2 Main Uses of Traffic Cameras Are Not To Catch Speeders

traffic cameras are different than red light cameras

Traffic cameras have a wide range of public safety uses including: 

1) Traffic flow. Many cities install traffic flow monitoring devices on roadways and busy intersections in order to measure traffic volume and speed at different times of the day, week, month, or year. The videotapes from these cameras can help engineers understand how people are using streets and highways so that more effective design decisions can be made about future development projects in the area. 

If there's congestion in an intersection, cities can adjust the timing of traffic signals for that particular intersection to help with traffic flow. If there's congestion in an intersection, police can adjust the timing of traffic signals for that particular intersection to help with traffic flow. This is called adaptive signal control. Cameras are used to monitor traffic flow so that when it's needed, an agent can go into a system and adjust the timing at the appropriate intersections during high-volume periods. This helps keep traffic flowing smoothly and prevents backups from happening at key intersections. 

The National Highway Traffic Safety Administration uses these cameras to track traffic patterns and lessen gridlock. Some cities use video feeds from their highway surveillance systems as part of an overall system designed to help motorists navigate through town by making informed decisions about which routes they choose when traveling during different times of day or night.* 

2)  Crimes and accidents. Another use for cameras is safety. Cameras can monitor roads for crimes, such as someone stealing from another car, road rage incidents, accidents (or fender benders), and other things that may need attention from law enforcement. Police officers can use these cameras to track down criminals, stolen vehicles, and missing people. Crime prevention is another benefit that traffic cameras offer; they deter potential criminals from committing a crime because they know their photo will be captured on the camera.

Because incidents like robberies or hit-and-run accidents often occur near busy roads and highways, police departments sometimes use camera systems as tools for investigating these crimes when they take place near traffic cameras (only if there is no obvious violation). Traffic camera video and photos can be used to document accidents or crimes.  Each city archives video for a certain period of time so if you get in an accident you can subpoena the footage as evidence. 

Emergency response. Cities also use their video feeds to track the activity on city streets as part of their emergency response system; if an accident occurs on a major highway, officials can review previous videos taped by nearby cameras in order to better understand what happened when emergency responders arrive on the scene.