Large parts of San Francisco were plunged into darkness on Saturday following a major power outage that disrupted daily life across the city and brought traffic to a near standstill. Nearly one-third of the city, home to over 800,000 residents, was affected as electricity cuts stretched from morning well into the day.
Several neighbourhoods remained without power for hours, forcing residents to navigate unlit streets. Some were even seen celebrating birthdays outdoors amid the blackout, highlighting the scale and duration of the disruption. Public transport services were hit, businesses were forced to shut down during a peak holiday shopping period, and normally busy commercial zones fell unusually quiet.
The outage severely impacted road traffic. With traffic signals offline, congestion worsened across multiple intersections. Autonomous robotaxis were seen stalled or blocking roads, compounding gridlock and nearly causing accidents, according to videos circulating on social media. Drivers reported long delays while attempting to cross the city, with some lanes obstructed by immobilised self-driving vehicles.
Waymo, the company operating autonomous robotaxis in the city, said its priority was rider safety and ensuring emergency personnel could move freely while the situation was being addressed.
City authorities urged residents to stay off the roads unless absolutely necessary, warning that several traffic signals remained non-functional. Police officers and traffic personnel were deployed to manually manage key intersections as weather conditions worsened with fog and incoming rain.
The city&rsquo;s mayor confirmed that the blackout was caused by a fire at a substation and said it was unclear when full power restoration would be completed. An emergency operations centre was activated to monitor the situation and coordinate response efforts.
Officials said approximately 130,000 customers were affected at the peak of the outage. A city-wide outage map showed the western parts of San Francisco were hit the hardest, including areas such as Richmond, Sunset, Presidio, and Golden Gate Park.
By late evening, a majority of customers had their electricity restored, though authorities continued to monitor remaining affected zones as recovery efforts progressed.

John Mleczko, left, and Julia Cooke, both of San Mateo, sit on a bench with their friend

Power outage halts traffic, stalls self-driving cars, disrupts daily life

San Francisco plunged into blackout chaos

Power outage halts traffic, stalls self-driving cars, disrupts daily life

December 21, 2025 | 16:00 IST