Turning left will never be the same: GDOT to open new interchange in DeKalb

“It’s a little different,” GDOT Commissioner Russell McMurry said Thursday.

McMurry described it as an innovative way to deal with one of the hardest maneuvers a driver can make — turning left. Those turns require crossing oncoming traffic, one of the most common crash scenarios.

At a busy intersection like this one, near the new Arthur M. Blank Children’s Hospital, that can put thousands of commuters at risk of collisions daily. GDOT estimates an average of nearly 50,000 vehicles pass through the intersection from the hospital side of the interchange daily.

In an intersection with a displaced left turn, vehicles are funneled left into their own lane that completely bypasses oncoming traffic.

Credit: Georgia Department of Transportation

Credit: Georgia Department of Transportation

At this intersection, a lane parallel to the bridge over I-85 has been built to handle the traffic turning left onto I-85 from North Druid Hills Road.

Coming from the hospital, left-turning drivers will get in that lane while other traffic continues on North Druid Hills Road.

Drivers are likely more familiar with diverging diamonds, which were first introduced in the metro area in the early 2010s when Ashford-Dunwoody Road over I-285 was rebuilt. Roundabouts are another way of simplifying left turns.

But at North Druid Hills Road and I-85, the displaced left turn made the most sense, GDOT spokesperson Kyle Collins said. A diverging diamond would have cost more and required the construction of new bridges, he said. At the same time, it wouldn’t have significantly increased capacity.

This project costs about $100 million and includes a series of changes in addition to the displaced left. Parts were completed last year and other parts are under construction still, including a ramp onto the I-85 service road.

GDOT put a displaced left turn on only the hospital side of the intersection, because that is where the bulk of the traffic originates. Adding it to both directions would have required significantly more right of way, Collins said.

GDOT is using displaced left turns in a few of its newer projects.

There is one in Dawson County and another in Gwinnett County at the intersection of U.S. Route 78 and Scenic Highway. Others are planned for Douglas and Fayette counties.

If the weather cooperates, GDOT will open the new displaced left turn on North Druid Hills Road on Saturday.

Credit: Miguel Martinez-Jimenez

Credit: Miguel Martinez-Jimenez