The state’s “Transform 285/400” project is finally truly transforming the I-285 and Ga. 400 interchange in Perimeter Center, as bridges for new ramps begin to tower over the existing knot of surface highways.

“The main push right now is the largest and highest bridge,” said Marlo Clowers, the Georgia Department of Transportation’s Transform 285/400 project manager, in a recent interview.

Pillars going up in the interchange in July. (Phil Mosier)

That’s the bridge that will carry a new ramp connecting Ga. 400 southbound to I-285 eastbound. Pillars are going up for that bridge as well as for other ramps and so-called collector-distributor lanes that will let traffic bypass some of the currently tricky merging spots.

Transform 285/400 is intended to rearrange the interchange to improve the flow of existing traffic and make it safer by reducing merges.

Work on the interchange project began in 2017 and currently has a “substantial” completion date of Oct. 15, 2020, said Clowers. Finishing work could continue into 2021.

Besides the major work in the heart of the interchange, smaller but significant work has begun on other elevated ramps and lanes. Pillars are going up in Dunwoody at the Ashford-Dunwoody Road ramp onto I-285 westbound, where “braided” lanes will carry traffic over and into the regular flow.

One of the pillars that will carry new lanes at the Ashford-Dunwoody Road entrance ramp to I-285 westbound. (Phil Mosier)

A similar ramp will be installed from Sandy Springs’ Roswell Road onto I-285 eastbound, a frequent pinch point for traffic exiting to Ga. 400. Today’s surface-level Roswell Road entrance ramp will become elevated onto pillars. “It’s not a roller coaster,” says Clowers, but it will take traffic up and over the merging mess.

With similar ideas in mind, the project eventually will change another pinch point: the Glenridge Drive entrance ramp to I-285 westbound, which is less than a half-mile from the Roswell Road exit ramp and frequently used as a busy shortcut. In the final project, the Glenridge entrance ramp will remain, but traffic will be walled into a collector-distributor lane and unable to exit to Roswell Road, eliminating the short-cut and its effects on traffic merges.

An illustration of what the I-285/Ga. 400 interchange is intended to look like after the project’s completion. (GDOT)

The following photos of the project were taken in July. For the latest updates on lane and ramp closures for the Transform 285/400 work, see our story here. For more about the project, see GDOT’s website.

John Ruch

John Ruch is an Atlanta-based journalist. Previously, he was Managing Editor of Reporter Newspapers.