the speed limit on Dublin Boulevard
between Scarlett Drive and Tassajara Road from 45 miles per hour to 40 miles per
hour. The Ordinance is now ready for adoption.
The new speed limits will go into effect 30 days following adoption of the ordinance
once signs are posted to give notice thereof.
STRATEGIC PLAN INITIATIVE:
None.
Page 2 of 2
NOTICING REQUIREMENTS/PUBLIC OUTREACH:
None.
ATTACHMENTS:
1. Ordinance Amending Dublin Traffic Code to Reduce Speed Limit on Dublin
Boulevard between Scarlett Drive and Tassajara Road
2. Engineering and Traffic Survey Report - Dublin Boulevard
3. August 18, 2020 City Council Staff Report (without attachments)
ORDINANCE NO. __– 20
AN ORDINANCE OF THE CITY COUNCIL
OF THE CITY OF DUBLIN
* * * * * * * * *
AMENDING DUBLIN TRAFFIC CODE TO REDUCE SPEED LIMIT ON DUBLIN BOULEVARD
BETWEEN SCARLETT DRIVE AND TASSAJARA ROAD
The City Council of the City of Dublin does hereby ordain as follows:
Section 1: The following language shall be removed from Section 6.60.050 of the City of Dublin
Traffic Code – Forty-Five Miles per Hour
“Dublin Boulevard: Southern Pacific Railroad Right of Way to Hacienda Drive”
Section 2: The following language shall be modified in Section 6.60.050 of the City of Dublin
Traffic Code – Forty-Five Miles per Hour
from
“Dublin Boulevard: Hacienda Drive to Fallon Road”
to
“Dublin Boulevard: Tassajara Road to Fallon Road”
Section 3: The following language shall be added to Section 6.60.040 of the City of Dublin
Traffic Code – Forty Miles per Hour
“Dublin Boulevard: Scarlett Drive to Tassajara Road”
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 1st day of September 2020, by the following
vote:
AYES:
NOES:
ABSENT:
ABSTAIN:
_______________________________
Mayor
ATTEST:
___________________________________
City Clerk
May 2020
Dublin Speed Limits E&TS Report 11159184 0501 / R2592TIA003
Dublin Boulevard (between Scarlett Dr. and Hacienda Dr.)
This segment of Dublin Boulevard extends in an east -west direction between Scarlett Drive and
Hacienda Drive. It consists of six through lanes (three each way) with additional turn lanes at
intersections. The segment is mostly flat and straight, but there is a modest S -curve in the middle of
the segment. The travel directions are separated by center medians and there are strip ed bicycle
lanes and parking is not allowed. It is classified as a principal arterial street in the City of Dublin
Street Functional Classification System. It is also a designated Truck Route (Dublin Boulevard is a
designated Truck Route between San Ramo n Road and Fallon Road). The Dublin Boulevard
corridor is continuing to develop with newer commercial and residential properties generating
vehicle trips throughout the corridor. Newly developed properties are located along both sides of the
street, including multi-family residential units and a retail shopping center near Hacienda Drive. The
East Dublin/Pleasanton BART station is located south of Dublin Boulevard near Arnold Road.
There are driveways along the segment with vehicles turning in and out of parking lots. The Iron
Horse Trail intersects Dublin Boule vard at Scarlett Drive, providing trail access to the East
Dublin/Pleasanton BART station , and a Class l trail extends along the north side of Dublin
Boulevard. Pedestrian and bicycle trips are g enerated by the adjacent retail, residential, BART
station, and Class l trails. This segment of Dublin Boulevard carries freeway cut-through trips
diverting from I-580, which tends to travel at higher speeds, and the segment also experiences
stopped traffic and vehicle queues on the approaches to intersections .
