LILBURN - The stop-and-go on Interstate 85 on-ramps will become more structured later this year, as ramp meters - the red and green lights that indicate when to merge - are added in Gwinnett from Jimmy Carter Boulevard to Pleasant Hill Road.
The Georgia Department of Transportation is spending $1.5 million to put the lights on entrance ramps from Cheshire Bridge Road in DeKalb County to Pleasant Hill, spokeswoman Crystal Paulk-Buchanan said. Ramp meters are also being added on Interstates 75, 285 and 20 throughout metro Atlanta.
Paulk-Buchanan said controlling merging on the ramps will make getting on the highway safer for drivers.
"The idea is that traffic will back up on the ramp, not on the interstate," she said. "There's room after you get past it to accelerate and merge into the lane."
The boxy structures are already up on Jimmy Carter Boulevard, Indian Trail Road, Beaver Ruin Road, Steve Reynolds Boulevard and Pleasant Hill Road. The devices are on each side of an on-ramp, a rectangle with a circle on either side - one that will turn green when a car can go and another that will be red when it should stop.
They should function 24 hours a day, Paulk-Buchanan said.
Brian Allen, the county's director of transportation, said DOT officials have assured him that traffic will back up on the ramps, not on Gwinnett's surface streets. He said the ramp meters have been successful in other parts of Atlanta and that almost every ramp in Los Angeles has a similar device.
But Allen cautioned that I-85 has more issues than can be solved by regulating entrances.
"It's certainly not a cure-all," he said. "It's one tool in the box."
The ramp meters, which should be functional by the end of the year, will stagger vehicle entrances to keep traffic moving. Allen said he expects an adjustment period while drivers get used to the new devices.
Eventually, Paulk-Buchanan said, even more will be added throughout the region.
Chuck Warbington, the executive director of the Gwinnett Village Community Improvement District, said he was surprised to learn that the ramp meters would be coming to I-85. When he looked up the devices, he found a study from Minnesota that said they reduce congestion between 9 and 10 percent.
Warbington said when he encountered the meters as a driver, he was initially apprehensive of them. But as he read more, he became convinced that they are effective where they have been installed.
Allen said even if traffic moves more smoothly because of the devices, it will likely continue to back up during rush hours.
"We hope it will be successful, but success is a relative term," he said. "There's so much volume, it doesn't solve the problem by itself."