A southbound lane of the 9th Street tunnel in downtown D.C. will be closed for nine months starting Monday as crews work on repairs.
The long-term closures start near Constitution Avenue NW and continue beneath the National Mall through June 30 next year.
One outer lane will be closed 24/7 and the center lane could close for up to six hours during non-peak hours as needed. If the center lane closes, there will be just one lane open to traffic…