According to PG&E, the outage began around 9:45 a.m. and affected approximately 9,400 customers. The interruption disrupted businesses, shuttered traffic signals and renewed concerns about the reliability of the area's aging electrical infrastructure.
At Joe's Pharmacy on Geary Boulevard, pharmacist Tony Bastian said the outage impacted his ability to provide critical health care services to customers.
"We need to come up with new infrastructure. This is not acceptable," Bastian said.
MORE: Frustrations running high in San Francisco's Sunset District over multiple power outages
Without electricity, Bastian said he was unable to fully serve patients who depend on the pharmacy.
"If I don't have electricity, I cannot deliver that community service. I cannot deliver the health care I'm supposed to, and that is not right," he said.
Nearby businesses scrambled to stay open despite the outage. At Cigarettes Cheaper, employee Aziz Amari continued serving customers using cash transactions and candlelight.
"Still open for my customers -- only cash," Amari said.
He also worried about merchandise losses as freezers sat without power.
"Ice cream, when it melts, no one's going to buy it," he said.
Residents reported seeing possible electrical problems before the outage. Allyssa Walter said she witnessed a power line sparking near Anza Street and 16th Avenue.
"It started smoking and sparking. Sparks were flying on the floor, then it exploded out of nowhere with a big power flash," Walter said.
The outage also created traffic congestion as signal lights went dark along major streets, including Park Presidio Boulevard.
In a statement, PG&E said, "During a routine operational procedure between two San Francisco substations, a protective device on the system activated and there was an outage. Initially, about 9,400 customers in the Richmond and Golden Gate Park neighborhoods were affected."
Earlier Saturday, PG&E's outage reporting system incorrectly showed more than 120,000 customers without power. The utility later attributed the discrepancy to a system glitch.
The outage is the latest in a series of power disruptions affecting the neighborhood. Residents point out that it is at least the fourth significant outage in the area in the past seven months. In December, a fire at a PG&E substation triggered a widespread blackout across parts of San Francisco.
At Royal Market and Bakery, owner Vardges Kazaryan toured his darkened store by flashlight, concerned he could once again lose refrigerated inventory.
"No power, no people, no money," Kazaryan said.
PG&E said service was fully restored Saturday afternoon. The utility is investigating the cause of Saturday's outage and if the arcing power line at 16th Avenue and Anza Street played a role.
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