Cars with human drivers were forced to try to navigate between the vehicles after the widespread power outage in the Bay Area left them without traffic lights.

Waymo is resuming its driverless taxi service after a large blackout across San Francisco left its cars stranded in the streets on Saturday night.

Videos shared on social media showed the self-driving cars blocking roads and intersections as a widespread power outage left a large portion of the city in the dark. In a video shared on X, one of the Waymo vehicles appeared stuck at an intersection, with four other Waymo cars and flashing hazard lights blocking the road behind it.

bad day to be a Waymo in SF during a PG&E-induced power outage pic.twitter.com/3SwEP993zn

— Mishaal Abbasi (@WhereIsMishaal) December 21, 2025

Cars with human drivers were forced to navigate between vehicles in a narrow section of the street.

The issue spurred a temporary suspension of Waymo`s service on Saturday, but the company returned to offering rides once power was up the next day, CNBC reported.

A Waymo spokesperson said the blackout caused disruptions, including "non-functioning traffic signals," in a statement to CNBC on Sunday.

"While the Waymo Driver is designed to treat non-functional signals as four-way stops, the sheer scale of the outage led to instances where vehicles remained stationary longer than usual to confirm the state of the affected intersections," the spokesperson said. "This contributed to traffic friction during the height of the congestion."

A representative for Waymo did not immediately respond to a request for comment.

It`s unclear what caused the outage, but it appears some of it may have been due to a fire at a Pacific Gas and Electric Co. substation, according to the utility. The outage that began on Saturday afternoon affected approximately 130,000 homes and businesses at its peak.

San Francisco`s Department of Emergency Management said that there were "significant transit disruptions" citywide on Saturday and encouraged residents to avoid travel if they could. Some of the city`s Bay Area Rapid Transit and Muni bus stations were bypassed because of the outages, according to reporting from The Associated Press.

Waymo, which is owned by Google parent company Alphabet, initially launched its service in the Bay Area and plans to expand to major metropolitan areas across the country, including Washington, D.C., Atlanta and Miami.

It opened up its service in Los Angeles County last year, one of its biggest markets to date. The company also received a permit in August to conduct test rides in New York City with a limited number of cars.

Major companies are competing in the autonomous ride business, with technology titans such as Tesla and Amazon testing out their own services to rival Waymo.

Cruise, a startup owned by General Motors, had its permits revoked in 2023 due to safety concerns. One of its cars dragged a pedestrian for 20 feet while she was pinned underneath the vehicle in October that year.

The incident sparked a recall of nearly 1,000 of Cruise`s vehicles and a federal probe into the safety of the company`s robotaxi program. Cruise did not relaunch and GM announced in December 2024 that it would no longer pursue driverless "robotaxi" services.

Waymo Halts SF Robotaxis