Metro is no longer single-tracking on the Green Line following earlier track repairs a brief shutdown between U Street and Fort Totten.

Update: Feb. 16, 12:09 p.m. Metro is no longer single-tracking on the Green Line following earlier track repairs and a brief shutdown between U Street and Fort Totten.

Update: Feb. 16, 10:38 a.m. Metro is now single-tracking on the Green Line after a 30-minute shutdown between U Street and Fort Totten and earlier track repairs.

Update: Feb. 16, 9:58 a.m.: Metro is shutting down the Green Line from U Street to Fort Totten for about 30 minutes. After the shutdown, Metro said it expects to restore service following earlier rush-hour repairs and single-tracking. Metro notified riders of the shutdown at 9:52 a.m.

WASHINGTON – Green Line riders faced major disruptions Friday morning as Metro tried to fix problems with the tracks near Columbia Heights. But Metro said the work was expected to wrap up by the afternoon rush hour.

Work to replace about 100 feet of rail began Thursday night.

Metro announced the repairs Feb. 14 and said temporary measures were in place to allow trains to continue to run through the area before the work got started.

Metro’s ultrasonic testing detected a possible defect in the rail. A rail problem that was undetected contributed to the Red Line derailment between Farragut North and Metro Center last month.

Service changes

Green Line trains will single-track between U Street and Georgia Avenue-Petworth until whenever the work is completed.

Single-tracking means a significant reduction in the number of trains running on the Green Line. During the single-tracking, Yellow Line trains will run between Huntington and Mt. Vernon Square.

Metro is urging riders Friday to use the Red Line, the bus lines along 14th Street, 16th Street and Georgia Avenue, or MARC trains between Greenbelt, College Park and Union Station. From Southern Maryland, commuters can consider MTA commuter buses.