Knowledge Resources

Intersection-related crashes decreased 11 percent overall at signal controlled intersections in Texas after the installation of automated traffic enforcement systems.(June 2011)

Synchronizing traffic lights on Alicia Parkway, a major corridor in California, reduced the number of stops by 75 percent and lowered greenhouse gas emissions by 7 percent.(May 25, 2011)

In Espanola, New Mexico the implementation of a traffic management system on NM 68 provided a decrease in total crashes of 27.5 percent and a reduction in vehicle delay of 87.5 percent.(September 2, 2008)

In the City of Fort Collins, Colorado, the installation of an Advanced Traffic Management System reduced travel times up to 36 percent.(24 June 2008)

In St. Paul, Minnesota, an advanced parking management system reduced travel times by nine percent.(January 2007)

In Monroe County, New York, the closed-circuit television (CCTV) camera provided traffic operators the availability of visual information so they can examine real time incident conditions and provide a higher and more responsive quality of service to the traveling public.(August 2006)

The Texas Traffic Light Synchronization program reduced delays by 24.6 percent by updating traffic signal control equipment and optimizing signal timing.(7-10 August 2005)

The Traffic Light Synchronization program in Texas demonstrated a benefit-to-cost ratio of 62:1(7-10 August 2005)

Evaluation data show that adaptive signal control strategies can improve travel times in comparison to optimized signal timing plans.(2 February 2005)

Signal retiming projects in several U.S. and Canadian cities decreased delay by 13 to 94 percent, and improved travel times by 7 to 25 percent.(April 2004)

In Los Angeles, transit signal priority reduced total transit travel time by approximately 25 percent.(July 2001)

In Tucson, Arizona and Seattle Washington models indicated adaptive signal control in conjunction with transit signal priority can decrease delay for travelers on main streets by 18.5 percent while decreasing delay for travelers on cross-streets by 28.4 percent.(7-13 January 2001)

Adaptive signal control systems deployed in five metropolitan areas have reduced delay 19 to 44 percent.(December 2000)

Adaptive signal control systems reduced vehicle stops by 28 to 41 percent; improve safety.(December 2000)

Adaptive signal control can lower operations and maintenance costs.(December 2000)

Arterial information allows travelers to make more informed decisions.(December 2000)

Modeling indicated that coordinating fixed signal timing plans along congested arterial corridors leading into Seattle, Washington, and incorporating arterial traffic flow data into the traveler information system would reduce vehicle delay by 7 percent and 1.8 percent, respectively.(30 May 2000)

A model found that coordinating fixed signal timing plans along congested arterial corridors leading into Seattle, Washington would help reduce the number of expected crashes by 2.5 percent and the frequency of fatal crashes by 1.1 percent.(30 May 2000)

Users of the Advanced Traveler Information System in Seattle, Washington were satisfied with the information on freeway and transit conditions provided via Web sites and a Traffic TV service.(30 May 2000)

Traffic signal coordination among two jurisdictions in Arizona resulted in a 6.2 percent increase in vehicle speeds; optimization of the coordinated timing plans was predicted to reduced AM peak period delay by 21 percent.(April 2000)

In Arizona, traffic signal coordination among two jurisdictions contributed to a 1.6 percent reduction in fuel consumption and a 1.2 increase in carbon monoxide emissions. (April 2000)

Crash risk along a corridor in Arizona was reduced by 6.7 percent due to traffic signal coordination among two jurisdictions.(April 2000)

Deploying advanced technologies and an integrated corridor management approach decreased congestion and improved traffic flow within an 8-mile corridor south of Twin Cities, Minneapolis encouraging 58% of motorists surveyed to use arterial streets for short trips rather than Interstate-494.(April 2000)

The payback period for expansion of an adaptive signal control system in Toronto, Canada was estimated at less than two years.(8-12 November 1999)

An adaptive signal control system in Toronto, Canada increased traffic flow speeds by 3 to 16 percent. (8-12 November 1999)

An adaptive signal control system in Toronto, Canada reduced vehicle emissions by 3 to 6 percent and lowered fuel consumption by 4 to 7 percent.(8-12 November 1999)

In Toronto, Canada adaptive signal control reduced ramp queues by 14 percent, decreased delay up to 42 percent, and reduced travel time by 6 to 11 percent; and transit signal priority reduced transit delay by 30 to 40 percent and travel time by 2 to 6 percent. (8-12 November 1999)