Twin Peaks tunnel closure to slow Muni this summer

Muni riders should brace themselves for another subway shutdown scheduled for this summer.

It’s actually more of a partial shutdown of the Twin Peaks Tunnel so that the San Francisco Municipal Transportation Agency can start replacing rail tracks. Documents from the SFMTA said tracks in the tunnel were last replaced in the 1970s.

Riders may recall that the transit agency recently completely shut down the subway each night for six months to replace emergency phones and an old radio system. The transit agency completed most of work in January before Super Bowl 50 events.

This time, the transit agency will close the subway on 21 weekends at West Portal and Forest Hill stations starting on Friday nights and reopening subway service for Monday morning. The agency’s website said it plans to start work sometime in the summer.

Train service would remain running between Castro and Embarcadero stations. Julie Kirschbaum, operations planning and scheduling manager for the SFMTA, said details are still being finalized on a bus bridge for Muni riders on outer portions of the K-Ingleside, L-Taraval and M-Ocean View lines.

The SFMTA’s Board of Directors on Tuesday awarded the Twin Peaks Tunnel Trackway Improvement Project contract to NTK Construction Inc., for $33 million. The work will include replacing the entire rail track structure (ties and ballasts) between West Portal and the abandoned Eureka Valley stations.

Seismic upgrades to the Eureka Valley Station and inspecting and cleaning of tunnel’s drainage line and manholes will also be performed during the closure, the transit agency said.

SFMTA Director of Transportation Ed Reiskin said the plan is to avoid doing any work for weekend special events, which why the work is getting done non-consecutively.

Both Reiskin and SFMTA Board Director Cheryl Brinkman said they understand the inconveniences for riders, but said the work was critical to improve the reliability of the subway.

The total cost of the project is $52 million and funded through federal grant funds, revenue bonds and bridge toll funds.

SFBay will keep you posted on when the work will begin, and plans for the bus bridge.