Understanding the gridlock: WECT talks to Wilmington traffic light engineer

Understanding the gridlock: WECT talks to Wilmington traffic light engineer

WILMINGTON, N.C. (WECT) - Traffic is routinely listed as one of the most important issues for Wilmington voters. Anyone who has spent time driving around the Port City knows about the often aggravating amount of time spent stuck at red lights. When traffic is moving, it’s often impossible to travel the posted speed limit because of all the congestion on the roads.

WECT sat down with Denys Vielkanowitz, the Signal Systems Management Engineer for the City of Wilmington to learn more about this topic of great interest to our viewers. He’s tasked with managing the city’s traffic lights.

“We take pretty great pride in having a coordination through the city. A lot of people would disagree that it works well,” Vielkanowitz joked about regular complaints he hears from drivers who feel they are excessively delayed by the gridlock on some of Wilmington’s busiest roads.

Too many cars, not enough road

Vielkanowitz says there are two main reasons traffic here doesn’t flow more freely. The biggest one is traffic volume.

“Only so many cars can go across a point in the road in an hour. And we are getting to the point where there are more cars that want to go across the single point in the road in one hour then we have lanes to handle that,” he explained, saying that adding turn lanes and through lanes in some of the most congested parts of town could definitely alleviate delays.

There are major road improvements planned, including intersection upgrades to interchanges at two of the city’s busiest intersections: Military Cutoff Road & Eastwood Road, and Market Street & Eastwood Road/Martin Luther King Parkway. Still, those upgrades are years away from completion, and the influx of people continuing to move to Southeastern North Carolina show no signs of stopping.

“Every family that moves down is going to bring two or three - or however big a family is - four cars with them, and they’re going to be on the roads every day,” Vielkanowitz noted of the unfortunate reality that congestion on our roads is likely to get worse before it gets better.

While Vielkanowitz is eager for the road improvements expected to relieve congestion at some intersections, he pointed out that in some ways, it will just shift the bottleneck down the road. What helps drivers at the corner of Military Cutoff Road and Eastwood Road, for example, may result in more backups for drivers at nearby Oleander Drive and Greenville Loop Road.

Dated technology

Vielkanowitz attributes dated technology as another reason Wilmington traffic doesn’t move more efficiently. The system currently used to coordinate traffic lights was installed in 2009. It was an upgrade from the old dial-up network for traffic lights the city previously had, but the “serial network” we have now is slower than Ethernet technology now being used in some other parts of the country. Traffic engineers can make timing tweaks to the traffic lights in a matter of seconds through Ethernet connections, rather than several minutes of delay through a serial system.

Moreover, technology on some newer systems is “traffic adaptive.” That means traffic signals actually talk to each other, making real-time adjustments to allow for heavier traffic volume as needed, and automatically coordinating with the signals further down the road to complement the changes. On the system Wilmington is using now, the traffic lights do not talk to each other. They talk to the main office, where adjustments must be entered manually and programmed for each individual traffic light.

That is a cumbersome process, and therefore rarely implemented. Vielkanowitz says in the ten years he’s worked in his position managing the traffic lights, he estimates they’ve only changed the light timing for a major accident tying up traffic a dozen times. He says once a week, they might make a minor, temporary tweak to the timing at one stop light where traffic has backed up for one reason or another. But that every change they make has a domino effect on traffic at other stoplights, so they try not to meddle with the lights more than they have to.

Vielkanowitz said despite its limitations, the current system is safe. The Department of Transportation is slated to install a replacement system to coordinate Wilmington Traffic lights in 2027, at a projected cost of $16 million. The available technology is likely to change again in the meantime.

Competing goals

Making the most of what they have to work with, traffic engineers have to make hard choices when coordinating the traffic lights. They prioritize traffic flow for some drivers at the expense of others.

For example, traffic flows more smoothly for drivers on Military Cutoff Road heading in the direction of Porters Neck. Drivers heading in the opposite direction, towards downtown, are more likely to get stuck at a stop light. Even though there is heavy traffic in both directions, Vielkanowitz says especially in the evening, more drivers are trying to leave Wilmington. So they time the lights to keep things flowing in that direction, which actually hinders the flow for people travelling into town.

While they can see a lot on the TV monitors in the River Road headquarters that show traffic at various intersections across town, every two years, traffic engineers and the Wilmington Metorpolitan Planning Organization hit the roads to do an up close analysis of the traffic on Wilmington’s most congested roadways.

“It’s definitely beneficial to be in the car and see things happen. You can see things a lot more from the field,” Vielkanowitz said. He said it’s not practical to do this all the time, but when they are out in the field, they make note of changes and tweaks that they think could make traffic move more efficiently.

As a result of their findings, last year, Wilmington traffic engineers increased the light cycle length during the morning rush hour. More cars can cycle through an intersection if it stays green in the same direction for 1 minute compared to two 30 second intervals, because of the time it takes for a line of cars to start moving.

With those tweaks completed, they are now increasing the cycle length for the lunch hour, and eventually, they will tackle the light timing during the evening rush hour. But Vielkanowitz says the longer a light stays green in one direction, the longer it is red for drivers travelling in a competing direction, so they don’t want the signal length to be longer than it needs to be during off-peak times. It’s a balancing act he says they have to tackle one step at a time.

“We are constantly chasing our tail as to what cycle length is too long, what’s too short, is traffic backing up bad on this one movement, do we need to add more southbound time? Does this left here need more time? Everybody needs more time is the problem. We can’t create time and we are not in the road building business,” Valkanowitz said of the constant challenges of the job of a signal system engineer.

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