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HomeMy WebLinkAbout2015-09-14; Traffic Safety Commission; ; Evaluate safety on Rancho Santa Fe RoadCOMMISSION MEETING OF: CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT September 14, 2015 ITEM NO. GA LOCATION: Rancho Santa Fe Road, from north city limits to Olivenhain Road INITIATED BY: City Traffic Engineer REQUESTED ACTION: Evaluate safety on Rancho Santa Fe Road BACKGROUND: Rancho Santa Fe Road is a six-lane, divided roadway that serves as a north/south corridor between the neighboring cities of San Marcos and Encinitas (see Exhibit 1). Rancho Santa Fe Road is classified as a Prime Arterial and has been appropriately designed to accommodate 40,000 or more vehicles per day at speeds of 60 MPH according to the City of Carlsbad Street Design Criteria (Exhibit 2). Rancho Santa Fe Road is fully improved with curb, gutter, sidewalks, bicycle lanes and street lights on both sides of the street. There are two speed zones established on Rancho Santa Fe Road which are justified by valid Engineering and Traffic Surveys as required by the State of California. The segment between the north city limits and La Costa Avenue is posted at 55 MPH (Exhibit 3) and the segment between La Costa Avenue and Olivenhain Road is posted at 50 MPH (Exhibit 4). EXPLAINING SPEED LIMITS: Roads in Carlsbad are designed in accordance with engineering standards to satisfy the goals of having a safe roadway, providing mobility, offering mode choices, and enhancing efficient traffic flow. One way that these goals are achieved is by establishing proper and reasonable speed limits that can be enforced. California state law establishes speed limits that are reasonable so that voluntary compliance is achieved by the majority of drivers without need for the presence of a police officer. 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 effective, drivers must believe that the posted speed limit is safe, properly established, and legally enforceable. If speed limits are established arbitrarily low, the majority of drivers would be violators of the speed limit, public confidence would be sacrificed and respect for official traffic control devices such as speed limit signs would be diminished. The predominant practice for managing speed is by establishing a prima facie speed limit according to California state law. 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 Page 1 COMMISSION MEETING OF: (continued) CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT September 14, 2015 ITEM NO. 6A limits have been set on a reasonable basis, the enforcement efforts of the Carlsbad Police Department are more effective. The nationally vetted practices and guidance found in the California Manual on Uniform Traffic Control Devices (CA MUTCD) and the legal statutes found in the California Vehicle Code (CVC) provide the basis for setting speed limits in California. 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. Speed limits should not be lowered for conditions that are readily apparent to the driver. For conditions not readily apparent to motor vehicle operators, appropriate warning signs are installed in advance of changing roadway conditions such as intersections or curved roadway sections. RELATIONSHIP BETWEEN CRITICAL SPEED AND POSTED SPEED LIMIT: The critical speed or 85th percentile speed is the speed at which 85% of the drivers surveyed are driving at or below. The premise implied in speed zoning is that the majority of drivers are operating their vehicles at or near the 85th percentile speed. Drivers that operate their vehicle at speeds higher than the 85th percentile speed should be the focus of the police enforcement as excessive speed can be a factor in a vehicle collision. The current (2012) edition of the CA MUTCD states: "When a speed limit is to be posted, it shall be established at the nearest 5 mph increment of the 85th-percentile speed of free-flowing traffic, except as shown in the two Options below. 