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Home My WebLink About2008-10-06; Traffic Safety Commission; ; Establish a prima facie speed limit upon The Crossings Drive from Palomar Airport Road to its northerly terminus( ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ITEMNO. 6B LOCATION: INITIATED BY: The Crossings Drive, Palomar Airport Road to its northerly terminus City Engineer REQUESTED ACTION: Establish a prima facie speed limit upon The Crossings Drive from Palomar Airport Road to its norther_ly terminus. BACKGROUND: The Crossings Drive (formerly Hidden Valley Road) serves the LEGOLAND service entrance and is the only access to The Crossings at Carlsbad golf course. Although recently re-named, the street was constructed about 1997 when LEGOLAND was under construction. With the opening of The Crossings at Carlsbad golf course last year and the additional traffic volumes using the street, there is a need to establish a prima facie speed limit upon The Crossings Drive. SETTING SPEED LIMITS: Optimal mobility is enhanced and overall traffic flow improved when drivers are operating their vehicles at a speed that is reasonable, comfortable, convenient, and safe under the existing conditions. It is generally acknowledged that the control of speed can be a significant factor in influencing and improving roadway safety by reducing the number of collisions. In fact, the premise of CVC section 22350, Basic Speed Law, is that no person shall drive upon a road at a speed greater than is reasonable and prudent taking into account weather, visibility, and traffic on the road and in no event at a speed that endangers the safety of others. Driver behavior is an extension of social attitudes and most drivers operate their vehicles in a reasonable manner. This is demonstrated by their good driving records. Therefore, traffic laws established on the basis of the behavior of the reasonable and prudent motorist are found to be the most successful. As a result, speed limits that are considered credible and enforceable will help enhance traffic safety and the operating efficiency on the roadway and achieve driver compliance. Roads in Carlsbad are designed in accordance with engineering standards to satisfy the goals of having a safe roadway, provide mobility, offer mode choices, and to enhance efficient traffic flow. One way that these goals are achieved is by establishing proper and reasonable speed limits that can be enforced. Speed limits that are reasonable can help to achieve voluntary compliance by the majority of drivers without need for the presence of a police officer. Laws and/or the establishment of speed zones that arbitrarily restrict travel by the majority of motorists can lead to wholesale violations of the posted speed limit. For a speed limit to be considered effective, drivers must believe that the posted speed limit is safe, properly established, and legally enforceable. ( ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ( continued) ITEMNO. 6B In the City of Carlsbad, the predominant practice for managing speed is by legally establishing a prima facie speed limit and then posting the speed limit upon the road with regulatory signs. A prima facie speed limit recognizes that conditions change throughout the day and there is no one safe speed for all the conditions that may be present upon the roadway. Police enforcement is used to target the most egregious violators of the speed limit. A fundamental tenet is that laws are enacted to protect the majority of the public by regulating the unsafe or unreasonable actions of the few. When law enforcement officers and the courts have confidence that speed limits have been set on a reasonable basis, their enforcement efforts are more effective. Nationally recognized vetted practices and guidance per standards and procedures in the Federal Highway Administration's national Manual on Uniform Traffic Control Devices 2003 Edition are considered when setting speed limits. In California, this manual is titled the California Manual on Uniform Traffic Control Devices. The most common method of establishing speed limits incorporates traffic engineering principles and other factors, such as using the results of a speed survey, into the Traffic and Engineering Survey. Prima facie speed limits are established by law when the City Council adopts an ordinance and the speed limit is posted on the roadway to indicate