Police received the call about the flooding at 4:20 a.m. The flooding was caused by a shear break of an 82-year-old water pipe that feeds and discharges to a reservoir that services the southeast portion of the city. The water department has called it a catastrophic failure. Crews estimate that 45,000 gallons of water were released from the reservoir, which holds nearly 1 million gallons.
"It's an eight-inch cast iron pipe and it sheared off up on the hillside," Daly City Water Resources spokesperson Patrick Sweetland said. "We measure at about 45,000 gallons of water. Crews isolated the valve in about 10 minutes upon their response from the PD dispatcher."
Dozens cars became stuck on the street with mud caked up to the tops of their wheel wells.
About 12 homes near the tank were temporarily evacuated over concerns that the hillside could collapse. After city engineers inspected the hill, residents were allowed back inside their homes.
"Fortunately, the debris did not impact homes directly just the streets and cars that were parked in the area," North County Fire Authority spokesperson Matt Lucett said.
Daly City Water said no customers actually lost water, but some had very low water pressure. The department thinks the hillside will hold for now, but rain is expected later this week.
The same reservoir caused a flood about 14 years ago. The massive tank was being filled, when the shut-off valve malfunctioned, sending water down the hill, into the backyards of four homes.
Amy Hollyfield, Terry McSweeney, Healther Ishimari, Lyanne Melendez and Vic Lee contributed to this report.