Speed Data
There is an existing posted speed limit of 45 mph. There are eastbound speed limit signs located
east of Scarlett Drive and Iron Horse Parkway. There are westbound signs west of Hacienda Drive,
Iron Horse Parkway, and Sterling Street. (The speed limit decreases to 35 mph west of Scarlett
Drive.) The measured 85th-percentile speed was recorded as follows:
Speed 85th % Recommended
Dublin Boulevard: Limit Speed Speed Limit
Scarlett Dr. to Hacienda Dr. 45 mph 44.0 mph 40 mph (NEW )
Recommendation
Based on the measured 85 th-percentile speed and existing street characteristics, it is recommended
that a new speed limit of 40 mph be established. Factors include continued development of
residential and commercial properties with associated traffic along the Dublin Boulevard corridor;
vehicles turning in and out of driveways along the segment; nearby residential units, BART Statio n,
and Class l trail, with pedestrian/bicycle street-crossings; and variable traffic conditions ranging from
higher-speed cut-through traffic to stopped/queued traffic at intersection approaches. Therefore, it is
recommended that an optional 5 mph reduction from the nearest rounded 85th-percentile speed of
45 mph be implemented, resulting in a new 40 mph speed limit (change from existing 45 mph
speed limit).
Improvements
Replace existing 45 mph speed limit signs with new 40 mph speed limit signs (type R 2-1 per
CaMUTCD).
CITY OF DUBLIN
SPEED LIMIT
ENGINEERING / TRAFFIC SURVEY
Street: Dublin Boulevard Limits: between Scarlett Dr. and Hacienda Dr.
Length (feet): 4,800’ / 0.91 mi
SPEEDS
Location of Survey: Scarlett Dr. to Hacienda Dr.
700’ w/o Scarlett Dr.
Date Taken: 11/5/19
Posted Speed: 45 mph
Pace Speed: 35-44 mph
% in Pace, Above, Below 77; 13; 10
Critical Speed (85%) 44.0 mph
Range of Speeds 28-51 mph
ROADWAY DESIGN AND TRAFFIC CHARACTERISTICS
Width (ft.): 94’-140’ No. Lanes: 6 (3 WB & 3 EB) Classification: Principal Arterial
Average Daily Traffic: 20,800 Date Taken: March 2017
Special Conditions (Parking, Roadway Alignment, Land Use, School Area, etc.): mostly straight
with moderate S-curve in middle of segment; striped bicycle lanes; parking not allowed;
continuing development of residential and commercial uses along Dublin Boulevard corridor;
vehicles turning in and out of driveways; nearby BART station, Iron Horse Trail crossing and
Class l trail on Dublin Boulevard; pedestrian/bicycle activity; variable traffic conditions on Dublin
Boulevard including higher-speed cut-through traffic from the freeway, as well as stopped
traffic and queued vehicles on approaches to intersections.
ACCIDENT CHARACTERISTICS
Accident Period Analyzed: 1/1/17 – 12/31/19
Number of Accidents (List Total and Each Year): 9 (’17 = 2, ‘18 = 3, ‘19 = 4)
Number of Speed Related Accidents (Total and Each Year): 8 (‘17 = 2, ‘18 = 2, ‘19 = 4)
Calculated Accident Rate: 0.43 acc./m.v.m. Statewide Average Rate: 1.25 acc./m.v.m.
SURVEY RESULTS
Recommendations: Based on the measured critical speed and
roadway characteristics, including ongoing commercial and
residential development; traffic turning in & out of driveways;
pedestrian, bicycle, & trail activity; and variable traffic conditions,
it is recommended that an optional 5 mph downward speed
zoning be applied to the nearest rounded 85th % speed of
45 mph, establishing a 40 mph speed limit (New).
Study Prepared By: GHD Inc.
Date: May 22, 2020
Approved By: Date
Ms. Sai Midididdi, T.E.
Associate Civil Engineer (Traffic)
City of Dublin, CA
Approved Speed Limit: 40 mph
Per CVC 40803, Survey Expires:
CITY OF DUBLIN
SUPPLEMENTAL HIGHWAY, TRAFFIC, AND ROADSIDE CONDITIONS
ENGINEERING / TRAFFIC SURVEY
Street: Dublin Boulevard Limits: between Scarlett Dr. and Hacienda Dr.