the maximum reasonable speed for a driver to operate a vehicle under ideal conditions in off-peak free flowing conditions. Among many factors, the three most persuasive arguments to consider when setting a realistic, or rational, speed limit are: 1. Critical speed (85th percentile speed) 2. Collision history 3. Conditions that may not be readily apparent to the driver The premise implied in speed zoning is that the majority of drivers are operating their vehicles at or near the 85 th percentile speed. Drivers that operate their vehicle at speeds higher than the 85th percentile speed should be the focus of the police. An important speed zoning concept is that the disparity in speed between vehicles on the road is reduced when prima facie speed limits are established at or near the 85th percentile speed and, as a result, safety is enhanced. In addition, a speed limit that is established based upon the 85thpercentile speed will increase driver respect for the speed limit sign. Only those regulatory or warning signs that have the respect of the roadway user will have a positive effect to control driver behavior traffic. ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ( continued) ITEMNO. 6B A comprehensive review of the collision history on a roadway is an important element in the process to establish a speed limit. In the collision analysis, factors such as collision frequency, type, severity, road conditions, road geometry, lighting conditions, arid spatial distribution of the collisions are all considered. The review of collisions will also reveal if there is a high incidence of speed-related collisions on the road at specific locations. A number of collisions above the expected or normal threshold based upon Caltrans collision rates may be an indicator of a potential for reducing collisions. However, absent a significant collision history attributed to speed, it may be concluded that drivers are operating their vehicle in a reasonable and prudent manner at the speed they chose to drive. The installation of a speed limit sign will not automatically decrease accident rates nor increase roadway safety. Speed limits should not be lowered for conditions that are readily apparent to the driver and the speed limit signs are not used as intersection, curve or hazard warning devices. For the unusual conditions or conditions not readily apparent to motor vehicle operators, appropriate warning signs are installed, Design factors, including the geometric elements of the road, sight distance, or other factors such as adjacent land uses, parking, or pedestrian activity, may have a significant impact on the free flowing speed chosen by drivers. This driver chosen speed, in turn, is considered when establishing a prima facie speed limit. A number of factors may be considered when establishing a prima facie speed limit. The 2003 MUTCD lists such factors as: A. Road characteristics, shoulder condition, grade, alignment, and stopping sight distance; B. The pace speed; C. Roadside development and activity; and D. Reported crash experience for at least a 12-month period. Other factors are included, as appropriate, in the Engineering and Traffic Survey that becomes the basis .for establishing the prima facie speed limit. Among the requirements to be considered are residential density and pedestrian and bicycle safety. Other factors include superelevations, profile conditions, intersection spacing and offsets, commercial driveways, and pedestrians in the roadway where sidewalks do not exist. ( ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ( continued) ITEMNO. 6B Basic speed law as stipulated in the California Vehicle Code requires drivers to operate their vehicle at a speed that takes into account all roadway factors, environmental elements, adjacent land uses, and other traffic on the road. These are, in general, all readily apparent factors to the driver. Warning signs placed on the roadway can alert drivers to the presence of an unseen or unanticipated condition. As a result, drivers can operate their vehicle in a reasonable and prudent manner by adjusting speed for the condition that may be encountered. In summary, through the use of engineering, educational, and enforcement techniques, the management of vehicle speed is conducted. Voluntary public compliance with the posted speed limit is the goal when determining a realistic prima facie speed limit to post on a