CITY OF POWAY MEMORANDUM

Transcription

1 CITY OF POWAY MEMORANDUM TO: FROM: Traffic Safety Committee Steve Crosby P.E., City Engineer DATE: February 14, 2018 SUBJECT: Espola Road speeding concerns BACKGROUND In 2017, staff received a request from residents to consider the installation of permanent driver speed feedback signs on Espola Road between Sand Hill Road and Trailwind Road. The Sheriff s department has placed their mobile speed feedback trailer on this stretch of Espola Road at various times in response to resident concerns over drivers exceeding the speed limit. In order to evaluate the request for permanent speed feedback signs, traffic engineering staff conducted a field investigation of the subject area, researched collision histories, performed a radar speed survey on Espola Road, and reviewed how the current speed limit on Espola Road was established. FINDINGS Espola Road between Cloudcroft Drive and Titan Way is a four-lane arterial with a striped median. The Average Daily Traffic is 11,771 vehicles based on the 2013 Engineering and Traffic Survey (E&TS). The travel lanes vary in size but are at a minimum of twelve feet. There is a large horizontal curve that starts at Old Coach Road and terminates north of Country Day Road. Bike lanes are provided on both sides of the roadway. A sidewalk is provided on the North/East side and a dirt equestrian/pedestrian trail is provided on the South/West side of the street. There are a few residential driveways that take access from the south side of the street in the vicinity of Orchard Bend Road. Otherwise there is limited access along this stretch of roadway. The current posted speed limit on this stretch of road is 45 MPH. A review of the Transportation Injury Mapping System accident database found a total of ten accidents on this stretch of road from 2011 to One accident was determined to be related to unsafe speed. The other accidents were related to turns at the intersections, run off the road collisions with fixed objects or DUIs. The accident rate for this segment of roadway was 0.25 accidents per million vehicle miles compared to the Statewide average of 2.15 based on the findings from the 2013 E&TS.

2 Radar speed survey data was collected on November 28, 2017 on Espola Road north of Sandhill Road. The speed survey results are shown in Attachment A. It should be noted that the data has not been certified and therefore is not a valid speed survey for enforcement of the speed limit on this road. The data was only collected for informational purposes of this report. The posted speed limit on this segment of Espola Road is 45 MPH. The measured 50 th percentile Speed was 48 MPH and the 85 th percentile speed was 52 MPH in the southbound direction, and the measured 50 th percentile Speed was 48 MPH and the 85 th percentile speed was 53 MPH in the northbound direction. It should be noted that of the 224 vehicle speeds that were measured, 166 were measured travelling over the posted speed limit. Sections and of the California Vehicle Code (CVC) gives local municipalities the authority to set speed limits below the maximum speed limits set forth by State law, where such speed limits are supported by an E&TS. The E&TS enables our Sheriff s Deputies to use radar for traffic speed enforcement and serve as legal authority in accordance with the CVC. The City s current E&TS (Attachment B) adopted in 2013 was prepared pursuant to the guidelines of a previous edition of the California MUTCD. The MUTCD calls for speed limits to be established to the nearest 5 MPH increment of the 85 th percentile speed. For example, if the 85 th percentile speed is 47 MPH, the speed limit should be posted at 45 MPH. However, if the 85 th percentile speed is 48 MPH, the speed limit should be posted at 50 MPH. Section of the CVC gives local agencies the authority to lower the speed limit an additional 5 MPH below the adjusted 85 th percentile when there are conditions that are not apparent to drivers, which manifest in higher accident rates on the roadway. These include driveways directly abutting the roadway with frequent turns, insufficient sight distances, mid-block pedestrian and/or equestrian crossings, and pedestrians and bikers along the roadway. Roadway physical conditions, such as width, curvature, grade and surface conditions are not considered conditions not apparent to drivers by State law. Previously, the 5 MPH reduction rule under Section could be used if the speed limit was set to the nearest 5 MPH increment of the 85 th percentile speed. Now however, if the closest 5 MPH increment is also the lowest 5 MPH increment, the additional 5 MPH reduction cannot be used. For example, an 85 th percentile speed of 52 MPH would be rounded to 50 MPH and the additional 5 MPH reduction would not be allowed because 50 MPH is the nearest as well as the lowest 5 MPH increment. An 85 th percentile speed of 53 MPH would be rounded to 55 MPH, and with the 5 MPH reduction the speed limit could be reduced to 50 MPH if warranted by roadway conditions. Data from the 2013 E&TS shows an 85 th percentile speed of 48 MPH for Espola Road. Based on the California MUTCD and the latest Caltrans Traffic Operation Policy Directive #09-04, Change in current California MUTCD policy and procedure for setting speed limits in California, the speed limit on Espola Road would be set at 50 MPH, which is the nearest 5 MPH increment speed to the 85 th percentile speed of 48