CONDITIONS NOT NECESSARILY APPARENT TO DRIVER & PEDESTRIAN/BICYCLIST SAFETY
ADJACENT LAND USE
Marked ‘X’ if 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 Multi-family Residential Units
Iron Horse Trail crossing and Class l trail
ROADW AY CHARACTERISTICS
X 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
X Designated Truck Route
X Designated Bus Route
X Other Variable traffic conditions, ranging from freeway cut-through traffic at excessive speeds
to slowed/stopped conditions with queued vehicles on approaches to intersections.
PARKING & SIDE STREET CHARACTERISTICS
_ On-Street Parking Allowed
Parking Occupancy High _ Medium Low
Parking Turnover High _ Medium Low
X Commercial Driveways. Activity: X High _ Medium Low
X Residential Units/Neighborhoods Located on Side-Streets
Direct Residential Driveway Access With Vehicles Turning In & Backing Out
Street: Dublin Boulevard Limits: between Scarlett Dr. and Hacienda Dr.
DENSITY OF RESIDENTIAL UNITS
Do any of the following characteristics apply?
Marked ‘X’ if 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 45 mph for roadside conditions not readily
apparent to a driver is appropriate. Therefore the recommended speed limit is: 40 mph (New)
Per CVC 40803, Survey Expires:
Approved By:
Ms. Sai Midididdi, T.E.
Associate Civil Engineer (Traffic)
City of Dublin, CA
Authorized Signature:
Date:
RADAR SPEED SURVEY SUMMARY
Road:Dublin Boulevard Date:11/5/19
Location:between Scarlett Dr. and Hacienda Dr.Time:12:35 - 1:30 pm
Dublin, CA Weather:Clear
Speed Limit:45 mph
No. of Surveys =200 No. of Surveys =100 No. of Surveys =100
Average Speed =39.5 Average Speed =38.7 Average Speed =40.3
50th Percentile =39.0 50th Percentile =38.0 50th Percentile =40.0
85th Percentile =44.0 85th Percentile =43.2 85th Percentile =45.0
90th Percentile =45.0 90th Percentile =44.1 90th Percentile =46.0
95th Percentile =47.0 95th Percentile =46.1 95th Percentile =47.0
Pace Speed =35-44 Pace Speed =35-44 Pace Speed =35-44
# In Pace, Above, Below = 153, 26, 21 # In Pace, Above, Below = 77, 10, 13 # In Pace, Above, Below = 76, 16, 8
% In Pace, Above, Below = 77, 13, 10 % In Pace, Above, Below = 77, 10, 13 % In Pace, Above, Below = 76, 16, 8
Sample Variance =19.50 Sample Variance =19.08 Sample Variance =18.80
Stndrd. Deviation =4.42 Stndrd. Deviation =4.37 Stndrd. Deviation =4.34
Range 1*S =0.625 Range 1*S =0.72 Range 1*S =0.7
Range 2*S =0.955 Range 2*S =0.96 Range 2*S =0.93
Range 3*S =1.00 Range 3*S =1.00 Range 3*S =1.00
GHD Inc.
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
3
5
1
2
11
5
13
10
7
11
5
6
4
5
3
2
3
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 5 10 15
13
14
15
16
17
18
19
20
21
22
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31
32
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48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
# vehiclesmphEastbound Speeds
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
2
3
6
5
6
9
10
9
8
9
8
6
5
4
3
0
1
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 5 10 15
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
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48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
# vehiclesmphWestbound Speeds
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
2
1
4
5
3
5
17
10
19
19
17
20
13
15
12
11
8
6
6
1
1
3
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 5 10 15 20 25
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
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37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
# vehiclesmphBoth Direction Speeds
May 2020
Dublin Speed Limits E&TS Report 11159184 0501 / R2592TIA003
Dublin Boulevard (between Hacienda Dr. and Tassajara Rd.)
This segment of Dublin Boulevard extends in an east -west direction between Hacienda Drive and
Tassajara Road. There are six through lanes (three each way) with additional turn l anes at
intersections. The segment is mostly flat and straight with a modest S-curve in the middle of the
segment. The travel directions are separated by center medians and there are striped bicycle lanes .
