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

Significant closures in this round of work includes a closure of the Mount Vernon Highway bridge and ramp closures on I-285 and Ga. 400.

The main lane and road closures will happen in night and early-morning hours. Schedules may change based on the work and the weather.

I-285 lane closures

Sept. 15-16: Eastbound and westbound between Lake Forrest Drive and east of Ashford-Dunwoody Road. One right lane and one left lane closed. Hours: 8 p.m. to 6 a.m.

Sept. 18-19: Eastbound ramp to Ga. 400 northbound and southbound. One right shoulder and one left shoulder closed. Hours: 8 p.m. to 6 a.m.

I-285 ramp closures

Sept. 18-19: Westbound ramp to Ga. 400 southbound closed; traffic detoured onto Ga. 400 northbound and Abernathy Road. Hours: 9 p.m. to 5 a.m.

Ga. 400 lane closures

Sept. 15-16: Northbound and southbound between Glenridge Connector and Pitts Road. One right lane and one left lane closed. Hours: 8 p.m. to 6 a.m.

Sept. 15-17: Northbound and southbound between Hammond Drive and Abernathy Road. Two right and left lanes closed. Hours: 9 p.m. to 9 a.m.

Sept. 17-18: Northbound and southbound between Hammond Drive and Abernathy Road. Two right and left lanes closed. Hours: 9 p.m. to 5 a.m.

Sept. 18-20: Northbound and southbound between Hammond Drive and Abernathy Road. Two left lanes closed. Hours: 9 p.m. to 5 a.m.

Ga. 400 ramp closures

Sept. 20-21: Southbound ramp to I-285 eastbound closed; traffic detoured to Glenridge Connector and Ga. 400 northbound. Hours: 9 p.m. to 5 a.m.

Mount Vernon Highway road closure

Sept. 16-17: Closed between Peachtree Dunwoody Road and Barfield Road; detours onto both streets depending on travel direction. Hours: 9 p.m. to 5 a.m.

Peachtree-Dunwoody Road lane closures

Sept. 19-20: Southbound under I-285. One right lane, right shoulder, one center lane and left shoulder closed. Hours: 8 p.m. to 6 a.m.

Other traffic changes

I-285 eastbound and westbound ramps 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.

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.