The Red Line tunnel waterproofing effort that was supposed to come in 2016 is now scheduled for 2017 and may change again depending on when the state of Maryland and a private concessionaire are ready to build the Bethesda Purple Line station.
Last year Metro said it would shut down the Red Line between Friendship Heights and Grosvenor over 14 weekends in the summer and fall of 2016 in order to place a new precast concrete arch in the tunnel to prevent leaks that have plagued the system for years.
Last week Washington Metropolitan Area Transit Authority Deputy General Manager Rob Troup said that work is now scheduled for two periods of seven consecutive weekends in the fall and summer of 2017.
Troup, who was speaking at a Montgomery County Council forum on the Red Line, also said that date could change again based on Purple Line construction. Metro wants to sync the shutdowns required by the waterproofing work with work on the planned southern entrance to the Bethesda Metro Station that will go across Elm Street from Bethesda’s Purple Line station.
“A lot of this is dependent on the Purple Line,” Troup told the council’s Transportation, Environment & Infrastructure Committee. “We may advance this work quicker.”
Troup said Metro mitigated about 5,700 Red Line tunnel leaks from 2012 to 2014 and is constantly chasing other water leaks that bring water, sludge and other materials to the tunnel as it passes below downtown Bethesda.
Inside a Red Line tunnel under Bethesda, via Metro.
Reports of smoke and fire from arcing insulators, which can happen when water hits Metro’s electrified third rail, have significantly increased this year.
Metro officials at the forum, which happened last Wednesday, said Metro officials are more aggressively reporting any signs of arcing insulators to local fire departments after January’s fatal incident involving a smoke-filled tunnel near the L’Enfant Plaza station in Washington, D.C.
Council member Roger Berliner, who chairs the council’s Transportation Committee and who represents Bethesda, took a tour of the leaky tunnel in April and said it reminded him of Luray Caverns.
“It’s really, it’s not OK,” Berliner told Troup during the forum. “I know it’s not of your making. But there are waters, there are stalagmites. It’s pretty incredible.”
Troup said the waterproofing work is scheduled for two sets of seven consecutive weekends between June 2017 and November 2017. Crews will use special rail cars that can handle heavy equipment to move 25 precast arches into place and raise them to the tunnel ceiling.
Metro model of how 25 precast arches will be installed in the Red Line tunnel below Bethesda, via Metro.
Construction on the Purple Line, the light-rail network set to run from Bethesda to New Carrollton, could start as early as May 2016. Montgomery County is set to pay the $59.5 million for the Bethesda Metro South Station Entrance, a bank of high-speed elevators on the north side of Elm Street.
The elevators will connect Red Line riders to the Purple Line station, which is set to go under the Apex Building on the south side of Elm Street in the former Georgetown Branch railroad tunnel.