1. The posted speed may be reduced by 5 mph from the nearest 5 mph increment of the 85th-percentile speed, in compliance with eve Sections 627 and 22358.5. See Standard below for documentation requirements. 2. For cases in which the nearest 5 mph increment of the 85th-percentile would require a rounding up, then the speed limit may be rounded down to the nearest 5 mph increment below the 85th percentile speed, if no further reduction is used. Refer to eve Section 21400(b). Standard: If the speed limit to be posted has had the 5 mph reduction applied, then an E& TS shall document in writing the conditions and justifications for the lower speed limit and be approved by a registered Civil or Traffic Engineer. The reasons for the lower speed limit shall be in compliance with eve Sections 627 and 22358.5." Page 2 COMMISSION MEETING OF: (continued) CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT September 14, 2015 ITEM NO. 6A For example, if the 85th-percentile speed was found to be 37 mph, the speed limit would be posted at 35 mph since it is the closest 5-mph increment to the 85th-percentile speed. If the 85th-percentile speed was found to be 38 mph, the speed limit could be posted at 40 mph since it is the closest 5-mph increment OR, exercising Option 2, the speed limit could be posted at 35 mph, with no further reduction possible. In Carlsbad, Option 2 is always utilized in situations that allow its use. Looking specifically at the speed zone established on Rancho Santa Fe Road between the North city limits and La Costa Avenue, the critical speed was measured at three locations and found to be 56 mph, 59 mph and 59 mph. The closest 5-mph increment to 56 mph is 55 mph. The closest 5-mph increment to 59 mph is 60 mph but can be rounded down to 55 mph based on Option 2. Therefore, 55 mph is the appropriately justified speed limit on this portion of Rancho Santa Fe Road. Similarly, the 50 mph speed zone established on Rancho Santa Fe Road between La Costa Avenue and Olivenhain Road was justified by a single critical speed measurement of 50 mph. The Option 1 reduction is restricted in its use as noted above. The "California Manual for Setting Speed Limits" published on May 9, 2014, by the California Department of Transportation states, "When roadside development results in traffic conflicts and conditions which are not readily apparent to drivers, speed limits somewhat below the 85th percentile may be justified; however, speed limits shall not be lowered more than 5 mph less than the nearest increment of the 85th percentile speed. The factors justifying a reduction below the nearest increment to the 85th percentile speed are the same factors mentioned above. Whenever such factors are considered to establish the speed limit, they should be documented on the speed zone survey or the accompanying engineering report. Generally, collision history is the most decisive evidence of conditions not readily apparent to the driver. 11 SIGNIFICANCE OF COLLISION DATA: Therefore, 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, and 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 State of California collision rates may be an indicator of a potential for reducing Page 3 COMMISSION MEETING OF: (continued) CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT September 14, 2015 ITEM NO. GA 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. COLLISION DATA FOR RANCHO SANTA FE ROAD: For this staff report, collision data for Rancho Santa Fe Road was compiled for the time period starting from January 1, 2013 and ending on June 30, 2015. Rancho Santa Fe Road between Melrose Drive and La Costa Avenue experienced a total of 41 collisions during this time period, including 24 collisions involving injury and one collision involving a fatality. The fatality occurred at the intersection of Rancho Santa Fe Road and Camino Junipero on May 10, 2015 and the primary collision factor was determined to be driving under the influence of a drug(s). Based on the length of the roadway segment, the average