From a Metro press release:
Red Line Track MaintenanceDefinitely tune in to the Red Line Twitter feed Monday to find out all about it. Here's the full release.
Metrorail customers traveling between the Silver Spring and Forest Glen Metrorail stations should add at least 20 minutes of travel time for their trips because personnel will replace rail fasteners that stabilize the rail tracks. Trains will share one track between these locations from 8 p.m., Friday, February 20, to closing (midnight), on Sunday, February 22.
Nice piece on GGW about Metro's budget woes.