Parking is not allowed. It is classified as a principal arterial street in the City of Dublin Street
Functional Classification System. It is also a designated Truck Route (Dublin Boulevard is a
designated Truck Route between San Ramon Road and Fallon Road ). The Dublin Boulevard
corridor is continuing to develop with newer commercial and residential properties generating
vehicle trips throughout the corridor. This segment extends through a commercial/retail area with
vehicles turning in and out of parking lots. There are also residential units on the north side (no
direct access) and a large office complex on the south side near Tassajara Road. P edestrian and
bicycle trips are generated by the retail, residential, and office uses, and there is a Class l trail along
the north side of Dublin Boulevard between Hacienda Drive and the Tassajara Creek Trail system .
Dublin Boulevard experiences varying traffic flow conditions, including freeway cut -through traffic
diverting from I-580 which tends to travel faster than the environment allows, as well as stopped
traffic and vehicle queues on the approaches to intersections.
Speed Data
There is an existing posted speed limit of 45 mph. There is an eastbound speed limit sign located
east of Hacienda Drive and a westbound sign west of Tassajara Road. The measured 85th-
percentile speed was recorded as follows:
Speed 85th % Recommended
Dublin Boulevard: Limit Speed Speed Limit
Hacienda Dr. to Tassajara Rd. 45 mph 45.0 mph 40 mph (NEW )
Recommendation
Based on the measured 85th-percentile speed and existing street characteristics, it is recommended
that a new speed limit of 40 mph be established. Factors include continued development of
residential and commercial properties with associated traffic along the Dublin Bo ulevard corridor;
vehicles turning in and out of driveways along the segment; nearby residential units and Class l trail
with pedestrian/bicycle street-crossings; and variable traffic conditions ranging from higher -speed
cut-through traffic to stopped/queued traffic at intersection approaches. Therefore, it is
recommended that an optional 5 mph reduction from the nearest rounded 85 th-percentile speed of
45 mph be implemented, resulting in a new 40 mph speed limit (change from existing 45 mph
speed limit).
Improvements
Replace existing 45 mph speed limit signs with new 40 mph speed limit signs (type R 2-1 per
CaMUTCD).
CITY OF DUBLIN
SPEED LIMIT
ENGINEERING / TRAFFIC SURVEY
Street: Dublin Boulevard Limits: between Hacienda Dr. and Tassajara Rd.
Length (feet): 4,600’ / 0.87 mi
SPEEDS
Location of Survey: Hacienda Dr. to Tassajara Rd.
400’ e/o Hawk Wy.
Date Taken: 11/5/19
Posted Speed: 45 mph
Pace Speed: 35-44 mph
% in Pace, Above, Below 75; 16; 9
Critical Speed (85%) 45.0 mph
Range of Speeds 29-52 mph
ROADWAY DESIGN AND TRAFFIC CHARACTERISTICS
Width (ft.): 112’-148’ No. Lanes: 6 (3 WB & 3 EB) Classification: Principal Arterial
Average Daily Traffic: 21,428 Date Taken: November 2019
Special Conditions (Parking, Roadway Alignment, Land Use, School Area, etc.): mostly straight
with broad S-curve in middle of segment; striped bicycle lanes; parking not allowed; continuing
development of residential and commercial uses along Dublin Boulevard corridor; ve hicles
turning in and out of driveways; Class l trail on north side from Hacienda Drive to Tassajara
Creek Trail system; pedestrian/bicycle activity; variable traffic conditions on Dublin Boulevard
with mix of higher speed freeway cut-through traffic and stopped and queued vehicles on
approaches to intersections.
ACCIDENT CHARACTERISTICS
Accident Period Analyzed: 1/1/17 – 12/31/19
Number of Accidents (List Total and Each Year): 20 (’17 = 9, ‘18 = 5, ‘19 = 6)
Number of Speed Related Accidents (Total and Each Year): 10 (‘17 = 6, ‘18 = 1, ‘19 = 3)
Calculated Accident Rate: 0.98 acc./m.v.m. Statewide Average Rate: 1.25 acc./m.v.m.
SURVEY RESULTS
Recommendations: Based on the measured critical speed and
roadway characteristics, including ongoing commercial and
residential development; traffic turning in and out of driveways;
pedestrian, bicycle, & trail activity; and variable traffic conditions,
it is recommended that an optional 5 mph downward speed
zoning be applied to the nearest rounded 85th % speed of
45 mph, establishing a 40 mph speed limit (New).
