Signal Timing Initiative Delivers Big Boost for Bay Area Mobility

News provided by

Metropolitan Transportation Commission

Feb 14, 2012, 03:37 ET

OAKLAND, Calif., Feb. 14, 2012 /PRNewswire/ -- A new program to promote the synchronizing of traffic signals owned by Caltrans with those owned by Bay Area cities and counties is delivering benefits — including shorter travel times, reduced tailpipe emissions and improved safety for bicyclists and pedestrians — that outpace costs by a ratio of 80 to 1.

The Metropolitan Transportation Commission (MTC), in partnership with Caltrans and local governments, has completed the first 13 signal timing projects through its Program for Arterial System Synchronization (PASS), which provides technical and financial assistance to Bay Area agencies to improve the safety and efficiency of traffic signal systems in select corridors. Analysis of the $1.25 million first round of PASS projects — which involved 339 traffic signals in seven counties during the 2010-11 fiscal year — pegs the total value of the mobility and emissions improvements at more than $101 million over the next five years. Cumulative results anticipated from the initial cycle include:

Travel time savings for autos: 18 percent, or more than 3.8 million hours
Auto speed increase: 26 percent
Travel time savings for transit: 7 percent or almost 48,000 hours
Transit speed increase: 9 percent
Auto fuel consumption savings: 14 percent or more than 9.87 million gallons
Reduction in reactive organic gases (ROG) emissions: 88.81 tons
Reduction in oxides of nitrogen (NOx) emissions: 94.19 tons
Reduction in particulate matter (PM10) emissions: 9.97 tons
Total emissions reductions from autos: 712.39 tons.

"PASS is a key part of MTC's larger Freeway Performance Initiative," explained MTC Chair and San Mateo County Supervisor Adrienne Tissier, noting the program largely encompasses major arterials parallel to the Bay Area freeway system. "Like the rest of the freeway initiative, it delivers a very big return on a comparatively modest investment."

Tissier pointed specifically to a pair of PASS projects in San Mateo County in which Caltrans teamed with the cities of Redwood City and South San Francisco. "These projects included 10 signals along El Camino Real, Westborough Boulevard and Chestnut Avenue in South San Francisco, where we've seen a 24 percent drop in travel times, plus 8 signals along Middlefield Road in Redwood City, where travel times are down by 21 percent. Add in the fuel savings and reduced emissions from idling vehicles and the benefit/cost ratios are 51:1 in Redwood City and 100:1 in South San Francisco."

MTC Vice Chair and Orinda City Councilmember Amy Rein Worth noted similar results from a project involving Caltrans and Walnut Creek to synchronize 87 signals throughout the city. "The Walnut Creek project was by far the largest in the first round of PASS initiatives and yielded benefits that exceed costs by a ratio of 93 to 1. I expect the next cycle of PASS projects to deliver the same bang for the buck."

Traffic signals owned by Caltrans typically are located along major arterials such as El Camino Real in San Mateo and Santa Clara counties, Mission Boulevard in the East Bay or Van Ness Avenue in San Francisco that are part of the state highway system, or control intersections at the entrance to or exit from freeways. PASS projects' safety benefits for bicyclists come from increasing the minimum "green times" in each direction. Pedestrian safety is enhanced by re-timing walk signals to accommodate pedestrians traveling at a walking speed of 3.5 feet per second rather than the previous standard of 4 feet per second. To improve safety for children and seniors, the PASS program allows for implementation of even greater pedestrian clearance times at intersections near schools or senior centers.

The next round of PASS investments will cost about $1.25 million and include 21 separate projects with a total of 360 traffic signals in Alameda; Berkeley; Brentwood; Danville; East Palo Alto; Fairfield and Suisun City; Fremont; Larkspur; Menlo Park; Mountain View; Napa; Oakland; Petaluma; San Leandro; San Rafael; San Ramon; Santa Clara; South San Francisco; and Windsor; as well as in unincorporated areas of San Mateo and Santa Clara counties. All these projects are slated for completion by mid-2012. The five-year time frame for analysis of PASS projects' impact is based on the expectation that signals will be retimed after five years.