100-year old Twin Peaks Tunnel Reconditioned

The overhaul of the Twin Peaks Tunnel which took 2 months since May has finally completed and San Franciscans can once again have light rail service on the M, L, and K lines beyond Castro Station.

The 100-year old subterranean tunnel was in dire need of an overhaul and refurbish and renovation was long overdue.


Repairs and maintenance took about 2 months to the dismay and inconvenience of many San Franciscans who rode the Muni train between Castro Station and West Portal. The closure also caused Muni driver shortage.


SFMTA had said:

During the closure, Forest Hill and West Portal stations will be closed, the K Ingleside will travel on a shortened route, and bus service will run for the L Taraval and M Ocean View lines.

[…] During weekday morning rush hour (6 a.m.-10 a.m.), Muni customers transferring from M buses or K trains to BART at Balboa Park can receive a free BART single-ride ticket, good for travel downtown through Embarcadero BART Station.

Only S Shuttles and T Third trains will operate underground through Castro and Church stations.


San Francisco credits the 2.25 mile Twin Peaks tunnel with transporting some 80,000 riders a day. The tunnel now includes “a full track replacement, replacement of the tunnel drainage system, new fire suppression system at West Portal station, and seismic upgrades.”

Source: Curbed SF, Google

Leave a Reply

Your email address will not be published.