The Traffic Maestro
Odd Jobs That Keep The Area Humming
Monday, September 4, 2006
Here is a typical e-mail waiting for Nhan Vu when he arrives at work in the morning, this one from a county official complaining on behalf of a constituent: "[A citizen] called in saying that when she is coming from Hoadley Road & then turning right onto 234 & then turning Left onto Counselor Road. This is how she goes to Woodbine Shopping Center . . . the left turning light from 234 going to Counselor is not long enough she says that only about 6 cars can turn at a time.
"She thinks that this turning light should be longer."
Vu, 33, is the operations manager at the Virginia Department of Transportation's Smart Traffic Center for Northern Virginia, a hub of computers and cameras and mathematical models used to monitor local roadways. In a region dubbed the nation's second-worst for commuters, it's the facility at the core of the chaos, and Vu is the conductor. A civil engineer, he is one of just three people who can change the timing on the area's traffic lights -- deciding how to clear a nasty backup on Leesburg Pike, for example, or whether to bestow a particular neighborhood a few extra seconds of green for the morning drive.
If there's a cosmic side to his job as master of time, he is also the target for local politicians and drivers who think their red light is the longest in the region.
"We only hear from people when there are problems," he said as he sat in front of one of a dozen computers that show, with graphics not dissimilar from video games of the Pac Man era, the lights changing from green to yellow to red at intersections in Northern Virginia. "People make it home without an incident and they don't realize it."
Located near the Pentagon, the Smart Traffic Center includes a dim room with large movie screens showing grainy images of cars chugging down the region's highways. Among other things, this is where several people type the messages that appear on those digital boards along major roads, succinct and prosaic communications such as "Accident Ahead," or "Delays from exit 66 to exit 64."
The system will allow only certain words and blocks any attempts at humor.
In the next room, Vu's small staff of traffic engineers works behind computers, one of them entering data about the number of cars that go through an intersection during peak hours. That information is compiled with other statistics to form a model that creates the timing for lights at about 1,400 locations.
Vu, who is on call around the clock, never anticipated a profession in which he would begin to habitually count the length of green lights, even on vacation. He certainly never knew he would spend his days bargaining with people, giving them an extra second here or a whopping five seconds there.
He wanted to be an FBI agent. But Vu, who fled Vietnam and came to Northern Virginia in eighth grade, was offered a scholarship to go to George Mason University for civil engineering. While there, he began to volunteer at the center. He graduated, went on for his master's and his hours at the traffic center became full-time.
Vu is fine with that. He likes overseeing the ballet of stops and gos. He likes the perfect science behind timing the lights. But he has learned, he says in his engineer-speak, that "optimization is not for everyone." People don't care, in other words, if traffic a mile away is better because they have to wait 18 extra seconds.
Many of Vu's hours are spent with people who e-mail him about their one light. He dutifully looks up the data and explains why they get only eight seconds to stream through a left-hand green.
It's not always a fun exchange. Vu may call someone back and say he can move the light by one second. "They say, 'I need 30 seconds! I pay taxes here!' " And so he goes through his statistics -- that adding 30 seconds to one person's green light means backing up dozens of cars at the red light down the road.
"They think time is something you give to them, not that you're taking it from someone else," he said.
What bothers him are the limitations. He may know that an intersection is backed up, but he can't always do anything about it. Like at Route 123 and the Beltway. "We know traffic wants to get out," he said, "but timing is not going to help."
In response to that Route 234 e-mail, Vu found that it was, in fact, "running a very short cycle length." First, he explained to the citizen the "advantages and disadvantages of short cycle lengths."
In the end, VDOT staff reviewed the timing and made a generous recommendation: an additional five seconds for a left turn. There is a new housing development nearby, Vu found, so there are more cars trying to get through.
It may not be the FBI, but the job has its satisfactions.
"I wanted to help people," he said with a shrug.