SR 400 Flex Lane Will Close in December
The Georgia Department of Transportation will permanently close the northbound flex lane on December 13, 2026.
Updated on Oct. 14, 2026 in Openings & Closings
Live Poll
Do you feel local road construction projects are making travel in your community easier?
Beginning December 13, 2026, the Georgia Department of Transportation will permanently close the northbound flex lane on State Route 400. This closure is necessary to facilitate ongoing construction for the State Route 400 express lanes project.
Why it matters
The closure allows construction crews to proceed with the major express lanes infrastructure project. Drivers in Alpharetta should expect work zones and barrier installation as the project advances.
Four northbound travel lanes will remain open to traffic following the closure. The impacted zone is located approximately one to two miles south of the Forsyth County line.
The players
Georgia Department of Transportation
This state agency is responsible for the planning, construction, and maintenance of the state's transportation infrastructure.
The details
Crews will install a temporary concrete barrier wall to facilitate the transition as the flex lane ceases its role as a peak-hour travel lane. Access to the Exit 11 Windward Parkway off-ramp will remain open throughout the transition.
Timeline
December 13, 2026: The permanent closure of the State Route 400 flex lane takes effect.
Market Landscape
The closure represents a shift in regional transit infrastructure as the State Route 400 express lanes project progresses. This adjustment aligns the roadway configuration with long-term capacity goals for the corridor.
Commuters should anticipate changes to their daily drive as the flex lane is removed as a travel option. Access to Exit 11 will remain operational, though drivers should prepare for construction activity in the area.
The takeaway
Drivers in Alpharetta should plan for reduced lane capacity on northbound State Route 400 starting in mid-December. Adjusting travel routines now can help mitigate potential delays caused by the upcoming barrier installation.
Further reading
For more information on local road changes, see Alpharetta Openings & Closings.
More information
Find project updates and maps on the GDOT express lanes project website.
Live Poll
Do you feel local road construction projects are making travel in your community easier?
