San Francisco riders heading toward the South Bay next weekend should build a substantial delay into their trip.
BART will suspend train service between Union City and Warm Springs/South Fremont on Saturday and Sunday, Aug. 29–30, while crews work on a major track-rebuilding project near Fremont Station. The shutdown also means the Green Line will not operate between Daly City and Berryessa/North San Jose during the work days.
BART says riders should expect 30 to 40 minutes of additional travel time through the affected area.
Free buses will bridge the closed section
AC Transit buses will replace trains between Union City, Fremont and Warm Springs/South Fremont. BART says the bus bridge will include direct service between Union City and Warm Springs as well as a "hopper" service that also stops at Fremont.
Fremont Station will have no train service during the shutdown, but it will remain open for the replacement buses.
For someone beginning in San Francisco, the practical effect is a broken rail journey: train, bus and then train again for destinations farther south. The transfer itself is part of the reason BART is warning of a 30–40 minute delay.
Why BART is closing the tracks
The work centers on an interlocking near Fremont Station, a section of track infrastructure that allows trains to move safely from one track to another. BART says the equipment has been in service for decades and must be replaced.
The Aug. 29–30 shutdown is part of a sequence of weekend closures connected to that project. Additional work weekends are scheduled for Sept. 12–13 and Sept. 26–27.
The construction has already changed Fremont Station outside the shutdown weekends. BART previously announced that about 750 of the station's roughly 1,900 parking spaces would be temporarily closed through early 2027 to stage equipment for the rebuilding project.
The Orange and Blue lines also change
The impact is not limited to the Green Line label on the map. BART says an Orange Line train will operate a loop between Warm Springs/South Fremont and Berryessa/North San Jose, with northbound departure times adjusted ten minutes earlier.
The final two evening trips from Berryessa that are normally scheduled for 11:38 p.m. and 11:49 p.m. will be canceled on the work days; BART directs riders to the 11:10 p.m. departure instead.
Blue Line departures from Dublin/Pleasanton and Daly City will also differ from the regular weekend schedule.
Check the trip before leaving
BART has incorporated the temporary schedule into its trip planner. Riders making time-sensitive airport, event or South Bay connections should check the itinerary again on the day of travel rather than rely on a normal weekend timetable.
SF News Today's live transit page also tracks BART and Muni service alerts and arrivals. Planned construction, however, is best treated differently from a surprise delay: next weekend's interruption is known in advance and can add more than half an hour to some journeys.