HomeMy WebLinkAbout2022-08-18; Traffic and Mobility Commission; ; Revise Prima Facie Speed Limits for Gateway Road between El Camino Real and El Fuerte Street and Cadencia Street from Del Rey Avenue to 0.15 mile north of Piragua StreetMeeting Date: Aug. 18, 2022
To: Traffic and Mobility Commission
Staff Contact: Miriam Jim, Senior Engineer
Miriam.Jim@carlsbadca.gov, 442-339-5796
John Kim, City Traffic Engineer
John.Kim@carlsbadca.gov, 442-339-2757
Subject: Revise Prima Facie Speed Limits for Gateway Road between El Camino Real
and El Fuerte Street and Cadencia Street from Del Rey Avenue to 0.15 mile
north of Piragua Street
Recommended Action
Support staff’s recommendation to City Council to revise prima facie speed limits on:
1)Gateway Road between El Camino Real and El Fuerte Street, from 40 miles per hour to 35
miles per hour
2)Cadencia Street from Del Rey Avenue to 0.15 mile north of Piragua Street, from 40 miles
per hour to 35 miles per hour
Background
Setting speed limits requires a rational and defensible procedure to maintain the public’s
confidence in public agency traffic and legal systems. By following a uniform procedure, public
agencies can establish uniform speed limits throughout the state that avoid influence from
political pressure or emotional perceptions. The California State Legislature establishes
authority for California speed limits through the California Vehicle Code, or CVC. The CVC
describes speed limit authority in language used primarily for enforcement purposes. The
California Department of Transportation, or Caltrans, publishes the California Manual for
Setting Speed Limits that establishes the standard procedure for setting legally defensible
speed limits. This manual provides guidance on how speed limits may be established in
compliance with the CVC and how appropriate signage may be installed according to the
California Manual on Uniform Traffic Control Devices, or CAMUTCD.
Speed limit determinations rely on the premise that a reasonable speed limit is one that
conforms to the actual behavior of the majority of drivers. Speed limits are normally set near
the 85th percentile speed. The 85th percentile speed, also known as the “critical speed”, is the
speed at or below which 85% of the traffic is moving, and statistically represents one standard
deviation above the average speed. According to the California Manual for Setting Speed Limits,
Aug. 18, 2022 Item #3 1
Federal Highway Administration studies have demonstrated that the most effective attribute in
establishing the speed limit is to determine the 85th percentile speed and set the posted speed
limit close to that value. The empirical data in these studies demonstrates that setting the
speed limit too high or too low can increase collisions.
In addition, setting the speed limit arbitrarily low often results in a disproportionate number of
drivers who become violators of the speed limit, which does not facilitate the orderly
movement of traffic and requires constant enforcement to maintain compliance. With this in
mind, speed limits that are set near the 85th percentile speed are safer and produce less
variance in vehicle speeds. Therefore, the 85th percentile speed is used to establish the upper
limit of operating speeds that are considered reasonable and prudent.
CVC Section 22352 sets two prima facie speed limits in California, 15 miles per hour, or mph,
and 25 mph. These limits cover six specific classes of location. No Engineering and Traffic
Survey, or E&TS, or speed limit signs are required for these classes of location. These six classes
of location are as follow:
• Uncontrolled railroad crossings (15 mph)
• Blind, uncontrolled intersections (15 mph)
• Alleyways (15 mph)
• Locations that meet business and residential district requirements (25 mph)
• School zones (25 mph)
• Areas immediately around senior centers (25 mph)
For locations that do not meet the six classes listed above, CVC Section 22358 allows local
jurisdictions to establish speed limits on roadways based on the findings of an E&TS. An E&TS is
a survey that consists of engineering measurements of the 85th percentile speed, a review of
the collision history and a review of roadway conditions. The CAMUTCD provides detailed
guidelines and procedures on conducting an E&TS in compliance with CVC Section 627.
A comprehensive review of the collision history of the roadway is an important element in the
process to establish a speed limit on that roadway. A collision review reveals whether a high
incidence of speed-related collisions exists on the roadway at specific locations. If no significant
collision history exists, public agencies may conclude that most drivers operate their vehicles in
a prudent manner, which supports using the 85th percentile speed to establish the speed limit.
