The latest updates and news on Transform 285/400 and its transportation impacts in Perimeter

Under Construction: Transform 285/400

Led by the Georgia Department of Transportation, the I-285 at GA 400 interchange is undergoing a major upgrade over a multi-year coordinated construction period that will add roadway capacity, improve traffic flow, safety and access, and generate opportunity for new investment in the Perimeter area. Construction for the project is scheduled for completion in 2023.

24/7 Lane Closures on I-285 Begin Early October

The Transform 285/400 transportation project will soon enter its most transformative stage. To complete construction of the 285/400 improvements and replace a series of 50-year-old bridges along I-285, the Georgia Department of Transportation (GDOT) will close two left-hand lanes in each direction of I-285, between Roswell Road and Ashford Dunwoody Road. This closure is slated to begin as early as Saturday, Oct. 8 and will last until the project’s completion sometime in the second half of 2023. Parallel collector-distributor lanes being built as part of the Transform project should help to absorb some of this disruption and smooth merging in the area. Once completed, the 285/400 interchange will be able to handle more vehicles with less delay, providing a better experience for those coming to Perimeter or passing through on I-285 or GA-400.
Lane closure start: GDOT has set a tentative start date of Saturday, Oct. 8, 2022

Lane closure completion: Currently projected for latter half of 2023

Where? Two interior lanes will be closed first; closed lanes will shift as work shifts to next segments of the bridge replacements.

When? Lanes will be closed 24/7 to allow disassembly and replacement of the existing bridge structures

Why are they doing this? I-285 is 50 years old, and the bridge sections are due for replacement to ensure their safety. This work has been included in the 285/400 reconstruction to save money and reduce construction impacts on the community

For detailed project issues, concerns, or questions please contact the Georgia Department of Transportation directly at
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Transform 285/400 BY THE NUMBERS

10.5 MILES

includes 4.3 miles of upgrades on I-285, from Roswell Road to Ashford Dunwoody Road, and 6.2 miles on GA 400, from Glenridge Connector to Spalding Drive.


The project kicked off in February 2017 and is expected to be completed in 2024.


in construction upgrades to improve travel conditions and access on the interchange.

20,000 HOURS

Improvements are estimated to save GA 400 and I-285 travelers this total amount each day.