Ashford-Dunwoody Bridge Closed While Crews Build “Diverging Diamond”

It’s been tried in Europe and other U.S. cities, but never in Georgia until now. Transportation crews will close the bridge on Ashford Dunwoody Road over I-285 this weekend to construct a “diverging diamond” interchange. The concept shifts the flow of traffic to the opposite side of the road to keep things moving. Georgia Department of Transportation spokesman Mark McKinnon says the new design will make it easier to enter 285 from busy Ashford-Dunwoody.

“You actually will cross over onto the opposite side of the road you normally would cross on,” he explains, “You think of European countries that travel on the left side of the road, well, that’s sort of what you’ll be doing as you cross that bridge.”

McKinnon says that “crossover” will be brief.

“That allows you to make an unimpeded left turn on I-285,” he says, “And, as you get to the opposite end of the bridge, if you are not getting on I-285, you will cross back over into the right lane.”

McKinnon says there will, of course, be a learning curve. The bridge on Ashford-Dunwoody will close at 9 p.m. Friday and will reopen at 5 a.m. Monday. During that time, the pedestrian walkway on the bridge will also be closed. McKinnon suggests using MARTA instead.

Drivers will be able to use the new lanes Monday, but construction will continue into the fall.

GDOT is banking on the project being a success. McKinnon says two more “diverging diamonds” are planned for intersections on I-85, at Jimmy Carter Blvd. and Pleasant Hill Rd.

To see a simulation, click here.