BART Service Disrupted Between SFO and South San Francisco After Track Equipment Failure

A track equipment failure near San Bruno severed train service between San Francisco International Airport and South San Francisco on Thursday morning, leaving airport-bound riders scrambling for alternate routes during the height of the morning commute.

BART issued a service advisory at 8:43 a.m. confirming a major delay across the SFO Line in the Antioch, Richmond, SFO, and Millbrae directions. The gap hit the stretch most critical to travelers: the direct rail connection into SFO, where any lost train can translate into a missed flight. With no trains running between SFO and South San Francisco, riders faced a patchwork of imperfect alternatives.

The agency ran shuttle trains on two circuits — one between SFO and Colma, another between SFO and Millbrae — while Red Line service was cut to limited runs between Richmond and Daly City and Yellow Line service was reduced between Antioch and Colma. SamTrans stepped in with bus coverage: Routes 142 and the southbound EPX ran between San Bruno and SFO, while the ECR route connected Millbrae and Daly City. Bus substitutes, however, cannot match BART's frequency or bypass Peninsula traffic, adding time and uncertainty for anyone with a boarding time.

Service was eventually restored, but the failure landed on a corridor already under active construction. BART has been installing a Communications-Based Train Control system between Millbrae and SFO since January 2025, a modernization project that has brought planned 30-minute nightly delays on the stretch and is not expected to finish until Summer 2026. Thursday's equipment failure was unplanned and separate from that scheduled work.

The broader reliability picture for the San Bruno segment is troubling. A February 2026 analysis drawing on two years of BART delay data obtained through a public records request found the agency logged 35,105 delays of 10 minutes or more between November 2023 and November 2025 — the equivalent of at least 5,850 hours, or 243 days, of cumulative passenger delay. Equipment failures ranked among the leading causes systemwide.

BART is simultaneously managing a $376 million budget deficit and has warned it may be forced to cut or reduce services if one-time state and federal funding runs out. Transit advocates are pushing for a regional sales tax measure on the November 2026 ballot to stabilize funding before that cliff arrives.

For commuters whose only rail path to SFO runs through San Bruno, Thursday's failure illustrated the vulnerability of that single-point connection. The CBTC upgrade, once complete, is designed to allow trains to run closer together and increase core Transbay capacity from 24 to 30 trains per hour per direction. Whether it also reduces unplanned Peninsula failures is the more urgent question riders will be asking.