CVC Section 22358.5 specifically prohibits lowering the speed limit for conditions that are
readily apparent to drivers, such as roadway width, curvature, grade and surface conditions.
Conditions that are not readily apparent to drivers may be used to lower the speed limit up to
an additional 5 mph in certain cases, but those speed limits are sometimes defeated in court.
For unusual conditions, or conditions not readily apparent to drivers, appropriate warning
devices should be considered in lieu of lowering the speed limit.
Aug. 18, 2022 Item #3 2
Since roadway conditions are integral to the appropriate setting of speed limits, changes to
roadway conditions can create opportunities to re-evaluate existing speed zones and
recommend changes, if appropriate.
Discussion
Gateway Road between El Camino Real and El Fuerte Street
Gateway Road between El Camino Real and El Fuerte Street is classified as a
Local/Neighborhood Street in the Mobility Element of the General Plan. This segment of
Gateway Road features one travel lane and one bike lane in each direction. A contiguous
sidewalk is provided on both sides of the roadway. The road has a curb-to-curb width of 52
feet. It follows a curvilinear alignment with roadway grades that vary from 1% to 6%. Adjacent
land uses include light industrial, single- and multi-family residential and two local shopping
centers.
Gateway Road is currently posted at 40 mph based on the E&TS dated Nov. 20, 2015, which
showed the 85th percentile speed to be 43 mph.
In 2019, two sets of chicanes, approximately 300’ long each, were installed on Gateway Road
between Alicante Road and Innovation Way, as well as between Innovation Way and Village
Green Drive, as a traffic calming measure to address speeding concerns from residents. A
marked crosswalk with pedestrian-activated Rectangular Rapid Flashing Beacons, or RRFBs, was
installed at the west leg of the intersection at Innovation Way. This crosswalk was installed in
2020 as part of the off-site improvements by the mixed-used development located at the
northeast quadrant of the intersection of Gateway Road and Innovation Way. There is another
raised and marked crosswalk with RRFBs located 630’ east of El Camino Real. Based on these
changes to the roadway, staff conducted the appropriate studies to re-evaluate the existing 40
mph speed zone on Gateway Road.
Staff reviewed the Police Department traffic collision summary report for a two-year period
from April 1, 2020 through March 31, 2022 for this segment of Gateway Road. There were two
reported collisions, one of which was speed-related. None of the collisions involved pedestrians
or bicyclists.
A speed survey was conducted on Gateway Road on June 16, 2021. The 85th percentile speed of
36 mph was calculated based on a sample of 100 vehicles (50 vehicles in each direction of
travel). The 85th percentile speeds from previous speed surveys and this recent survey are
summarized in Table 1.
Based on the foregoing CVC-related authority, and the findings of the recently performed E&TS,
a staff recommends postinga speed limit of 35 mph for Gateway Road between El Camino Real
and El Fuerte Street.
Aug. 18, 2022 Item #3 3
Table 1 – Speed Survey Data
Survey Date
Existing 85th
Percentile
Speed (mph)
Existing
Speed Limit
(mph)
Survey Date
New 85th
Percentile
Speed (mph)
Proposed
Posted
Speed Limit
(mph)
9/11/2014 43 40 6/16/2021 36 35
Cadencia Street from Del Rey Avenue to 0.15 mile north of Piragua Street
Cadencia Street from Del Rey Avenue to 0.15 mile north of Piragua Street is classified as a
Local/Neighborhood Street in the Mobility Element of the General Plan. This segment of
Cadencia Street has one travel lane in each direction. Sidewalk is provided on each side of the
road except for a 600-feet portion on the west side of the road north of Pirague Street where
sidewalk is not constructed. The road has a curb-to-curb width of 40 feet. It follows a curvilinear
alignment with roadway grades that vary from 1.5% to 13.7%. Adjacent land uses include
single- and multi-family residential and open space.
This segment of Cadencia Street is currently posted at 40 mph based on the E&TS dated Oct.
22, 2014, which showed the 85th percentile speed of 41 mph.
A recent traffic calming project, approved by the Traffic and Mobility Commission at its Aug. 3,
2020 meeting, installed three radar speed feedback signs on Cadencia Street (two in
southbound and one in the northbound direction) and a marked crosswalk with RRFBs on the
north side of the intersection at Venado Street. Construction of the project was completed in
Winter 2021. Based on these changes to the roadway, staff conducted the appropriate studies
to re-evaluate the existing 40 mph speed zone on Cadencia Street.
