SAN FRANCISCO (CBS SF) – Nearly two dozen homes and a number of cars were damaged by flooding after a water main ruptured in San Francisco’s Inner Parkside neighborhood early Wednesday morning, a city Public Utilities Commission spokesman said.

The 16-inch cast-iron main broke shortly after 2:30 a.m. on 15th Avenue just south of Wawona Street, sending a river of water and mud down the hill.

An estimated 23 homes and 12 vehicles were damaged, SFPUC spokesman Tyrone Jue said. He said the pipe that ruptured was installed in 1952.

Resident Kevin Flores, 24, was woken up by his brother as the water came gushing into their 15th Avenue home.

“The water was already up to my knees,” Flores said. “I thought the ocean had come in.”

Another neighbor, 71-year-old Marian Simonian who has lived in her home for 50 years, said there have been previous water main breaks in the neighborhood but “nothing like this.”

The water went through her home and into the backyard, she said.

Six homes have been yellow-tagged by the city, meaning they were damaged and have limited areas that are habitable, Jue said.

A large sinkhole opened up on 15th Avenue at the site of the break, and will take several hours to repair, he said.

All customers still have water service except for one home directly west of the sinkhole, he said.

Anyone who suffered property damage is asked to call the city attorney’s claims division at (415) 554-3900.

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