roadway. The realistic speed limit takes into consideration the normally competent and careful actions of a reasonable driver and provides for the regulation of unreasonable behavior by a few individuals. A posted speed limit should be readily accepted by drivers, be fair and reasonable, be related to risk on the roadway, be determined by the majority of drivers, and one that has a factual foundation. Posted speed limits reflect a balance of the various factors specific to the roadway. As a result, roadway safety can be improved and community concerns about traffic speed are appropriately and legally addressed. BASIS OF ACTION: The proposed speed limit for the road segment discussed in this report is regulated by section 22357(a) of the California Vehicle Code: "Whenever a local authority determines upon the basis of an engineering and traffic survey that a speed greater than 25 miles per hour would facilitate the orderly movement of vehicular traffic and would be reasonable and safe upon any street other than a state highway otherwise subject to a prima facie limit of 25 miles per hour, the local authority may by ordinance determine and declare a prima facie speed limit of 30, 35, 40, 45, 50, 55, or 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. The declared prima facie or maximum speed limit shall be effective when appropriate signs giving notice thereof are erected upon the street and shall not thereafter be revised except upon the basis of an engineering and traffic survey. This section does not apply to any 25 mile per hour prima facie limit which is applicable when passing a school building or the grounds thereof or when passing a senior center or other facility primarily used by senior citizens." ( ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ( continued) DATA: ITEMNO. 6B The Crossings Drive is a long cul-de-sac street that has a curb to curb width that varies between 40 feet and 64 feet. The street is unclassified in the Circulation Element of the General Plan. Concrete curb and gutter is installed on both sides of the street with concrete side walk installed along the west side and on the northerly 425 feet of the east side. Street lights are constructed on both sides of the street. Six driveways and one private street intersect The Crossings Drive. Vertical grades range from 4.54% to 10% and the street has a generally straight horizontal alignment. On-street parking prohibitions are established at various locations on both sides of the street. The land uses adjacent to the street are served by one traffic lane in each direction and lanes are separated by a yellow centerline stripe or a striped median. The Crossings Drive is controlled by a traffic signal at its intersection with Palomar Airport Road. A traffic count was obtained on The Crossings Drive on July 23, 2008. The two-way traffic volume was measured at 4,709 vehicles. The directional distribution of traffic volumes on The Crossings Drive is provided in Table A. DATE 7/23/08 TABLE A 24-HOUR TRAFFIC VOLUMES THE CROSSINGS DRIVE LOCATION NIB North of Palomar Airport Road 2,343 24-HOURADT •. SIB TOTAL 2,366 4,709 There has been one reported collision on The Crossings Drive for the two-year period ending July 31, 2008. However, this collision was not speed related. The absence of a significant collision history supports the recommended 40 mile per hour prima facie speed limit. ( ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: October 6, 2008 ( continued) ITEMNO. 6B Staff completed the Engineering and Traffic Survey (attached) for The Crossings Drive. The speed survey results contained within the Engineering and Traffic Survey are summarized in Table B. One speed survey was performed on August 26, 2008 in a location where prevailing speeds are representative of driver behavior in the proposed speed zone. TABLEB SPEED SURVEY DATA FOR CORTE DE LA VISTA <Sur-t~y · • i.Date 8/26/08 680' n/o Palomar Airport Road NB/SB .:,critical·' :,.<Pace' <'" t 'if~~f J .