Checked September 8, 2026, at 5 p.m. Pacific. Caltrans currently schedules another full northbound U.S. 101 closure through San Francisco’s Hospital Curve from 11 p.m. Friday, September 18, to 6 a.m. Monday, September 21. All times below are Pacific. This is a scheduled construction closure, not a live report that the road is closed today.
If you are coming from SFO, the Peninsula, or the South Bay, the practical takeaway is to plan around northbound 101 before you reach the work zone. Caltrans recommends I-280 as an alternative and encourages public transportation.
The closure at a glance
| Item | Current published plan |
|---|---|
| Starts | Friday, September 18, 2026, at 11 p.m. |
| Scheduled reopening | Monday, September 21, 2026, at 6 a.m. |
| Direction affected | All northbound lanes through the Hospital Curve closure area |
| Southbound lanes | Caltrans says they will remain open during this northbound closure |
| Main alternate route | I-280 northbound; select the onward route for your destination |
| Schedule qualification | Work is weather dependent; check current notices before departure |
The September 7 Caltrans update describes the upcoming closure as Cesar Chavez Street to 17th Street and reconfirms the September 18–21 hours. It also reports that the Labor Day closure ended at 1:16 a.m. on September 7.
The older notice, published September 3, mixed 10th Street and 17th Street endpoints; KQED’s September 2 reporting also used 10th Street. For current planning, use the newer Caltrans notice, official detour maps, and posted traffic controls—not the older endpoint wording as a promise of ramp access.
Which route should you plan around?
| Your trip | Planning guidance |
|---|---|
| North from SFO, the Peninsula, or South Bay | Review the official I-280 alternative early. KQED’s account of the Caltrans SFO map routes travelers via westbound I-380 to northbound I-280. |
| Toward downtown San Francisco or the Bay Bridge | Caltrans recommends northbound I-280 as the alternate corridor. Check the onward connection for your destination; I-280 itself does not cross the Bay Bridge. |
| Local destination near the closure | Check local access and current detours, not just the through-route. Nearby streets can also experience delays. |
| Southbound on U.S. 101 | The published plan keeps southbound lanes open, but this does not guarantee uncongested travel or rule out unrelated incidents. |
I would treat this as a corridor-level planning decision, not a last-minute search for a side-street shortcut. KQED reports Caltrans expects substantial effects on surrounding streets and I-280 entrances as well as the closed highway. Neither source provides a dependable delay estimate for your individual trip.
Before you leave
- Check Caltrans’ San Francisco highway-project updates for schedule changes and official detour maps.
- Check Caltrans QuickMap for current closures, incidents, and traffic conditions.
- Look at 511 Bay Area and the relevant transit agency’s trip planner if transit is an option.
- Plan the route to your actual destination, including the last part of the trip after leaving I-280.
- Leave extra flexibility for time-sensitive travel, and recheck conditions before returning.
For riders, the closure applies just as it does to other northbound traffic. Lane splitting is not a route through a closed freeway or work zone. Follow the posted detour and traffic controls.
Why a whole weekend?
Caltrans describes major pavement rehabilitation with crews working around the clock during each closure weekend. KQED’s interview with the agency explains that the scope of repaving and suitable dry conditions are factors in the schedule.
The first September closure was scheduled for September 4–7. This guide focuses on the next announced window, September 18–21; it should not be read as a current account of the earlier weekend or as a guarantee of reopening at a particular minute.
FAQ
Is Highway 101 closed in both directions?
Not under this September 18–21 plan. Caltrans says all northbound lanes in the closure area will close while southbound lanes remain open.
Does the closure shut down the Bay Bridge?
This notice is for northbound U.S. 101 at Hospital Curve, not a Bay Bridge closure. It can still affect trips heading toward the bridge.
Can the dates or reopening time change?
Yes. Caltrans says the work is weather dependent. Check the latest agency notice and live conditions rather than relying solely on this dated guide.
Bottom line: Put September 18–21 on your travel calendar, plan the I-280 alternative where appropriate, and verify the official route before leaving.