daily traffic and the time period analyzed, the collision rate is 0.69 collisions per million vehicle miles. The corresponding State of California collision rate for a multilane divided arterial is 1.45 collisions per million vehicle miles. Since the collision rate for Rancho Santa Fe Road is significantly lower than the State collision rate, there is no justification to reduce the posted 55 mph speed limit on this portion of Rancho Santa Fe Road per Option 2 of the CA MUTCD described previously. Collision data was also compiled during the same time period for Rancho Santa Fe Road between La Costa Avenue and Olivenhain Road. On this portion of Rancho Santa Fe Road there was a total of 29 collisions, of which there were 15 collisions involving injury and one collision involving a fatality. The fatality occurred at the intersection of Rancho Santa Fe Road and Calle Barcelona on February 24, 2014. The primary collision factor was failing to stop for a red traffic signal. The collision rate for this portion of Rancho Santa Fe Road was found to be 0.50 collisions per million vehicle miles. This collision rate is significantly lower than the State collision rate of 1.45 collisions per million vehicle miles and staff finds no justification to reduce the posted speed limit of 50 mph. 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 Page 4 COMMISSION MEETING OF: (continued) CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT September 14, 2015 ITEM NO. GA 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 . RECOMMENDATION: Based on the results of the studies conducted by staff, changes to the posted speed limit of 55 mph on Rancho Santa Fe Road between the north city limits and La Costa Avenue and 50 mph on Rancho Santa Fe Road between La Costa Avenue and Olivenhain Road are not recommended. Staff recommends that the following measures be considered for implementation on Rancho Santa Fe Road to enhance safety: 1. Reducing the vehicle lane widths and striping a bicycle buffer between the bicycle lane and the #3 vehicle lane. This work will be incorporated into the city's pavement management program and implemented when Rancho Santa Fe Road is re -surfaced. 2. Installation· of radar speed feedback signs on Rancho Santa Fe Road to highlight the transition between the 50 mph and 55 mph speed zones. 3. Enhancing the existing marked crosswalks at the intersection of Rancho Santa Fe Road and Calle Barcelona with ladder markings. NECESSARY CITY COUNCIL ACTION: None. Page 5 NOT TO SCALE LOCATION MAP LEGEND: -55 MPH Speed Zone I II 111 50 MPH Speed Zone e Traffic Signal Rancho Santa Fe Road Speed Zones (I] La Costa Town Square [!] La Costa Canyon High School IT] Mission Estancia Elementary School EXHIBIT 1 m X :, er ;;: N TABLE A CITY OF CARLSBAD STREET DESIGN CRITERIA DESIGN CLASSIACATION ANTICIPATED ADT RANGES Deskin Speed Minimum Spacing of Intersections (including right-turn in/out) (in feet) Right-of-Way Width (in feel) Private Access to Adjoining Property Curb-to-Curb Distance (in feet) Minimum Traffic Index Minimum Structural Section (in inches) <5> Stopping Sight Distance <Sl (in feet) Corner Siciht Distance <9> (in feet) Minimum Centerline Radius (in feet) Maximum Centerline Grade thru intersec. )C◄> Minimum Flowline Grade NOTES: (1)N.A. (not PRIME ARTERIAL 40,000 OR MORE 6OMPH 2,600 126 None 106 (18' median) g 6AC 6AB 580 660 2,400 (5) 7% 1.0% (2)Reduction lo 100' with approval of City Engineer. MAJOR .ARTERIAL 20,000 TO 40,000 50 MPH 1,200 102 None 82 (18' median) 8.5 5AC 6AB 430 550 1,400 <5> 7% 1.0% (3)Grades greater than 10% will require specific approval, chip seal, etc. (4)Not to exceed 6% thru intersections. Local, cul-de-sac and hillside may increase grade through intersections up to 8%, provided that CAL TRANS guidelines for sight distance and vertical curves are complied with. SECONDARY ARTERIAL 10,000TO 20,000 40MPH 600 84 Where no other access is possible 64 8.0 4AC 6AB 300 440 670 10% 1.0%· (5)stopping Sight Distance per CALTRANS Highway Design