SAN FRANCISCO — A full weekend shutdown of westbound Interstate 80 will force Bay Bridge traffic and other drivers off the freeway before the Bayshore viaduct beginning Friday night.
Caltrans says all westbound I-80 lanes between 5th Street and 15th Street will close at 11 p.m. Friday, Oct. 23, and are scheduled to reopen by 6 a.m. Monday, Oct. 26. The work is part of rehabilitation of the Central and Bayshore freeway viaducts.
Where does westbound I-80 close?
The closure begins after the downtown exits and extends through the westbound I-80 segment toward the U.S. 101/I-280 connections. Caltrans says traffic will be diverted at Fremont Street and Fifth Street, with Fifth Street serving as the final exit before the closure limits.
The San Francisco–Oakland Bay Bridge itself is not the work zone. The practical problem is for drivers who cross the Bay Bridge into San Francisco and then expect to remain on I-80 toward U.S. 101, I-280, the Peninsula or SFO.
What detours should drivers use?
Caltrans has published detour resources directing motorists from the Fremont and Fifth Street exits to surface streets, with options to reconnect to westbound I-80 or reach I-280. Because downtown and SoMa streets can back up quickly when freeway traffic is diverted, the agency is urging motorists to plan ahead.
If the trip can be shifted away from the closure window, that is the simplest option. Otherwise, check Caltrans QuickMap or 511 immediately before departure and allow extra time for surface-street congestion.
Why is I-80 closing for the full weekend?
Crews are scheduled to place polyester concrete on the westbound freeway deck, completing a broader viaduct concrete-placement project that began on eastbound I-80 earlier this year.
Caltrans says the Central and Bayshore viaducts are 71 years old and need rehabilitation because of heavy traffic, weather exposure and seismic demands. The agency says the work is intended to extend the structures’ service life, improve ride quality and enhance safety.
What should Bay Bridge drivers know?
- Coming into San Francisco: be ready to exit at Fremont or Fifth before the closure.
- Continuing toward U.S. 101, I-280 or SFO: expect a surface-street detour and additional travel time.
- Closure timing: 11 p.m. Friday through 6 a.m. Monday.
- Schedule: Caltrans says work is weather-dependent and can change.