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Twin Peaks Tunnel Construction Held Until Summer

Thank you for your continued interest in the Twin Peaks Tunnel Improvements Project.

The April construction start has been postponed until the summer due to additional technical analysis required for the tunnel. In an effort to keep construction to its shortest duration, the start of construction is being held until the contractors and project staff have addressed these issues and can start working safely and efficiently on the tunnel improvements. The construction schedule is currently being revised to reflect the summer start, and dates of the first shutdown will be released once confirmed.

Century old Twin Peaks Tunnel needs major improvements and seismic upgrades to ensure it can continue to safely transport 80,000 daily riders through the 2.25 mile tunnel for years to come. Extensive improvements are planned for the tunnel, which runs between Castro and West Portal Muni stations. This work includes a full track replacement, replacement of the tunnel drainage system, new fire suppression system at West Portal station, and seismic upgrades at the eastern end of the tunnel. Construction is anticipated to be completed over five tunnel closures, with each closure lasting up to two weeks. The start of construction is anticipated to begin this summer and finish in summer 2018.