Signal re-timing improves flow on Virginia Beach roads

By Liz King

Next time you travel down Independence Boulevard and are so excited because you’re hitting green light after green light – know that it’s not pure luck.

A new synchronized traffic-signal system on eight roads is reducing travel times, Virginia Beach officials said.

Rather than each signal depending on its own sensors, the new system allows green lights along a road to occur sequentially whenever possible, smoothing traffic flow.

“We have gotten good amounts of feedback,” said Frank Hickman, manager of Traffic Operations. “Someone called to tell us that his travel time to work has been reduced by five minutes.”

According to city traffic engineers, during the past year, delays were reduced 27.3 percent on Northampton Boulevard, 25.4 percent on North Independence Boulevard and 23.7 percent on Great Neck Road – among other streets.

Virginia Beach has nearly 400 traffic signals. The city’s Traffic Management Center oversees them using a network of 100 miles of fiber optic cable and 40 closed-circuit television cameras, according to Drew Lankford, public works spokesman.

Traffic signal re-timing began in fall 2008, after the city hired private consultants to study traffic delays, Hickman said.

“The goal was to find the optimal cycle length for drivers to get from point A to point B,” Hickman said.

For the study, the city focused on 260 heavy traffic corridors in the city.

Workers drove the corridors at different times of the day and recorded travel times, tracked turns at intersections and conducted traffic counts, Hickman said. Researchers then used software to model the traffic flow and to develop synchronized signal timing.

“Typically, there was a 15 percent reduction in delay,” Hickman said, noting that signals’ cycle lengths are based on the posted speed, so someone driving significantly slower or faster than the speed limit may hit red lights more often.

Because the initiative will reduce stops and vehicle idling, and decrease fuel emissions, it qualified for a $1.2 million federal grant from the Metropolitan Planning Organization, a regional planning agency made up of local officials and transportation experts. The city also received $500,000 from Congress.

“Most cities don’t typically re-time signals more often than every 10 years or whenever they have the money for it,” Hickman said.

To date, more than 250 traffic signals have been re-timed, and the city is adding 20 signals to the network next year, Hickman said.

With the help of a new $2.2 million grant from the MPO, Hickman hopes to re-visit some of the signals that were re-timed at the start of the study in 2008. Traffic patterns may have changed because of developments.

“The city is growing,” Hickman said. “And you can’t build your way out of congestion. Our goal is to increase efficiency with the electronics we have in place. This has been a good program, and we want to keep it up the best we can.”