Study Prepared By: GHD Inc.
Date: May 22, 2020
Approved By: Date
Ms. Sai Midididdi, T.E.
Associate Civil Engineer (Traffic)
City of Dublin, CA
Approved Speed Limit: 40 mph
Per CVC 40803, Survey Expires:
CITY OF DUBLIN
SUPPLEMENTAL HIGHWAY, TRAFFIC, AND ROADSIDE CONDITIONS
ENGINEERING / TRAFFIC SURVEY
Street: Dublin Boulevard Limits: between Hacienda Dr. and Tassajara Rd.
CONDITIONS NOT NECESSARILY APPARENT TO DRIVER & PEDESTRIAN/BI CYCLIST SAFETY
ADJACENT LAND USE
Marked ‘X’ if 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 Multi-family Residential Units
Class l trail
ROADWAY CHARACTERISTICS
X 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
X Designated Truck Route
X Designated Bus Route
X Other Variable traffic conditions, ranging from freeway cut-through traffic at excessive speeds
to slowed/stopped conditions with queued vehicles on approaches to intersections.
PARKING & SIDE STREET CHARACTERISTICS
_ On-Street Parking Allowed
Parking Occupancy High _ Medium Low
Parking Turnover High _ Medium Low
X Commercial Driveways. Activity: X High _ Medium Low
X Residential Units/Neighborhoods Located on Side-Streets
Direct Residential Driveway Access With Vehicles Turning In & Backing Out
Street: Dublin Boulevard Limits: between Hacienda Dr. and Tassajara Rd.
DENSITY OF RESIDENTIAL UNITS
Do any of the following characteristics apply?
Marked ‘X’ if 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 45 mph for roadside conditions not readily
apparent to a driver is appropriate. Therefore the recommended speed limit is: 40 mph (New)
Per CVC 40803, Survey Expires:
Approved By:
Ms. Sai Midididdi, T.E.
Associate Civil Engineer (Traffic)
City of Dublin, CA
Authorized Signature:
Date:
RADAR SPEED SURVEY SUMMARY
Road:Dublin Boulevard Date:11/5/19
Location:between Hacienda Dr. and Tassajara Rd.Time:2:00 - 3:05 pm
Dublin, CA Weather:Clear
Speed Limit:45 mph
No. of Surveys =200 No. of Surveys =100 No. of Surveys =100
Average Speed =40.4 Average Speed =39.9 Average Speed =40.9
50th Percentile =40.0 50th Percentile =40.0 50th Percentile =41.0
85th Percentile =45.0 85th Percentile =44.2 85th Percentile =45.0
90th Percentile =47.0 90th Percentile =47.0 90th Percentile =46.1
95th Percentile =48.0 95th Percentile =48.1 95th Percentile =48.0
Pace Speed =35-44 Pace Speed =34-43 Pace Speed =36-45
# In Pace, Above, Below = 149, 33, 18 # In Pace, Above, Below = 70, 18, 12 # In Pace, Above, Below = 77, 13, 10
% In Pace, Above, Below = 75, 16, 9 % In Pace, Above, Below = 70, 18, 12 % In Pace, Above, Below = 77, 13, 10
Sample Variance =19.87 Sample Variance =21.51 Sample Variance =17.98
Stndrd. Deviation =4.46 Stndrd. Deviation =4.64 Stndrd. Deviation =4.24
Range 1*S =0.71 Range 1*S =0.70 Range 1*S =0.73
Range 2*S =0.94 Range 2*S =0.95 Range 2*S =0.95
Range 3*S =1.00 Range 3*S =1.00 Range 3*S =1.00
GHD Inc.
