Twin Peaks Tunnel closed for construction starting Monday, June 25 for approximately two months

During construction, most of the active work and staging outside of the tunnel is planned to occur on West Portal Avenue between Ulloa and Vicente. All of the businesses will remain open as will the sidewalks in front of them. We are working closely with local businesses to accommodate loading access throughout the project.

In order to create a work zone for crews to take materials in and out of the tunnel during the approximate two month project, the southeast portion of West Portal Avenue will be blocked off to traffic and parking. 

During the daytime from 7:00 a.m. to 9:30 p.m., the northwest side of West Portal Avenue will maintain one-way traffic and will have parallel parking. Overnight from 9:30 p.m. to 7:00 a.m. the entire block on both sides will be closed to parking and traffic, but the sidewalks will remain open. See below diagrams for more information.

Daytime Traffic Pattern and Construction Zone:

Nighttime Traffic Pattern and Construction Zone:

Printable version of diagrams [pdf]

Nearby residents and merchants should be prepared for work to occur 24-hours a day, 7 days a week. Crews will be working hard to keep noise down in the evening, but in order to finish the project quickly, they need to work at night.

We will continue to send out weekly updates about construction and the progress on the project. Thanks in advance for your patience as we work to complete this vital safety project in the Twin Peaks Tunnel.

This Weekend

There will not be overnight closures to the tunnel this weekend and transit will be running additional service in support of the SF Pride activities.

Additional Project Background

With 100 years of service under its belt, Twin Peaks Tunnel needs extensive work to its interior to continue to operate safety and reliably for years to come. This vital part of our transit rail system connects Castro Station to West Portal Station and serves over 80,000 K Ingleside, L Taraval and M Ocean View customers every day.

The tunnel's infrastructure, including the tracks, walls and drainage systems, must be maintained in a timely manner to keep up with the demands of the Muni system. Twin Peaks Tunnel is currently under a speed restriction, which slows down trains as they travel through. Replacing the tracks will lift the tunnel's speed restriction and keep trains running reliably through the system. Seismic reinforcements will better protect the tunnel's overall structure and stability. 

To help Muni customers get around during the closure, a video with map animations highlighting temporary stops, transfer points and alternative routes can be found online. In addition, a comprehensive rider guide in English, Chinese, Spanish and Filipino is available to view or print on our website.

More information and details can be found at SFMTA.com/TwinPeaks