The Georgia Department of Transportation has announced the latest round of lane closures and other traffic changes for Transform 285/400, its massive project to reconstruct the I-285/Ga. 400 interchange.

The lane closures affect two surface streets in Sandy Springs: Glenridge Drive and Mount Vernon Highway. The closures affect a single lane and happen only in night and early morning hours: 8 p.m. to 6 a.m.

Other changes, affecting Ga. 400 flex lanes and I-285’s westbound ramp to 400, will happen during the day, 7 a.m. to 7 p.m. Schedules may change based on the work and the weather.

Mount Vernon Highway lane closures

July 31-Aug. 4: Westbound between Peachtree-Dunwoody Road and Barfield Road. Hours: 8 p.m. to 6 a.m.

Glenridge Drive lane closures

Aug. 1-2: Northbound between Glenforest Road and Johnson Ferry Road. Hours: 8 p.m. to 6 a.m.

Other traffic changes

Ga. 400 flex lanes — where the shoulder of the road is used as an extra travel lane during commuting hours — will be closed intermittently daily between Pitts Road and the North Springs MARTA Station ramp. That is for tree-clearing and utility relocation work. Hours: 7 a.m. to 7 p.m.

I-285 westbound ramp to Ga. 400 will have intermittent “traffic pacing,” meaning that police cars will force other vehicles to temporarily slow or stop. That is for tree-clearing and landscape preparation. Hours: 7 a.m. to 7 p.m.