Video Detection Cameras
Smile! You’re on Intersection Cameras.
El Paso County is working to install video cameras at each of our signalized intersections during 2004. The cameras are part of “video detection,” used to improve traffic operations on area streets. So what will these cameras do?
EPC is using them to replace in-pavement magnetic loops for signal control. Today magnetic loops help detect where and how many cars sit at a signal, so the signal can adjust its timing to best serve the most vehicles. Magnetic in-pavement loops have reliability problems from failure due to weather, pavement maintenance, or utility cuts, giving around five years average service life. They also have trouble detecting vehicles that don’t have the “right” magnetic signature, such as tandem trucks or motorcycles.
Nervous about privacy? Some people worry that video detection cameras can identify individuals or objects inside vehicles. However, these cameras are selected for durability and economy, not for high resolution. Also, unlike close-range security cameras, traffic cameras are set high to view the entire intersection and avoid looking into headlights, or sunlight or streetlight reflections off vehicle glass. In short, they are good enough to see where a vehicle is located, but not good enough to see inside a vehicle.
Video detection provides more accurate traffic control at less overall cost. Each camera is set up to view individual lanes and “see” when backups occur in each lane of each intersection approach (called zones). Each camera can monitor as many as 24 zones, so only a few are needed even at very large intersections. Cameras are typically reliable for 20-25 years — at least four times as long as magnetic loop detectors.
Cameras can be used for things other than signal control. In some communities, video is used for detecting stoplight “runners,” or to catch toll road users that don’t pay at the gate. In other places, there are emergency management agencies that monitor cameras to detect accidents or broken-down vehicles that cause traffic backups. Where weather is a serious concern, the cameras provide maintenance crews a real-time, local spot-check on weather conditions throughout the area. Lastly, they can provide traffic counts and levels of service data that help to plan for future traffic needs.
Where other places have already installed cameras (including the City of Colorado Springs), the fears of privacy invasion generally fade and the traffic benefits are well-documented. We can soon look forward to providing better service at less cost throughout El Paso County.