3 MPH. However, staff at that time determined that the pedestrian/equestrian uses along the roadway justified use of the 5 MPH reduction rule in the posted speed, and staff recommended a 45 MPH speed limit for Espola Road along this segment. Based on the results of the recent uncertified speed survey data which indicated 85 th percentile speeds of 52 and 53 MPH, the posted speed limit would be set at 50 MPH. Staff would not be allowed to reduce the posted speed to 45 MPH based on the current criteria for use of the 5 MPH reduction rule. DISCUSSION Staff believes that there are four options for addressing vehicle speed on Espola Road. Increased Enforcement- The Sherriff s Department does cite vehicles along this stretch of Espola Road. The citations are valid based on the certified speed limit of 45 MPH that was completed with the 2013 E&TS. Increased enforcement combined with periodic deployment of the Sheriff s mobile speed feedback trailer is a viable option. Installation of permanent speed feedback signs- Permanent speed feedback signs have been installed in other areas of the City. Based on those installations, the anticipated cost would be $10,000 to $15,000 per installation for a pole mounted vehicle speed feedback sign in the shoulder of the road. However, Espola Road in this section is a wide four-lane facility with a striped median and a roadside shoulder installation may not be as effective as a mast arm installation extending over the travel lanes. Mast arm installation would significantly increase the cost per location. Staff has not determined the exact locations or type of speed feedback signs to provide the most benefit at reducing speeds on this segment of Espola Road. Increasing the Posted Speed- The 2013 ET&S findings reported an 85 th percentile speed of 48 MPH which would warrant a posted speed of 50 MPH. This was reduced to 45 MPH based on the 5 MPH increment reduction rule allowance. Changing the posted speed based on the recent speed survey conducted, which resulted in 85 th percentile speeds of 52 and 53 MPH, would result in a recommended posted speed of 50 MPH. Staff would not be allowed to reduce the posted speed to 45 MPH based on the current criteria for use of the 5 MPH reduction rule. The posted speed would have to be 50 MPH. This change would require following certain procedures including adoption by City Council in order for the new speed limit to be enforceable. Traffic Calming Through Striping Changes- Staff has restriped other roadway segments within the City in recent years to aid in the following: reducing driver speed due to driver perception of narrower lanes provide wider bike lanes provide bike lane buffers Bike lane buffers have been added to Scripps Poway Parkway, Pomerado Road, and most recently Poway road. The additional width required for the bike lane buffers was taken from the through travel lanes resulting in a narrowing of those lanes. The minimum lane widths have been held to eleven feet. For reference, Caltrans standard freeway lane width is twelve feet. The existing lanes on Espola Road currently vary to

4 more than thirteen feet in width. This section of Espola Road is scheduled to receive slurry seal in summer of This provides the opportunity to restripe the roadway starting with a clean slate. The road could be restriped with bike buffers and eleven foot maximum through lanes as shown in Attachment C. RECOMMENDATION Staff recommends that the Sheriff s Department increase enforcement in the area as resources are available. Staff also recommends restriping the road to install the bike lane buffers and narrow the travel lanes to eleven feet. After the restriping is implemented staff recommends conducting another radar speed survey to determine if the restriping was effective at lowering speed to be more in line with the current posted speed of 45 MPH. If speed survey result indicate that the restriping was ineffective at reducing speeds the permanent vehicle speed feedback sign option can be considered at that time. Attachments: A. Radar speed survey results B ET&S Espola Road speed survey section C. Proposed Espola Road Restriping

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11 Attachment C Espola Road Existing Condition 5' Bike Lane 13' 12' 15' Center Turn Lane 12' 13' 5' Bike Lane 75 Proposed Condition 6' Bike Lane 3' Buffer 11' 11' 13' Center Turn Lane 11' 11' 3' Buffer 6' Bike Lane 75 Espola Road between Cloudcroft Drive and Lake Poway Road Cross-Sections