Camera System Aims To Keep Traffic Flowing New Technology Means Streets Don’t Have To Be Cut Up To Maintain Sensor Wires For Stoplights

New technology aimed at keeping traffic moving and saving streets from potholes and patches is watching Spokane’s drivers.

The video detection systems consist of video cameras that detect cars approaching and signal traffic lights to change colors to keep traffic flowing.

The systems are in place at seven intersections around Spokane. Council members recently approved plans to buy eight more for $222,686.

Old technology aimed at smoothing traffic flow required cutting open the streets, said Jack Sikes, city traffic systems assistant. New technology does the same job - without destroying the road surface.

“This is an emerging technology,” he said, adding that the systems have been available for only about a year.

Each system consists of four cameras - one pointed in each direction at a four-way intersection. The cameras are affixed to the metal arms that hold the traffic signals.

A camera spies a car moving toward the intersection and tells the light to stay green a little longer. It also can signal a red light to change for an oncoming car once the cross traffic has cleared.

Before the advent of video detection, the city relied on a traffic control device using electrical wires known as the “loop” system.

The wires emit high-frequency signals that change tone when cars cross over them, telling a traffic light to change.

The old systems often require cutting up streets to adjust the location of the wires, a maintenance problem that shortens the life of a street.

Video detection eliminates the need for cutting up streets. In fact, Sikes can make changes in the system from City Hall. If a camera isn’t picking up cars soon enough, he can refigure the device via computer for quicker detection.

“The whole idea is to keep traffic moving smoothly,” Sikes said. “This is another way of doing that that’s cheaper in the long run.”

The loop system still is being used throughout the city. But as dollars become available for the camera detection system, the loop will become less and less common, he said.

About 150 of the city’s 240 intersections with traffic lights employ the loop system. The balance have video detection or no timing device.

The first video detection systems on the market cost about $45,000, while loop systems cost about $30,000. Now, the cost of the new technology has dropped to about $25,000 for each four-camera set.

During a recent council briefing, Mayor John Talbott asked if the cameras can detect pedestrians and bicyclists.

That isn’t possible yet, Sikes said, adding, “This is infant technology, but maybe in the future, we can do something like that.”

, DataTimes MEMO: This sidebar appeared with the story: WHERE THEY ARE Video detection systems are being used at Garland and Market, Euclid and Market, Division and Magnesium, Division and Queen, Division and Wellesley, Addison and Wellesley, 29th and Southeast Boulevard. They soon will be online at Central and Division, Division and Francis, Division and Rowan, Ash and Five Mile, Maple and Five Mile, Barnes and Indian Trail, Indian Trail and Pacific Park, Indian Trail and Shawnee.