One such method of optimizing the existing highway system is through implementation of the Automated Traffic Surveillance and Control (ATSAC) System. Based on the successful performance of the Coliseum Area ATSAC System during the 1984 Olympic Games, the ATSAC System is being implemented Citywide. To date, ATSAC has been implemented at 2,895 of 4,244 City of Los Angeles signalized intersections, with another 151 being designed and 248 under construction this year. We have received funding commitments for an additional 707 intersections, which will leave 243 locations or six percent of the system yet to be funded and constructed. Non-City grant funding has provided approximately two thirds of all implementation costs.

ATSAC is a computer-based traffic signal control system that monitors traffic conditions and system performance, selects appropriate signal timing (control) strategies, and performs equipment diagnostics and alert functions. Sensors in the street detect the passage of vehicles, vehicle speed, and the level of congestion. This information is received on a second-by-second (real-time) basis and is analyzed on a minute-by-minute basis at the ATSAC Operations Center, located four floors below street-level in City Hall, to determine if better traffic flow can be achieved by changing the signal timing. If required, the signal timing is either automatically changed by the ATSAC computers or manually changed by the operator using communication lines that connect the ATSAC Center with each traffic signal. To supplement the information from electronic detectors, closed-circuit television (CCTV) surveillance equipment has been and continues to be installed at critical locations throughout the City. The Department has installed CCTV cameras at 244 locations and new sites are being added.