Staff reviewed the Police Department traffic collision summary report for a two-year period
from May 1, 2020, through April 30, 2022 for this segment of Cadencia Street. There was one
collision that was not speed-related and did not involve pedestrians or bicyclists.
A speed survey was conducted on this segment of Cadencia Street on May 19, 2022. The 85th
percentile speed of 37 mph was calculated based on a sample of 100 vehicles (50 vehicles in
each direction of travel). The 85th percentile speeds from previous speed surveys and this
recent survey are summarized in Table 2.
Based on the foregoing CVC-related authority, and the findings of the recently performed E&TS,
staff recommend posting a speed limit of 35 mph for Cadencia Street from Del Rey Avenue to
0.15 mile north of Piragua Street.
Aug. 18, 2022 Item #3 4
Table 2 – Speed Survey Data
Survey Date
Existing 85th
Percentile
Speed (mph)
Existing
Speed Limit
(mph)
Survey Date
New 85th
Percentile
Speed (mph)
Proposed
Posted
Speed Limit
(mph)
3/9/2015 41 40 5/19/2022 37 35
Necessary City Council Action
The City Council must adopt an ordinance to establish the new prima facie speed limits on:
1) Gateway Road between El Camino Real and El Fuerte Street as 35 mph; and
2) Cadencia Street from Del Rey Avenue to 0.15 mile north of Piragua Street as 35 mph.
Next Steps
Upon receiving support from the Traffic and Mobility Commission, staff will introduce an
ordinance for City Council adoption. Once the ordinance is adopted, appropriate regulatory
speed limit signs will be posted in compliance with the CAMUTCD. Once the signs are installed,
the Police Department can enforce the new speed limits on these two roadway segments.
Exhibits
1. Location Map
2. Engineering and Traffic Survey (Gateway Road)
3. Engineering and Traffic Survey (Cadencia Street)
Aug. 18, 2022 Item #3 5
1
LOCATION MAP
Aug. 18, 2022 Item #3 6
CITY OF CARLSBAD ENGINEERING AND TRAFFIC SURVEY
STREET: Gateway Road
LIMITS: El Camino Real to El Fuerte Street
FACTORS A. Prevailing Speed Data: Direction: Eastbound/Westbound
Date of Speed Survey Location of Speed Survey 85th Percentile 10 MPH Pace Percent in Pace
6/16/21 300 Feet w/o Village Green Drive 36 MPH 27 to 37 MPH 85 B. Accident History: (4/01/20 through 3/31/22) Speed-Related Accidents Pedestrian and/or Bicycle Accidents Total Accidents
1 None 2
C. Traffic Factors: Average Daily Traffic Traffic Controls Pedestrian/Bicycle Traffic Bicycle Lanes On-Street Parking
5,373 – West of Innovation Way (2016)
Traffic Signals at El Fuerte Street, Finnila Place and El Camino Real Light Bicycle Lane on Each Side Parking Prohibited on Each Side D. Roadway Factors: Street Classification Length of Segment Roadway Width Number of Lanes Vertical Alignment Horizontal Alignment Sidewalks Driveways Street Lighting
Circulation Element – Unclassified. Mobility Element – Local/Neighborhood Street. 0.83 Mi. 52 Feet (Curb-to-Curb) One Lane Each Direction Roadway Grades Vary from 1.00% to 5.89% Curvilinear Sidewalk on Each Side Five Driveways Street Lights on Each Side E. Special Conditions: Travel lanes are separated by either a painted median, two-way left-turn lane, or chicanes. F. Adjacent Land Uses: Light Industrial, Single-Family Residential, Multi-Family Residential, Two Local Shopping Centers including Several Restaurants. G. Remarks/Conditions Not Readily Apparent: Marked crosswalks with Rectangular Rapid Flashing Beacons (RRFBs) are located on the west side of the intersection at Innovation Way and also 630 feet east of El Camino Real. The latter crosswalk is a raised crosswalk. Chicanes are located both east and west of Innovation Way. Warning signs for the chicanes and RRFBs are posted for each direction of travel. H. Traffic Engineer's Recommendation (Explanation): This speed zone satisfies the conditions of Section 627 of the California Vehicle Code and has been prepared and evaluated in accordance with the California Manual on Uniform Traffic Control Devices, effective March 30, 2021, with respect to design and prevailing speeds, accident records, pedestrian and bicyclist safety, intersection and driveway spacing, and roadside and traffic conditions not readily apparent to the driver. A speed limit posting of 35 MPH is found to be appropriate and justified. I. Approvals: Recertification of existing speed zone per Sections 22357, 22358 and 40802 of the California Vehicle Code. Establishment of new speed zone. Approved________________________________________________ John T. Kim Date City Traffic Engineer CA RCE 56667
NOTE: Appropriate speed survey is attached hereto and made a part hereof.
