Commuting through Cherokee and Cobb counties may become less stressful by 2013.

To relieve traffic congestion, the Georgia Department of Transportation plans to add reversible lanes on sections of interstates in both counties.

If the lanes become reality, which is expected, construction could start next summer and take three years to complete, said Earl Mahfuz, Public Private Partnership program director for the GDOT.

Mahfuz presented Cobb leaders with a fast-track plan to add the reversible lanes to Interstates 75, 575, 285 and 20 during the county government's annual retreat at Lake Lanier Islands Resort.

The reversible lanes would mitigate rush-hour traffic by changing direction to meet demand. Drivers will be able to merge onto the lanes at limited access points along the interstate. When lanes change directions, access points to enter the lanes in the opposite direction would be barricaded.

The lanes would be high-occupancy vehicle/ high-occupancy toll, and riders would be required to place a small scanner in the upper corners of their windshields. Sensors would be set up to track the mileage of the cars riding in the new lanes.

Cars with three or more passengers would turn the scanners off and ride in the lanes free of charge. Those with fewer than three would turn the scanners on and be charged a fee per mile, which would be displayed at the access points so drivers can know ahead of time what they will be charged.

"This is huge," Cobb County Commission Chairman Sam Olens said. "There has been talk, but I am confident things will finally happen. The project grew to a $4 billion plan, but has been cut back drastically so it's feasible, and looks like it's going to forward and will happen."

The GDOT is looking at two separate projects.

The first, which is expected to cost about $1.1 billion, would create two reversible HOV/HOT lanes in between the existing north and south lanes on I-75 between I-285 and I-575. Once the new lanes reach I-575, they split.

One lane is proposed to continue up I-75 to Hickory Grove Road near Acworth and another would continue up I-575 to exit 11 at Sixes Road in Cherokee. Access points are proposed along I-75 at Terrell Mill Road, Roswell Road, the Big Shanty Connector and Hickory Grove Road. Points along I-575 are proposed at Big Shanty Road, Shallowford Road, Dupree Road and Sixes Road.

Since the lanes are reversible, Olens said they will open to cars driving south in the mornings and to those traveling north in the afternoons.

Mahfuz said traffic issues during construction will be minimal to nonexistent as they are being constructed in between the existing north and south lanes.

The second project, expected to cost $900 million, will add lanes along I-285 and I-20. They are planned to be constructed almost simultaneously with the I-75 and I-575 project.

The second project includes two reversible lanes along I-285 between I-75 North and I-20 West and along I-20 West between I-285 and Highway 6. Access points are proposed along I-285 at Cumberland Boulevard, Mt. Wilkinson Parkway, Orchard Road and south of Bolton Road, while points along I-20 West are proposed at the Chattahoochee River, Factory Shoals Road and Highway 6.

A similar project along Georgia 400 also is being considered by the GDOT, Mahfuz said.

"The idea is to connect all the dots," Mahfuz said. "And to keep the projects within six months of each other in closings. And, once everything is completed, you can start looking at other tier levels for this, possibly for a light rail system to develop within those lanes."