Living in a major city often means regular growth in population, urban density, significant dependence on automobiles, and traffic congestion. Besides being an absolute pain for drivers, traffic congestion makes our roads less efficient, increases travel time, air pollution, and fuel consumption. We look for ways to combat traffic and improve traffic flow throughout the city. One way we do this is Intelligent Transportation Systems (ITS) technology. ITS technology is available in several forms, which you have no doubt noticed around Seattle. From countdown pedestrian signals to dynamic message signs that give drivers important information on traffic conditions ahead, ITS is providing ways to improve safety, travel time, and reduce fuel consumption.
Currently SDOT has about 55 of Closed Circuit Television (CCTV) cameras installed throughout the city. You can find up-to-the-minute still images on our Traveler’s Information Map. Camera operators use the images to look for incidents that may be blocking roadways so that travelers can be informed via the Traveler’s Information Map, dynamic message signs, or Twitter. By providing this real time information, drivers are able to make more informed decisions on how they commute to their destination. We plan to double the number of these cameras by early 2010.
One of the newest ITS technologies we’ve used in Seattle is a license plate reader camera. These cameras use CCTV technology to scan license plate numbers to measure the travel time along a defined space or corridor. To track a vehicle’s travel time, we set up an entry point and an exit point. Once a vehicle enters the entry point, their license plate number is recorded, and if they reach the exit point, their license plate number will be recorded again. As multiple vehicles pass through this defined space, their travel times will be averaged to create an accurate picture of current travel times. This travel time information can then be shared with the public. All license plate data is discarded once the travel time information has been recorded.
One more way we are keeping Seattle moving!