Underground electrical vault fire disrupts San Francisco Financial District

What happened

At least four underground electrical vaults in San Francisco's Financial District caught fire or erupted on the morning of 1 October 2026, after smoke was reported from vaults near California Street and Front Street. The San Francisco Fire Department responded with about 70 personnel, and PG&E crews were on site. A shelter-in-place order covered parts of those streets, with road closures and heavy traffic during the morning commute. Police said the order was lifted just after 11 a.m. and that emergency crews had left, with residual delays expected.

No injuries were reported. PG&E later said the cause was an issue related to an underground cable. An earlier PG&E statement had said the cause was not yet known and that there were no customer outages associated with the incident at that time.

Contributing factors

PG&E later attributed the fire to an issue related to an underground cable. A fire department spokesperson said that, in the past, vault fires have been sparked by equipment malfunction or trash near equipment, but the source does not confirm either of those for this incident.

Lessons learned

1. Coordinate isolation of live underground equipment between the fire service and the network operator before and during firefighting.
2. Plan traffic management for vault fires in dense city centres, where street closures can gridlock the morning commute.
3. Update the public promptly when a shelter-in-place order is lifted, and say what is still unknown about outages and cause.

Source

sfgate.com