Walnut Creek commuters will face Caldecott Tunnel bore closures on five nights starting Monday, Oct. 5, as Caltrans performs overnight work on State Route 24.
Each closure runs from 10 p.m. to 4:30 a.m. At least one bore in each direction will stay open every night, Caltrans District 4 said on X.
Here is the full schedule:
- Monday, Oct. 5: Bore 2, eastbound
- Tuesday, Oct. 6: Bore 1, eastbound
- Wednesday, Oct. 7: Bore 3, westbound
- Monday, Oct. 12: Bore 2, eastbound
- Tuesday, Oct. 13: Bore 1, eastbound
Four of the five closures affect eastbound traffic, the direction Walnut Creek-bound drivers travel through the tunnel from Oakland and Berkeley. The lone westbound closure is Wednesday, Oct. 7.
Caltrans did not publish specific detour routes. Drivers who hit a closed bore can use whichever bore remains open in their direction. Expect delays.
The overnight work comes as Caltrans prepares for a much larger project at the tunnel. A $267 million rehabilitation is tentatively set to begin in November 2026 and last through approximately fall 2029, according to the Caltrans project page. That overhaul will address cracked concrete, rust and water damage, electrical and lighting systems, and install new ventilation fans and a fire-suppression sprinkler system.
The tunnel carries more than 160,000 commuters daily through the Oakland and Berkeley hills, connecting Contra Costa and Alameda counties, according to Caltrans.
Caltrans says the closures are for flat-jack testing, full-depth roadway saw-cutting and routine maintenance. The work is weather-dependent, and the schedule may change.
Residents can sign up for Caldecott Tunnel closure alerts through the Caltrans mailing list. Real-time lane and ramp closure information is available on Caltrans QuickMap.
