California Department of Transportation
 

 

Q How many CCTV cameras are in use in California?
   
A.

There are 452 CCTV cameras in operation statewide. Caltrans has installed about 430 closed-circuit television cameras (CCTV's) on State Highways (primarily freeways) around the state. City Traffic Departments and County Departments' of Public Works have also installed CCTV's on some of their arterial roads. Some of these CCTV's monitor intersections while others monitor highways. The CCTV's at intersections are actually used to control the traffic signal timing. The image from the CCTV is transmitted to a computer which processes the image to determine the presence (or lack of presence) of vehicles. This Video Image Processing System (VIPS) technology for highway operations and control is still in its infancy, but is gaining credibility by practitioners realizing its tremendous potential to improve traffic signal control operations. The cameras alongside freeways have pan, tilt and zoom capabilities. These cameras are used to monitor freeway conditions and are especially useful when traffic incidents occur. The cameras provide the Transportation Management Center (TMC) operators with a view of the incident scene which allows a quick assessment of the situation, an accurate dispatch of equipment and personnel to the scene, and an idea of the impacts the incident is having on traffic flows. The TMC then develops and releases appropriate motorist information notices through a variety of mediums. Caltrans engineers determine where the cameras should be located. They attempt to install the cameras such that all segments of the freeway system are within view. Most cameras provide full-motion video (30 frames per second), but some cameras only provide a frame rate of 5 to 10 frames per second. The only cameras used for law enforcement are those cameras that are installed at toll bridges or toll roads. These cameras capture the license plate number of a vehicle that does not pay the toll bridge or toll road fee. At this time, there are no camera images provided via the internet. However, Caltrans is working on this and should have some CCTV images available for view on the internet by the first of the year.