San Rafael residents heading home from San Francisco over Labor Day weekend will hit a dead end on US-101. Caltrans is closing all northbound lanes at the Hospital Curve starting Friday, Sept. 4, at 11 p.m.

The closure runs through Monday, Sept. 7, at 6 a.m., shutting down the stretch between Cesar Chavez Street and 17th Street, according to a Caltrans press release. Crews will repave lanes around the clock during the shutdown.

Southbound lanes will stay open.

Caltrans District 4 said on X that motorists should use northbound I-280 as the primary detour. Drivers coming from SFO or the Peninsula can take I-380 to I-280 to reconnect to US-101. The agency also recommended public transit as the best option to bypass congestion.

About 44,900 people travel daily on the San Francisco freeways covered by the broader rehabilitation effort, according to Caltrans.

The closure is part of the Hospital Curve Rehabilitation Project, a two-year effort that began in fall 2025. The project covers 15.4 lane miles of concrete pavement, drainage systems and median barriers on US-101 between Candlestick Point and the Mission District. Caltrans expects to finish the work by 2028.

All work is weather dependent, according to Caltrans.

A second full northbound closure is scheduled for the weekend of Friday, Sept. 18, through Monday, Sept. 21, with the same 11 p.m. to 6 a.m. schedule. The overall project calls for four total full weekend closures, two in each direction.

Caltrans Public Information Officer Lori Shepherd is the agency contact for the project. Detour maps and videos are available at sfhighwayprojects.com, and drivers can call 1-800-427-ROAD for highway conditions.