Exhibit 2
Aug. 18, 2022 Item #3 7
CITY OF CARLSBAD ENGINEERING AND TRAFFIC SURVEY
STREET: Cadencia Street
LIMITS: Del Rey Avenue to 0.15 Mile north of Piragua Street
FACTORS
A.Prevailing Speed Data:Direction: Northbound/Southbound
5/19/22 At Venado Street 37 MPH 28 to 38 MPH 74%
Date of Speed SurveyLocation of Speed Survey85th Percentile10 MPH PacePercent in Pace
B.Accident History:(5/01/20 through 4/30/22)
Speed-Related AccidentsPedestrian and/or Bicyclist AccidentsTotal Accidents
None None 1
C. Traffic Factors:
Average Daily TrafficPedestrian/Bicycle TrafficBicycle LanesOn-Street Parking
1,257 – n/o Piragua Street (2016); 2,360 – n/o Del Rey Avenue (2016) Light No Designated Bicycle Lanes Have Been Striped on the Roadway Parking Allowed on Each Side except n/o Piragua Street Where 383 Feet of Parking is Prohibited on Each Side
D.Roadway Factors:
Street ClassificationLength of SegmentRoadway WidthNumber of LanesVertical AlignmentHorizontal AlignmentSidewalksDrivewaysStreet Lighting
Circulation Element – Unclassified. Mobility Element – Local/Neighborhood Street 0.43 Mi. 40 Feet (Curb-to-Curb) 1 Lane Each Direction Roadway Grades Vary from 1.5% to 13.7% Curvilinear 600 Feet of Sidewalk Not Constructed on West Side North of Piragua Street Residential Driveways on East Side Limited Street Lighting E.Special Conditions: School bus stop located 400 feet north of Del Rey Avenue. A marked crosswalk with Rectangular RapidFlashing Beacons (RRFBs) is located on the north side of the intersection at Venado Street. Warning signs for the crosswalk andRRFBs are posted for each direction of travel. Three speed feedback signs, one northbound and two southbound, inform motorists ofthe speed they are traveling. Speed cushions are located at the south end of the subject roadway segment just north of Del ReyAvenue where a 25 mph speed zone begins.
F.Adjacent Land Uses: Single and Multi-Family Residential, Open Space
G.Remarks/Conditions Not Readily Apparent: The school bus stop may result in children crossing the roadway.
H.Traffic Engineer's Recommendation (Explanation): This speed zone satisfies the conditions of Section 627 of the CaliforniaVehicle Code and has been prepared and evaluated in accordance with the California Manual on Uniform Traffic Control Devices,effective March 30, 2021, with respect to design and prevailing speeds, accident records, pedestrian and bicyclist safety,intersection and driveway spacing, and roadside and traffic conditions not readily apparent to the driver. A speed limit posting of35 MPH is found to be appropriate and justified.
I.Approvals:
Recertification of existing speed zone per Sections 22357, 22358 and 40802 of the California Vehicle Code.Establishment of new speed zone.
Approved________________________________________________ John T. Kim Date City Traffic Engineer CA RCE 56667
NOTE: Appropriate speed survey is attached hereto and made a part hereof.
