TRAFFIC & TRANSPORTATION COMMISSION AGENDA REPORT AGENDA ITEM #3 T/T MTG: 072815 DATE: JULY 28, 2015 TO: TRAFFIC & TRANSPORTATION COMMISSION FROM: BENJAMIN CHAN, P.E, T.E., DEPUTY PUBLIC WORKS DIRECTOR ROBERT YALDA, P. E., T. E., PUBLIC WORKS DIRECTOR / CITY ENGINEER SUBJECT: 2015 CITYWIDE SPEED SURVEY BACKGROUND: Speed surveys serve as a valuable information source in determining safe and reasonable speeds for local roads. Speed surveys not only compile data of the speed of vehicles on the road, but also take into account the volume of traffic on the road and the collision rates. A citywide speed survey is intended to serve as the basis for the establishment and enforcement of speed limits for selected streets within the City. The Citywide Speed Survey was conducted by National Data Base (NDS), using calibrated handheld radar speed guns. The survey has been completed and is ready for review by the Traffic & Transportation Commission. A citywide speed survey is referred to as an Engineering and Traffic Survey (E&TS) in Section 627 of the 2015 State of California Vehicle Code (CVC). The following excerpt from the CVC defines speed surveys and specifies their purpose and applications.
Engineering and Traffic Survey CVC Section 627 (a) "Engineering and Traffic Survey," as used in this code, means a survey of highway and traffic conditions in accordance with methods determined by the Department of Transportation for use by state and local authorities. (b) An engineering and traffic survey shall include, among other requirements deemed necessary by the department, consideration of all of the following: (1) Prevailing speeds as determined by traffic engineering measurements. (2) Collision records. (3) Highway, traffic, and roadside conditions not readily apparent to the driver. (c) When conducting an engineering and traffic survey, local authorities, in addition to the factors set forth in paragraphs (1) to (3), inclusive, of subdivision (b) may consider all of the following: (1) Residential density, if any of the following conditions exist on the particular portion of highway and the property contiguous thereto, other than a business district: (A) Upon one side of the highway, within a distance of a quarter of a mile, the contiguous property fronting thereon is occupied by 13 or more separate dwelling houses or business structures. (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. (C) 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). (2) Pedestrian and bicyclist safety. Citywide speed surveys serve another function. In order for law enforcement to use speed detection devices, such as speed radar, a current speed survey must be updated to reflect current conditions of the roadway. This ET&S must be updated every seven years in order to continue the use of radar speed enforcement (CVC Section 40802(c)(2)(B)(i). The speed survey presented here will serve to update the information concerning the streets of Calabasas, and allow law enforcement to use all of the tools available 2
to them to enforce speed limits. DISCUSSION: Prima Facie, Local Streets and Business Districts The California Speed Law provides blanket prima facie speed limit of 25 mph within residence districts and business districts (CVC 515 and 235). In addition, the prima facie speed of 25 mph also applies when approaching or passing a school building or when passing a senior center or other facility primarily used by senior citizens. The California Vehicle Code also states that the law does not require posting these streets with a prima facie 25 mph limit because the aforementioned characteristics of a residence district or business district are readily apparent to a motorist. Therefore, a prima facie 25 mph speed limit can be enforced with radar units. However, CVC Section 22357 permits the establishment of speed limits greater than 25 mph upon the basis that an ET&S that has a speed greater than 25 miles per hour would facilitate the orderly movement of vehicular traffic and would be reasonable and safe. The local authority may, by ordinance, determine and declare a prima facie speed limit in the range between 30 to 60 miles per hour or a maximum speed limit of 65 miles per hour, whichever is found most appropriate to facilitate the orderly movement of traffic and is reasonable and safe. Existing Guidelines for Posting Speed Limits California State Law requires that the posting of speed limits be based on the 85 th percentile of travel speeds for any street. The 85 th percentile speed is defined as the speed at which 85% of the traffic is traveling at or below that said speed. Experience has shown that the 85 th percentile speed is characteristic to safe and reliable driving and generally presents a reasonable speed limit. In general, speed limits are set in increments of 5 mph. Speed limits that are set 10 miles or more below the 85 th percentile will tend to make a large number of drivers operate their vehicles at a speed above the set limit. For practical purposes and to conform to the 5 mph increment, the numerical speed limit is usually at the 5 mph increment directly above or below the 85 th percentile speed. This numerical value is a realistic and enforceable speed limit that allows law enforcement agencies to issue citations to reckless and/or unreliable drivers 3
who do not conform to what the majority (85%) of drivers find to be reasonable speed. The posted speed may be reduced by 5 mph from the nearest 5 mph increment of the 85th-percentile speed, in compliance with CVC Sections 627 and 22358.5. Any adjustments beyond the additional 5 mph reduction are much more difficult to defend and may not be acceptable in the court of law. For cases in which the nearest 5 mph increment of the 85th-percentile speed would require a rounding up, then the speed limit may be rounded down to the nearest 5 mph increment below the 85th percentile speed, in compliance with CVC Section 21400 (b). Physical conditions such as width, curvature, grade and surface conditions, or any other condition readily apparent to the driver, in the absence of other factors, would not require special downward speed zoning. Analysis and Review of City Streets The majority of the speed limits within the City will not change. However, based upon the recent speed survey, there are three street segments where speed limits will decrease. They are identified and highlighted in Attachment B. The following is a brief summary for the street segments where a change is recommended in the posted speed limit: Park Sorrento/Civic Center Way- between Parkway Calabasas and Calabasas Rd Existing 30 mph: The findings of the speed survey show that the 85th percentile speed is 28 mph. The nearest five mph increment of the 85th percentile speed would be rounded up to 30 mph. Taking into consideration the recent restriping of parking layout from angle to perpendicular parking on Civic Center Way, between Park Sorrento and Calabasas Rd and the presence of pedestrians crossing Civic Center Way near the Commons, it is recommended that the proposed speed limit on Park Sorrento/Civic Center Way between Parkway Calabasas and Calabasas Rd be lowered to 25 mph from the current posted speed of 30 mph. Mureau Rd between Las Virgenes Rd and Los Angeles County Boundary Line Existing 45 mph: The findings of the speed survey show that the 85 th percentile speed is 42 mph. The nearest five mph increment of the 85 th percentile speed would be rounded down to 40 mph. Taking into consideration the numerous driveways within this segment of the roadway, it is recommended that the proposed speed limit on Mureau Rd between Las Virgenes Rd and Los Angeles County Boundary Line be lowered to 40 mph from the current posted speed of 45 mph. 4
Calabasas Rd between Mureau Rd and Civic Center Way Existing 45 mph: The findings of the speed survey show that the 85th percentile speed is 42 mph. The nearest five mph increment of the 85th percentile speed would be rounded down to 40 mph. Taking into consideration the numerous driveways within this segment of the roadway and the presence of delivery trucks unloading cars to several dealerships west of Parkway Calabasas, it is recommended that the proposed speed limit on Calabasas Rd between Mureau Rd and Civic Center Way be lowered to 40 mph from the current posted speed of 45 mph. REQUESTED ACTION It is requested that the Traffic & Transportation Commission: 1. Provide input and comments regarding the Citywide Speed Survey. 2. Recommend the new Citywide Speed Survey to the Calabasas City Council. ATTACHMENTS: Attachment A: Applicable California Vehicle Code Sections, 2015 Edition Attachment B: Citywide Speed Survey Attachment C: Color-Keyed Map of Speed Limits 5