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
3
1
0
4
5
7
7
10
8
12
8
8
7
3
2
2
2
4
2
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 5 10 15
13
14
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16
17
18
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49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
# vehiclesmphEastbound Speeds
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
5
2
4
8
8
6
11
9
12
7
7
5
3
4
2
1
0
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 5 10 15
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
# vehiclesmphWestbound Speeds
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
4
2
1
9
7
11
15
18
14
23
17
20
14
10
7
5
6
6
3
2
3
1
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# vehiclesmphBoth Direction Speeds
Page 1 of 3
STAFF REPORT
CITY COUNCIL
DATE: August 18, 2020
TO: Honorable Mayor and City Councilmembers
FROM:
Linda Smith, City Manager
SUBJECT:
Reducing the Speed Limit on Dublin Boulevard between Scarlett Drive and
Tassajara Road to 40 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
45 miles per hour to 40 miles per hour on Dublin Boulevard between Scarlett Drive and
Tassajara Road.
STAFF RECOMMENDATION:
Waive the reading and INTRODUCE the Ordinance Amending the Dublin Traffic Code
to Reduce the Speed Limit on Dublin Boulevard between Scarlett Drive and Tassajara
Road.
FINANCIAL IMPACT:
The cost to modify the existing speed limit signs can be accommodated in the Fiscal
Year 2020-2021 Street Maintenance Budget.
DESCRIPTION:
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 45 miles per hour on Dublin Boulevard between
Scarlett Drive and Tassajara Road was established several years ago by Ordinance 8-
94 and Ordinance 19-02. Since that time, significant changes have occurred along the
subject segment of Dublin Boulevard including construction of mixed-use, residential,
retail, and commercial developments, and the completion of various roadway
improvements.
Procedure for Establishing Speed Limit
The E&TS (Attachment 2) determines the operative criterion called "85th percentile" or
"critical" speed. The "85th percentile" speed is considered 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 five mile per hour (5 mph) increment to the critical speed. The E&TS also
Page 2 of 3
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, and location of schools, which would cause the
recommended speed limit to be further reduced by five miles per hour.
Engineering and Traffic Survey (ET&S) Findings
Dublin Boulevard between Scarlett Drive and Tassajara Road is classified as a principal
arterial street in the City of Dublin Street Functional Classification System. It consists of
six through lanes (three each way separated by medians), striped bicycle lanes, and
additional turn lanes at intersections. The roadway is mostly flat and straight with a
modest S-curve in the middle of the segment.
This Dublin Boulevard corridor is continuing to develop with new residential, retail and
commercial properties along its frontage. Multi-family residential units, high and medium
density residential apartments, condominiums, townhomes, retail shopping centers and
large office complexes are located along both sides of the street. A future 30-acre
community park will be located on the northeast side of Dublin Boulevard and Scarlett
Drive intersection. The Dublin/Pleasanton BART Station is located south of Dublin
Boulevard, adjacent to the I-580 freeway between DeMarcus Boulevard and Campus
Drive. There are driveways along the segment with vehicles turning in and out of
parking lots. The Iron Horse Regional Trail intersects Dublin Boulevard at Scarlett Drive,
providing trail access to the Dublin/Pleasanton BART Station. In addition, there is a
Class I trail along the north side of Dublin Boulevard between Hacienda Drive and
Tassajara Creek Trail. This segment of Dublin Boulevard also experiences varying
traffic flow conditions including freeway cut-through trips diverting from I-580.
The E&TS indicates that the critical speed is 44 miles per hour on Dublin Boulevard
between Scarlett Drive and Hacienda Drive and 45 miles per hour between Hacienda
Drive and Tassajara Road. This suggests a posted speed limit of 45 miles per, by
rounding to the nearest five mile-per-hour increment. However, given the recent
development activities along the corridor, proximity to Dublin/Pleasanton BART station,
and Class l trails with associated bicycle and pedestrian traffic, the E&TS recommends
that the posted speed limit be established at 40 miles per hour by applying the optional
five mile per hour 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 Dublin Boulevard between Scarlett Drive and
Tassajara Road to 40 miles per hour.
STRATEGIC PLAN INITIATIVE:
None.
NOTICING REQUIREMENTS/PUBLIC OUTREACH:
None.
ATTACHMENTS:
1. Ordinance Amending Dublin Traffic Code to Reduce Speed Limit on Dublin
Boulevard between Scarlett Drive and Tassajara Road
Page 3 of 3
2. Engineering and Traffic Survey Report - Dublin Boulevard