DOT to open auxiliary lanes on southbound Ga. 400

It will be the second effort within a month to ease the traffic flow on that busy highway without major new construction.

Last month, it began allowing morning commuters to drive in the southbound shoulder lane for the five miles from Holcomb Bridge Road to the North Springs MARTA station. Previously, police and transit buses had exclusive use of the shoulder lane.

Now, the DOT plans to add another lane for through traffic from McFarland Parkway in south Forsyth County to Holcomb Bridge Road in Roswell, by opening up the lanes now reserved for drivers getting ready to exit or enter the highway. Work is scheduled to begin next week.

“By returning to a traditional entrance and exit merge format, we are able to provide motorists with more capacity and better mobility in this corridor without the cost of having to pave a new lane,” DOT Commissioner Keith Golden said.

DOT officials will not predict how much time commuters might save as a result of this latest measure, and say they do not anticipate major problems with vehicles merging.

Highway officials have said they will evaluate how successful such changes are, and have indicated they may expand the shoulder-lane project later this year to include northbound drivers.

The auxiliary lanes being opened to through traffic are the right lanes between on- and off-ramps, which were intended to give drivers a safe way to merge into traffic while preventing bottlenecks caused by drivers entering or getting off the freeway.

Crews plan to adjust signs and restripe the first section, from Haynes Bridge Road to Mansell Road, overnight Monday and have it ready for Tuesday morning traffic.

Motorists entering Ga. 400 southbound at Windward Parkway, Old Milton, Haynes Bridge Road and Mansell will immediately need to merge into through traffic.

"It will be just like if you were entering I-75 at Howell Mill," DOT spokeswoman Jill Goldberg said. "It's not going to be any different than your normal merging and exiting on an interstate."

The process will be repeated the following Monday and Tuesday, June 18 and 19, in the southbound auxiliary lanes between McFarland Parkway and Old Milton.

The result will be approximately nine more miles of a continuous-flow travel lane between McFarland and Holcomb Bridge.

The measure is the latest DOT initiative to take low-cost steps to improve traffic flow on one of metro Atlanta's busiest commuter arteries, Goldberg said.

The change involving the shoulder lanes brought a traffic nightmare the first two days but has since improved commuting times by as much as 15 minutes from Windward Parkway to Northridge Road.

Unlike the shoulder lanes farther south, the auxiliary lanes will be open 24 hours a day, every day.

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