Metro’s unnamed contractor will continue to perform work to reduce a prime source of delays on the Red Line Saturday and Sunday, requiring single-tracking and reduced service.
Metro officials said in a news release Red Line trains are scheduled to operate every 15 minutes and will single-track between Grosvenor and Medical Center stations Saturday and Sunday so the contractor can test a form of grouting to prevent leaks in underground tunnels.
Metro General Manager Paul Wiedefeld said Oct. 5 officials were extending the pilot project in which a contractor is testing the method of making Metro tunnels less prone to leaks. Metro formed an agreement with the unnamed company that will apply the special grout, through a process called curtain grouting, to the tunnels.
Wiedefeld has said the cause of the leaking in the tunnels between Medical Center and Farragut North is because they are located below the water table.
The contractor’s work for that project negatively impacted service in July and August, the Sentinel reported. The extension adds less than a mile to the project. Wiedefeld said the additional section of track on which the contractor is testing the waterproofing covers only a fraction of the 9-mile stretch of track in longstanding need of protection against leaks.
“This is again just very small, it’s in the range of 4,000 feet,” Wiedefeld told reporters Oct. 5. “It’s not very much.”
A week from Saturday, buses will replace trains between Grosvenor and Medical Center Station both Saturday and Sunday. The area of the shutdown includes a crossover, which Metro officials have said is required for trains to be able to single-track.
Water leaking into tunnels can cause arcing insulators – or instances in which electricity arcs and can cause smoke – which often leads to delays in service, Metro officials have said. 75 percent of arcing insulators occur on the segment of Red Line track between Medical Center and Farragut North.
Trains which are currently operating every 25 minutes on the Red Line on weeknights after 9 p.m. is due to the leak mitigation pilot on the Red Line. Trains will continue to single-track on weeknights after 9 p.m. through Nov. 24, Metro officials have said.
Reports from Metro personnel of arcing insulators, and of other electrical arcing incidents, have led Metro management to temporarily shut down the nearby stations, sometimes for hours, for investigation and for fire and rescue response, if applicable.