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Summer session classes, conferences and day camps are called off, and Madera Grove, CCSC and Stock Farm Road childcare facilities on the main campus are also closed, university officials announced in a tweet Tuesday.
According to the university, one of the main PG&E transmission lines that feeds into the campus is reportedly down. Officials said efforts are under way to transfer power to an alternate line, but were unable to give a time frame.
T.J. Rodgers, co-owner and winemaker at Woodside's Clos de la Tech in one of the evacuation zones, told KCBS Radio he heard a "big" explosion at around 2:45 p.m. which prompted a power outage.
"It was like a cannon going off, there were two of them," Rodgers recalled. "Then the mushroom cloud went up."
Nearly 13,500 San Mateo County residents and more than 20,700 Santa Clara County residents were without power as of 6:57 p.m., although the unplanned outages' causes weren't clear.
Stanford employees who work on the main campus were encouraged to work from home Wednesday. The university also supplied flashlights and made respite areas for students to gather.