Around 2:30 a.m. Wednesday morning, a ruptured water main at 15th Avenue and Wawona Street in West Portal sent a "waist high wall of water" rushing down the street, flooding homes and leaving behind a deep sinkhole on 15th Avenue.

Utility crews took about an hour to shut off the water, but that was enough time for the river of water to trap some residents outside of their flooded homes and leave high-water marks on parked cars. One neighbor told KTVU his home had about a foot and a half of water in it. Another neighbor's home received extensive damage to a bedroom where her 14-year-old son had been sleeping.

Crews were on the scene this morning cleaning up the muddy mess with bulldozers and hosing down cars and driveways in the torrent's path.

As of around 7 a.m. this morning, fire crews said neighbors still have access to domestic water, but the city's Department of Building Inspection was still checking on the safety of the buildings affected.

The Mercury News has more photos of the sinkhole and KRON4 news brings us the video report:

Just last week another water main broke across town in Russian Hill.

Update 3:30 p.m.: The water, power and sewer branch of the city's Public Utilities Commission sends in an update:

San Francisco, CA - At approximately 3:00 a.m. on Wednesday, February 27th, crews responded to water flowing from underneath the intersection of Wawona Street and 15th Avenue in San Francisco. The 16-inch cast iron pipe under the road dates back to 1952, and pulled apart at a joint near that intersection. The cause is still under investigation. This water transmission line transports water from Sutro Reservoir to the Excelsior District. Only one resident lost water service.

At this time, 23 homes and 12 vehicles suffered water damage. Water service was restored to the single residence without water at 3:00 p.m. Six residences were yellow tagged by the Department of Building Inspection, and will be reassessed by City staff to assure they are structurally safe. However, no residents have been displaced because of this incident. Residents who wish to file a claim with the City should contact the City Claims Department at 415-554-3900.

Crews cleaned up the mud and debris from the site throughout the day. Repairs to the water line will be completed this evening.