Manual Topic 201 and Volume 3 Section 8 in Chapter 3 of City Standards. (6)Assumes no superelevations; includes standard crossfall. (?)Minimum grade of 2.0% is encouraged. If 1.0% minimum is not possible, special construction may be used with City Engineer approval. Gutter line of cul-de-sac bulbs and knuckles shall have minimum grade of 1.0%. COLLECTOR INDUSTRIAL LOCAL CUL-OE-SAC HILLSIDE STREET STREET STREET STREET ALLEY STREET 2,000 TO -20TO 20TO 10,000 2;000 1000 --"-- 3OMPH 30 MPH 25MPH 25MPH --20MPH 300 300 15OT's 150 T's --150 others others 200 200 60 or 68 72 60/68<11> 55<12l/6O/68<11> 24 64 Limited subject Limited subject O.K. O.K. O.K. Limited subject to approval 40 or 48 6.0 4AC 6AB 200 330 300 12%<3) 1.0% to approval 52 34/42<11> 35<12>140142<11> 7.0 5.0 4.5 4AC 4AC 4AC 6AB 4AB<10> 4AB<10> 200 150 150 330 275 275 300 200 200 8% 12%(10) 12%(10) 1.0% 1.0% 1.0% Typical centerline grades al the upper reach of cul-de-sacs shall be 2% minimum. 24 4.0 5-1/2" PCC <a> - - --- ---- 1.0% (8) Alley sections shall conform to SDRSD G-21 . (9)Corner Sight Distance per Caltrans Highway Design manual Topic 405 and Volume 3 Section 8 in Chapter 3 of City Standards. (10) PCC pavement required for grades over 10% to approval 42 5.0 4AC 4AB<10> 125<2> 220 200 15%(10) 1.0% (11 l 28-foot clear travel way required where adjacent lots contain any portion of a Fire Hazard Zone/Fire Suppression Zone within the property line. (12) 36-foot curb-to-curb distance permissible when serving 24 or fewer lots and where adjacent lots do not contain any portion of a Fire Hazard Zone/Fire Suppression Zone within the property line. Page 4 of 4 CITY OF CARLSBAD ENGINEERING AND TRAFFIC SURVEY STREET: Rancho Santa Fe Road LIMITS: North City Limit to La Costa Avenue FACTORS Direction: Direction: Direction: A. Pr:evalling S[!eed Data: Northbound/Southbound Northbound/Southbound Northbound/Southbound Date of Speed Survey 7/29/08 7/29/08 7/29/08 Location of Speed Survey 550 feet n/o San Elijo Road 0.3 mi. n/o Cam ino Junipero At Paseo Lupino 85th Percentile 56MPH 59MPH 59MPH 10 MPH Pace 48 to 58, 49 to 59 MPH 49 to 59, 50 to 60 MPH 50to 60 MPH Percent in Pace 75% 79% 83% Posted Soeed Limit 55MPH 55MPH 55MPH B. Mldblock Accident Hlsto[Y: (9/01 /06 through 8/31108) Speed-Related Accidents 14 Total Accidents 26 Accidents/Million Vehicle Miles (MVM) 0.41:! California Statewide Accidents/MVM 1.84 (2006 State Rate for Same Type of Roadway) C. Traffic Factors: Average Daily Traffic 31,368 -North of San Elijo Road (8/20/08); 36,074 -North of Camino Junipero (8/06/08) Traffic Controls Six Signalized Intersections Pedestrian/Bicycle Traffic Low Bicycle Lanes Bicycle Lane on Each Side On-Street Parking Parking Prohibited on Each Side Other Bus Route; Truck Route: Bike Route per Circulation Element of the General Plan D. Roadwall Factors: Circulation Element Street Classification Prime Arterial Length of Se8ment 2.18 miles Roadway Wi th Roadway Width Varies between 102 Feet and 112 Feet (Curb-to-Curb) Number of Lanes Three Lanes Each Direction Vertical Ali~nment Roadway Grades Vary from l . 7 4% to 5 .. 62% Horizontal lignment Curvilinear Sidewalks Sidewalk on Each Side Except 800 Feet on West Side and 3,300 Feet on East Side Driveways Five Driveways Street UQhtinQ Street Lights on Both Sides Except from Paseo Lupino to 1,850 Feet North on East Side E. Special Conditrons: Rancho Santa Fe Road serves regional traffic. Travel lanes are separated by a raised median that is mostly landscaped. Police motorcycle officers utilize depressions at midblock locations in the raised median for U-·lums. Several bus turnouts provided in this segment. Right-turn-only lanes exist at the intersections of Paseo Lupino, Camino Junipero, Avenida Soledad, San Elijo Road, and La Costa Meadows Drive. Emergency response vehicles enter the road intermittently from a siQnalized drivewav servino onlv a Carlsbad fire. station. ' F. Adlacent Land Us&s: Water Reclamation Facility, Industrial/Business Park including Light Commerc1<1I, Single-Fami~ and Mult1-ramily Residential, Open Space, Creek, Bus Stops, RV Storage, Fire Station. Affordable Housing Development, and uture Maior Shoooinq Center. G. Remarks/Conditions Not Readily Apoarent: Construction vehicles enter/exit the roadway at various locations due to ongoing construclion acl1v1iv. Tfie west leas of the intersections at San Eliio Road and Avenida Soledad are under construction. H. Traffic En~lneer's Recommendation (Explanation): This speed zone satisfies the conditions of Section 627 of the California Vehicle Co e and has been prepared and evaluated in accordance with the California Manual on Uniform Traffic Control Devices with respe_ct to design and pr~vaillng speeds, accident records, p~destrlan and bicyclist ~afety, Intersection and driveway spac!ng, and roadside and traffic condIhons not readily apparent to the dnver. A speed lIm1t posting of §.Q MPH Is found to be appropna1e and iustified. I. e,poroya!s: ~ecertification of e.xisting speed zone per Sections 22357. 22358 and 40802 of the California Vehicle Code. D Establishment of new speed zone. Approved \Gtl(¼tj--::t:J..l...!±'I,. r' L / j,. I. f!; City 1:ng,neer ~ 7 Dale ~ ------NU It:. Appropriate speed survey(s) ,s /are attached hereto and made a part hereof, Exhibit 3 CITY OF CARLSBAD ENGINEERING AND TRAFFIC SURVEY STREET: Rancho Santa Fe Road LIMITS: La Costa Avenue to Olivenhain Road/Camino Alvaro FACTORS Direction: A. P!rs'.lillng §D!1!!"1 l21m: Northbound/Southbound Date of Speed Survey 7/22/13 Location of Speed Survey 0.25 Ml. South of La Costa Avenue 86th Percentile 60MPH 10MPH Pace 42 to 52 MPH Percent In Pace 83% B. Aicicldent ljlstocx: (8/01/11 through 7/31/13) Speed-Related Accidents 11 Pedestrian and/or Bicycle Accidents 0 Total Accidents 18 C. Traffic Factors: Average Dally Traffic Traffic Controls 33,200 -South of La Costa Avenue (3/19/09); 36,200 -South of Calle Barcelona (1/05/11) Traffic Signals at Calle Barcelona, Camino de los Coches, La Costa Avenue, and Olivenhaln Road/Camino Alvaro Pedestrian/Bicycle Traffic Low Bicycle Lanes Bicycle Lane on Each Side On-Street Parking Parking Prohibited on Each Side Other Bus Route & Truck Route; Bike Route oer Circulation Element of the General Plan D. Boadwa)l Factors: Street Classification Prime Arterial Length of Segment 1.08Mi. Roadway Width 93 Feet (Curb-to-Curb) Number of Lanes 3 Lanes Each Direction; SB Travel Lanes are Reduced to 2 Lanes Approaching Camino Alvaro Vertical Alignment Roadway Grades Vary from 0.59% to 7.75% Horizontal Alignment Curvilinear Sidewalks Sidewalk on Each Side Driveways One Commercial Driveway Street Lighting Street Liahts on Each Side E. Soeclal Conditions: Four of the ten speed-related accidents occurred durina rainv conditions or on wet roadways. F. Adlacent Land Uses: Sinale-Familv Residential, Elementarv School, Church, Two Retail Shoooing Centers G. Remarks/Conditions Not Readllll Apparent: This road segment Is a portion of a regional arterial system that serves adjacent communities to the freeway corridor. An elementary school crossing exists on Rancho Santa Fe Road at Calle Barcelona. There is also a 25.7 acre park and a high school served bYi this arterial located on Camino de Los Coches. Southbound travel lanes are reduced to two throuah lanes and one rii:iht tum-on v lane aooroachlna Olivenhain Road. 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 January 13, 2012, with respect to design and prevailing speeds, accident records, pedestrian and bicyclist safety, intersection and driveway spacin~, and roadside and traffic conditions not readily apparent to the driver. A speed limit 0ostlna of 50 MPH Is found to be annroonate and lustified. ,. ::: I : R cation of existing speed zone per Sections 22357, 22358 and 4~0802(Jof the California Vehicle Code. 0 Establishment of new speed zone. Approved ) -r/J,z/13 Bryan D., ;J<)nes TE, PTP, AICP 'Date Deputy m ,rector/City Traffic Engineer CA TR2229 NOTE: Appropnate speed survey(s) 1s /are attached hereto and made a part hereof. Exh ibit 4