Exhibit 3
Aug. 18, 2022 Item #3 8
Miriam Jim, Senior Engineer, City of Carlsbad
John Kim, City Traffic Engineer, City of Carlsbad
August 18, 2022
Revise Prima Facie Speed Limits on portions
of Gateway Road and Cadencia Street
RECOMMENDED ACTION
Support staff’s recommendation to City Council to
revise prima facie speed limits on:
1.Gateway Rd between El Camino Real and El Fuerte St,
from 40 mph to 35 mph
2.Cadencia St from Del Rey Ave to 0.15 mile north of
Piragua St, from 40 mph to 35 mph
ITEM 3
BACKGROUND
•California Vehicle Code
–Describes laws regarding speed limits
•California Manual for Setting Speed Limits
–Establishes the standard procedure for setting legally defensible speed limits
•California Manual on Uniform Traffic Control Devices
–Provides guidance on appropriate signage
–Provides detailed guidelines and procedures on conducting an
Engineering and Traffic Survey
ITEM 3
BACKGROUND
•Reasonable speed limit is one that conforms to the actual behavior
of the majority of drivers
•FHWA studies support setting posted speed limit close to the
85th percentile speed
•Setting speed limit too high or too low can increase collisions
ITEM 3
ITEM 3
STREETS WITH SET PRIMA FACIE SPEED LIMITS
PER California Vehicle Code Section 22352
•Uncontrolled railroad crossings (15 mph)
•Blind, uncontrolled intersections (15 mph)
•Alleyways (15 mph)
•Business and residential district (25 mph)
•School Zones (25 mph)
•Areas immediately around senior centers (25 mph)
SPEED LIMIT ON OTHER STREETS
•An Engineering and Traffic Survey (E&TS) is required
–Engineering measurements of the 85th percentile speed
–Review of collision history
–Review of roadway conditions
ITEM 3
GATEWAY ROAD
BETWEEN EL CAMINO REAL AND EL FUERTE ST
ITEM 3
•Local/Neighborhood Street in the Mobility Element
•One vehicular lane and one bike lane in each direction
•Adjacent land uses include light industrial, single-and
multi-family residential and two local shopping centers
•Existing speed limit is 40 mph
GATEWAY ROAD ITEM 3
•In 2018, a raised
crosswalk with Rectangular Rapid
Flashing Beacons
(RRFBs) was installed between
El Camino Real and Campbell Place
GATEWAY ROAD ITEM 3
•In 2019, two sets of
chicanes were
installed east and
west of Innovation
Way intersection
GATEWAY ROAD ITEM 3
•In 2020, a marked
crosswalk with
RRFBs was installed
at Innovation Way
intersection
ITEM 3
Legend
Gateway Rd
Segment
Chicane
CrosswalkInnovation Way
GATEWAY ROAD SPEED LIMIT
ITEM 3
•Prior critical speed: 43 mph (40 mph speed limit)
•New critical speed: 36 mph
•Only one speed-related collision in 2-yr period
•Recommended speed limit: 35 mph
CADENCIA STREET
DEL RAY AVE TO 0.15 MILE N. OF PIRAGUA ST
ITEM 3
•Local/Neighborhood Street in the Mobility Element
•One vehicular lane in each direction
•Adjacent land uses include single-and multi-family
residential
•Existing speed limit is 40 mph
CADENCIA STREET ITEM 3
•In 2021, three radar
speed feedback
signs were installed
CADENCIA STREET ITEM 3
•In 2021, a marked
crosswalk with
RRFBs was installed
at Venado Street
ITEM 3
Legend
Cadencia St Segment
Speed Feedback Sign
Crosswalk
CADENCIA STEET SPEED LIMIT
ITEM 3
•Previous critical speed: 41 mph (40 mph speed limit)
•New critical speed: 37 mph
•No collision that was speed-related or involved
pedestrians or bicycles in 2-yr period
•Recommended speed limit: 35 mph
NEXT STEPS
•Upon receiving support from Traffic and
Mobility Commission, staff will introduce an
ordinance for City Council adoption
•After the ordinance is adopted, appropriate
speed limit signs will be posted
ITEM 3
RECOMMENDED ACTION
Support staff’s recommendation to City Council to
revise prima facie speed limits on:
1.Gateway Rd between El Camino Real and El Fuerte St,
from 40 mph to 35 mph
2.Cadencia St from Del Rey Ave to 0.15 mile north of
Piragua St, from 40 mph to 35 mph
ITEM 3
THANK YOU!
ITEM 3