Ill-timed stoplights add to driving woes
Idleness is a drag when gas is hovering around $4 per gallon. One way to increase gas mileage is to reduce idling, and one place people spend a lot of time idling is at stoplights. According to a 2007 study by the National Transportation Operatio...
Idleness is a drag when gas is hovering around $4 per gallon.
One way to increase gas mileage is to reduce idling, and one place people spend a lot of time idling is at stoplights. According to a 2007 study by the National Transportation Operations Coalition, out-of-sync traffic lights require the average household to fill their tanks five more times than they normally would every year.
The News Tribune asked its online readers to nominate the best and worst stoplights in Duluth. Stoplights on two downtown one-ways, Second Street and Third Street, got rave reviews, while intersections on Miller Trunk Highway from Central High School to the airport were the most maligned.
Part of the problem is the stoplights on Miller Trunk haven't been retimed in about 20 years, highway officials say, and they won't be updated for a few more years.
Tamara Jones of Duluth said she spends three or four minutes each day waiting at stoplights in the city, especially those on 12th Avenue East from Fourth Street to Superior Street. She said she didn't know how much extra money she is spending at the pump because of the idle time, but said her 1988 Volvo Wagon doesn't do well with the frequent stops and starts of in-town driving.
"As soon as one turns green, the next turns red," Jones said. "You get all itchy like you should just go, and you can't."
The city of Duluth is responsible for timing all stoplights within the city limits that aren't on state or county roads. Downtown stoplights were retimed in January for the first time in about 20 years, said Cari Pedersen, the city's chief engineer of transportation.
"One-ways are generally much easier to set and actually have them progress through the system," Pedersen said. "It's just the way things work -- you can't have green in both directions. That's some of the issues that Miller Trunk's going through. With heavy volumes in both directions, somebody's going to get a red."
Pedersen said her department rarely, if ever, gets complaints about stoplight timers.
Miller Trunk, however, is another story. It's a state road, so the Minnesota Department of Transportation is responsible for timing its stoplights. John Hoivick, district signals and lighting supervisor for MnDOT, said the lights are timed according to the time of day and the traffic direction, but the timing hasn't been updated in about two decades.
"For the a.m. peak, the bulk of the traffic is inbound, so we try to time it so there's a progression inbound -- one turns green, then the next turns green -- to the sacrifice of the opposing direction," Hoivick said.
"If you talk to anyone who drives that stretch, it doesn't always work that well."
You can say that again. Our online readers registered far more complaints -- and far more frustration -- about the Miller Trunk corridor than any other stretch of road in town.
Unfortunately, the stoplights on Miller Trunk won't be retimed again until a $21 million project to improve traffic flow in the mall area is completed, Hoivick said.
"The construction starts this fall, and once that job is completed and traffic has settled into normal traffic patterns [we can do the study]," Hoivick said. "Before would just be a wasted effort."
To do the study, MnDOT staffers will count traffic at various times of the day and week, with a bigger sample producing a more realistic model. Once a model is developed that accurately reflects what traffic on the corridor looks like, traffic engineers can develop timing plans.
"Then you play with the variables and try to get them to match what we're seeing on the road," Hoivick said. "The real challenge is getting the data -- it takes a lot of person-hours to accumulate the data -- and then you have to come back and find someone who really knows how to work the model. The model means nothing unless it matches reality."
Until then, University of Minnesota Duluth mechanical engineering professor Dan Pope advises that drivers stuck in long intersections turn off their engines to save gas.
"Back with carbureted vehicles, starting them was a huge consumption of fuel," Pope said. "With most cars today there's no difference with starting and restarting it. ... If you get bridged, turn off your car. If you get stuck behind a train, turn it off."