Project replaced tracks and repaired key equipment inside the tunnel, including a new overhead contact system, fire sprinkler valve refurbishment, seismic upgrades, and rebuilt platforms at 28th Avenue. The work, which started in November 2014, was originally planned to finish by June 2015, but was not completed until October 2017. During some weekends, the tunnel was closed and N Judah was short-turned at Church & Duboce. Buses were used to continue service to Ocean Beach. A combination of additional needed work that was discovered during construction, plus nearby residents challenging a night work permit, resulted in delays to the project and an additional $4 million cost for a total of $23.3 million. References External links . Video showing N Judah train towing Toyota Prius out of Sunset Tunnel. Muni Metro Railroad tunnels in California Tunnels in San Francisco Tunnels completed in 1928 Sunset District, San Francisco Western Addition, San Francisco