·t ~p:~ed ·, i>% in •Pace ' 42 33-43 79 The pace speed is the 10 mile per hour range of speeds that contain the highest number of observed vehicles. Generally, the critical speed is located in the upper range of the pace speed. Sections 22357 and 22358 of the California Vehicle Code authorize local authorities to establish a prima facie speed limit on the basis of the results of an Engineering and Traffic Survey. The Engineering and Traffic Survey considers such factors as the number of collisions that have occurred on the road segment, roadway features, adjacent land uses, driveway locations, traffic volumes, pedestrian volumes, critical speed, horizontal and vertical alignment, stopping sight distance, and conditions that may not be readily apparent to the driver. RECOMMENDATION: Based upon the results of the Engineering and Traffic Survey, the Traffic Safety Coordinating Committee recommends establishing a 40 mile per hour prima facie speed limit upon The Crossings Drive from Palomar Airport Road to its northerly terminus. NECESSARY CITY COUNCIL ACTION: An ordinance will be required to be adopted by the City Council to establish the 40 mile per hour prima facie speed limit upon The Crossings Drive, as recommended. LOCATION MAP DRIVEWAY TO CITYr TRAIL ACCESS AND WATER TANK I I GRAND PACIFIC DR. C:=, LEGOLAND SERVICE ENTRANCE AND BUS PARKING NOT TO SCALE I ~ 1~$~-1'0 ~,11~111 ~c, I THE CROSSINGS SERVICE ENTRANCE ~ I n, I I %\ \\ \ \ \ \ PROJECT NAME PROPOSED SPEED ZONE THE CROSSINGS DRIVE PROPOSED SPEED ZONE DRAlm BY: SCOTT EVANS, CARLSBAD ENGINEERING DEPT. B 01 OB C: TRAmc SPEED ZONES SPEED ZONE-THE CROSSINGS DRl~.DWG EXHIBIT 1 ( CITY OF CARLSBAD I { ENGINEERING AND TRAFFIC SURVEY STREET: The Crossings Drive LIMITS: Northerly Terminus to Palomar Airport Road A. Prevailing Speed Data: Date of Speed Survey Location of Speed Survey 85th Percentile 10 MPH Pace Percent in Pace Posted S eed Limit B. Midblock Accident History: (8/01/06 through 7/31/08) Speed-Related Accidents Total Accidents Accidents/Million Vehicle Miles (MVM) California Statewide Accidents/MVM C. Traffic Factors: Average Daily Traffic Traffic Controls Pedestrian/Bicycle Traffic Bicycle Lanes On-Street Parking Other D. Roadway Factors: Circulation Element Street Classification Length of Segment Roadway Width Number of Lanes Vertical Alignment Horizontal Alignment Sidewalks Driveways Street Lighting Direction: Northbound/Southbound 8/26/08 680 feet north of Palomar Airport Road 42MPH 33 to 43 MPH 79% No Posted Speed Limit 0 1 0.73 1.81 (2006 State Rate for Same Type of Roadway) 4,709 -North of Palomar Airport Road (7/23/08) Traffic Signal at Palomar Airport Road Light No Designated Bicycle Lanes Parking Prohibited in Some Locations on Each Side Bus Route Unclassified 0.43 Mi. Varies from 40 Feet to 64 Feet (Curb-to-Curb) One Lane Each Direction Roadway Grades Vary from 4.54% to 10% Relatively Straight . Sidewalk on Entire West Side and Northerly 425 Feet of East Side Six Driveways Street Li hts on Both Sides • E. Special Conditions: Travel lanes are separated by either a double-yellow centerline or painted median. F. Adjacent Land Uses: Municipal Golf Course and Restaurant, Water Reservoir, 128-Acre Theme Park, Citywide Trail System, Bike Path/Walkin Path, Resort/Conference Center, Storm Water Detention Basin. G. Remarks/Conditions Not Readily Apparent: Six driveways and one private street intersect with The Crossings Drive. 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 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 ..AQ_MPH is found to be appropriate and ·ustified. NOTE: Appropriate speed survey(s) is /are attached hereto and made a part hereof. DATE: 08/26/08 TIME: 9:1 0 AM TO WEATHER: Clear & Cool ( CITY OF CARLSBAD SPEED SURVEY 10:00 AM TOTAL VEHICLES: CRITICAL SPEED: LOCATION: The Crossings Drive ~680' n/o Palomar Airport Road VEHICLES IN PACE: OBSERVER/RECORDER: M. Rehfeldt SOUTHBOUND DIRECTION OF TRAVEL MPH 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 X 45 X X 44 X X 43 X X X 42 X X X 41 X X X 40 X X X X X 39 X X X X 38 X X X X X 37 X X X X X X 36 X X X X 35 X X X 34 X X X 33 X X 32 X X 31 X X 30 29 28 27 26 25 24 23 22 21 PACE SPEED(S): NONE POSTED SPEED LIMIT # % .l;# % ¾tile % # 1 2 1 1 100 2 4 2 2 99 2 4 2 2 97 3 6 5 5 95 4 2 3 6 8 8 90 10 5 3 6 7 7 82 8 4 5 10 9 9 75 8 4 4 8 9 9 66 10 5 5 10 10 10 57 10 5 6 12 11 11 47 10 5 4 8 7 7 36 6 3 3 6 7 7 29 8 4 3 6 5 5 22 4 2 2 4 6 6 17 8 4 2 4 4 4 11 4 2 2 4 4 4 7 4 2 2 2 3 4 2 1 1 1 2 1 Engineering Department Transportation Division 100 42 MPH ----------- 79 % ----------- 33 TO 43 MPH ---------- NORTHBOUND DIRECTION OF TRAVEL MPH 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 X X 43 X X X X X 42 X X X X 41 X X X X 40 X X X X X 39 X X X X X 38 X X X X X 37 X X X 36 X X X X 35 X X 34 X X X X 33 X X 32 X X 31 X X 30 X 29 28 27 26 25 24 23 22 21