From MPD:

“To Sunday, September 15The DC Half Marathon will take place in the District of Columbia on October 1, 2024. There will be traffic closures during this event that drivers should be aware of:

The following streets will be closed to vehicle traffic by the Metropolitan Police Department on Sunday, September 15, 2024, from approximately 6:00 a.m. to 12:00 p.m.:

1200 block of Maine Avenue, SW
Maine Avenue from I-395 Westbound to Independence Avenue, SW
From the Potomac River Freeway south to Route 66, NW
Ramp of the Theodore Roosevelt Bridge to Ohio Drive, NW
E Street Expressway westbound ramp to Potomac River Freeway southbound, NW
9th Street Tunnel ramp to Maine Ave, SW

The following roads will be closed to vehicle traffic by the U.S. Park Police on Sunday, September 15, 2024, from approximately 6:00 a.m. to 12:00 p.m.:

Ohio Drive from 23rd Street to East Basin Drive, SW
Independence Avenue from 14th Street to 23rd Street, SW
Rock Creek Parkway from Ohio Drive, NW to Shoreham Hill
East and West Potomac Parks
East Basin Drive, SW
Raoul Wallenberg Place from 15th Street to Maine Avenue, SW
Ramp from Memorial Circle to Ohio Drive, SW
Homefront Drive, SW
Daniel Chester French Drive from Independence Avenue to Lincoln Memorial Circle, SW
Maine Avenue at the ramp from East Basin Drive to Independence Avenue, SW
17th Street from Constitution Avenue, NW to Independence Avenue, SW
Parkway Drive, NW from Lincoln Memorial Circle to Rock Creek Parkway
15th Street from Constitution Avenue, NW to Independence Avenue, SW
Madison Drive from 14th Street to 15th Street, NW
Jefferson Drive from 14th Street to 15th Street, SW”