Anyone who’s braved the traffic hellscape recently that is Interstate 285 at Ga. Highway 400 during peak hours knows the days of vacant pandemic expressways are behind us.

But relief for car commuters should be on the way sooner than later, according to the Georgia Department of Transportation.

GDOT officials tell the AJC the $800-million addition of flyover ramps and collector-distributor lanes where two of Atlanta’s busiest highways meet should be finished by the end of 2021, with some paving work possibly spilling into next spring.

Construction began in late 2017 to help ease one of the metro’s worst bottlenecks, where the freeways overlap and feed rapidly growing Perimeter cities such as Sandy Springs and Dunwoody.

View of progress in April, looking south, from above the MARTA North Springs Station. Courtesy of Georgia Department of Transportation

The GDOT project also includes the reconstruction of traffic pinch points in the area: a new bridge at Mount Vernon Highway, and a diverging-diamond interchange where Abernathy Road meets Ga. Highway 400.

The scope of the interchange work has expanded more recently to include new bridges over Peachtree Dunwoody Road and Glenridge Drive, plus bike and pedestrian trails that will eventually serve as PATH400 connecting points, as the newspaper points out.

Those additions to the “Transform 285/400” initiative bumped back an opening that had initially been planned for last summer.

Some new ramps should start opening this summer, but remaining work will require lane closures that will cause major traffic snarls, GDOT reports.

The reimagined interchange, per GDOT's calculations, will be nearly as big as Spaghetti Junction when complete. 

In April, a view of new lanes next to I-285 eastbound, over Peachtree Dunwoody Road. This bridged section of I-285 is set to be replaced soon. Courtesy of Georgia Department of Transportation

Looking north toward Alpharetta, how the finished interchange and ancillary projects should function by year's end, per GDOT. Courtesy of Georgia Department of Transportation

Beyond the infamous interchange, GDOT is planning a billion-dollar addition of about 16 miles of express lanes up Ga. Highway 400 as part of the agency’s Major Mobility Investment Program, which will also see express lanes installed on Interstate 285.

Ga. Highway 400 plans call for four new express lanes—two heading north, the others south. MARTA, meanwhile, is drafting plans and speaking with government leaders about how best to implement bus rapid transit services—with up to five stations—within those lanes.

• Images: State Farm's massive, MARTA-connected project is nearly finished (Urbanize Atlanta)