Caltrans to Close Eastbound I-80 in SF for Full Weekend Repairs

The 71-year-old Bayshore Freeway viaduct will force a reckoning for Bay Area commuters starting next week, when Caltrans shuts down all eastbound lanes of Interstate 80 through a 1.6-mile stretch of San Francisco for a continuous 55-hour window, beginning Friday, April 17 at 11 p.m. and ending Monday, April 20 at 6 a.m.

The closure covers the segment between 17th and 4th streets, one of the most congested corridors in the region approaching the San Francisco-Oakland Bay Bridge. Alongside the mainline closure, Caltrans will also shut both the southbound and northbound Highway 101 Bayshore Freeway connector ramps to eastbound I-80, cutting off two of the primary on-ramps that funnels regional traffic onto the bridge approach.

Vermont Street will serve as the last functional eastbound exit before the closure zone. Drivers who miss it will be pushed onto the 9th Street off-ramp and redirected south on Bryant Street, re-entering the freeway at the 5th Street on-ramp. Caltrans is warning that local streets near 17th, 9th, 10th, 5th, and 4th will absorb significant overflow, with the heaviest spillover expected in SoMa, Mission Bay, and the Design District. Westbound I-80 and the Bay Bridge itself will remain open throughout the weekend.

The shutdown is not an emergency response but a planned milestone in the two-year "Fab-4 Rehabilitation" project Caltrans launched in January 2026, targeting the Central US-101 and Bayshore I-80 viaducts simultaneously. Crews will use the uninterrupted access to apply polyester concrete overlays to the bridge deck, repair deck joints, and rehabilitate barrier rails. The structures have been carrying heavy urban traffic since 1955 without a major overhaul, and Caltrans says the conditions created by decades of seismic stress and weather exposure have made the timeline urgent. "With constant exposure to heavy traffic loads, weather, and seismic demands, the structures require timely rehabilitation to prevent further deterioration," the agency said in its project documentation.

Caltrans cited the concentrated weekend closure model as the most practical approach for work of this complexity. "Performing this work now allows Caltrans to address critical maintenance needs, preserve the existing infrastructure, and ensure continued safety for motorists, commuters, pedestrians, and cyclists traveling through and beneath the structure," the agency said.

Detour maps and video guides are available at sfhighwayprojects.com. Caltrans is explicitly urging drivers to use Muni and other public transit for the full weekend rather than attempting to navigate around the closure on surface streets. "Significant congestion and travel delays are expected across SoMa, Mission Bay, and surrounding corridors," the agency warned. "Consider using public transportation."

The April 17 closure is not the last disruption tied to this project. The two-year rehabilitation timeline means additional lane reductions and potential full closures are likely through 2027 as crews work through the remaining deck and structural repairs on both viaducts.