The State Transportation Board Thursday approved plans to overhaul the interchange of interstates 285 and 20. Credit: GDOT

ATLANTA – The State Transportation Board gave the green light Thursday to a planned overhaul of the interchange at interstates 285 and 20 in DeKalb County.

The project, expected to cost $350 million to $450 million, will include reconstructing three ramps, adding new collector-distributor and auxiliary lanes and replacing several bridges, Meg Pirkle, chief engineer for the Georgia Department of Transportation, told board members before Thursday’s vote authorizing the work.

The often congested interchange on the east side of metro Atlanta’s Perimeter Highway is ranked as the nation’s 25th-worst highway bottleneck, Pirkle said.

The project will be built on a design-build-finance model, the same that was used to build the Northwest Corridor toll lanes project in Cobb and Cherokee counties, and in the redesign of the I-285/Georgia 400 interchange, a project that is still under construction.

Under a resolution the State Transportation Board adopted Thursday, the DOT will manage the project. The State Road and Tollway Authority will enter into a contract with a road-building company and private-sector consultants to design, construct and finance the work.

The project timetable calls for the DOT to issue a request for qualifications this summer and select a short list of finalists in October. Two requests for proposals will follow in November and January, with the contract to be awarded during the third quarter of next year.

Construction is due to begin in 2022, and the new interchange is scheduled to open to traffic in 2025.

In other business Thursday, Georgia Commissioner of Transportation Russell McMurry reported that traffic around the state is starting to pick up after falling off dramatically during the initial weeks after the state’s economy was shut down in response to the coronavirus pandemic

At the low point early last month, traffic on the state’s highways was down 40% to 50% on average, McMurry said. It has rebounded since then and is now 25% to 30% below pre-pandemic levels, he said.

“It’s an indicator of what the economy is doing,” McMurry said.

McMurry said truck traffic in Georgia only fell off 10% to 20% at the height of the lockdown and is now back to normal.