Live highway traffic cameras are used to monitor traffic flow and road conditions and to enable first responders to get to traffic accidents more quickly. Law enforcement agencies may use them to track suspects, and their footage may also provide evidence. Caltrans, in California, allows people to download and view the traffic information on a PC or on other mobile devices. Additional software, such as Windows Media Player, Adobe Flash or QuickTime may be needed.
California has one of the most extensive networks of roadway cameras. More than 1,000 cameras keep track of the roadways, some of them providing live streaming video. The Caltrans website lists the live traffic cameras. The W 80 SFOBB at Incline camera, for instance, shows viewers the traffic at the toll booths on the Oakland end of the Bay Bridge. If traffic is backed up quite a bit, a traveler may decide to wait a bit before heading out.
Closed-circuit TV footage of major roadways is also available. For example, the cameras for Interstate 5, which travels the length of California, are listed on a map with real-time pictures available. The Grapevine, a stretch of I-5 in southern California, is known for its unpredictable weather during the winter. The highway cameras show actual weather conditions and whether those conditions are causing any delays.