Case Study No. 27
Prepared by Michelle DeRobertis, Wilbur Smith Associates, San Francisco, CA and Raymond D. Chong, Assistant Director of Public Works, City of Fairfield, CA.
Between 1995 and 1997, 32 traffic collisions occurred in the McClellan Road corridor. Given the confluence of commuter, school, and other traffic generated from a nearby junior college and a junior high school, the City and its residents were concerned about pedestrian safety for the students of an elementary school and a high school located on the busy roadway.
A crossing guard helps Lincoln Elementary School students cross McClellan Road.
Lincoln Elementary School and Monta Vista High School, with an enrollment of almost 3000 students, are adjacent to each other on McClellan Road, a collector with single-family residential frontage. McClellan Road is a three-lane major collector with bicycle lanes, two 3.1 m (10 ft) wide travel lanes and a narrow center left-turn lane. The speed limit is 40 km/h (25 mi/h) in the school zone. McClellan Rd carries about 8,500 vehicles per day traveling at speeds (85th percentile) of 58 km/h (36 mi/h), and it has a high traffic accident rate.
The City developed a multi-pronged project to improve pedestrian safety for students in the school zone. The objectives of the project were:
The project was conducted in partnership with the Cupertino Union School District, Fremont Union High School District, Santa Clara County Sheriff Department, and the Santa Clara County Health Department. Engineering, education and enforcement activities were implemented simultaneously with partner agencies leading the activities that fell under their jurisdiction, such as enforcement of traffic laws during peak hours, educating students on pedestrian safety, collecting before and after data, and conducting a public opinion survey.
For engineering changes, the City proposed the installation of In-Roadway Warning Lights (IRWLs) as the best way to increase protection for students crossing the street. IRWL systems include lights that are located in the roadway along the edges of the crosswalk markings. The lights create higher visibility crosswalks to improve crossings and reduce vehicle speeds.
Flashing school zone beacons complement the in-roadway crosswalk warning lights.
Under direction of the City Traffic Engineer, the design chosen for the IRWL system utilized high intensity bi-directional halogen lights. The IRWLs at the crosswalks are in operation 24 hours per day, 7 days per week, and are activated automatically using “Smart Walk” pedestrian detectors, a microwave technology to detect the presence of pedestrians waiting to cross or in the crosswalk.
In addition to installing IRWL systems at two crosswalks in the school zone, other engineering measures included placing flashing school zone beacons to indicate 40 km/h (25mi/h) signs and enhancing roadway signs and pavement markings.
Total cost for the two IRWL systems was $68,000 and the Traffic Safe Communities Network (TSCN) of Santa Clara County provided funding for the IRWL systems. The TSCN, sponsored by the Santa Clara County Health Department, is a consortium of public agencies, organizations, and businesses working together to improve traffic safety.
The City collected data on motor vehicle speeds before the project, in May 1999, and after, in May 2000. The results showed a reduction of 85th percentile speeds from 58 km/h (36 mi/h) to 53 km/h (33 mi/h). Median speeds were reduced from 50 km/h (31 mi/h) to 43.5 km/h (27 mi/h). Because a reduction in vehicular traffic volume or anincrease in pedestrian traffic was not a specific goal of the project, data was not collected on these factors.
The installation of the two crosswalk IRWL systems on McClellan near Lincoln Elementary School and Monta Vista High School has successfully improved pedestrian safety. Response from the community and users has been positive.
The supplemental use of speed limit warning flashers has enhanced the effectiveness of the IRWLs by drawing driver attention to the pedestrian crossing, thereby reducing speeds. In addition to improving the pedestrian environment by slowing traffic speeds, vehicle crashes decreased from 11 per year before the project to 7 in the year afterward.
City of Cupertino
10300 Torre Avenue
Cupertino, CA 95014
Phone: (408) 777-3245
Associate Civil Engineer
City of Alameda
950 West Mall Square
Alameda, CA 94501
Phone: (510) 749-5918
Assistant Director of Public Works
City of Fairfield
2000 Cadanesso Drive
Fairfield, CA 94533
Phone: (707) 428-7632
California Traffic Control Devices Committee.
Manual of Uniform Traffic Control Devices, 2000 Edition, and In Roadway Flashing Lights at Crosswalks, an Informational Report published by the Institute of Transportation Engineers.