Rain falls on parched California; flood watches extended for some areas

A storm that saturated California for a second day Wednesday was just what the dry state needed, adding water to depleted reservoirs, quenching crops and even awakening picturesque waterfalls.

There was some flooding and evacuations in areas where hillsides were left barren by wildfires, but major damage was avoided despite some huge rainfall totals. One location, Yucaipa Ridge in the San Bernardino Mountains, received just under 25 centimetres of rain, the National Weather Service said.

Most other parts of the state received totals between five and 10 centimetres.

The storm dropped snow in mountains key to the state's water supply, and it made signature waterfalls flow at Yosemite National Park, including the 740-metre Yosemite Falls that had slowed to a trickle by mid-July.

"With the precipitation, they are looking good. They are flowing nicely," park spokeswoman Ashley Mayer said.

There were problems. The storm was the likely cause of a pair of sinkholes in San Francisco, including a six-by-nine metre chasm in a residential neighbourhood on the city's west side.

And Sacramento's rush-hour commute was disrupted by freeway flooding. The California Highway Patrol reported that roadway flooding blocked two of three lanes along Highway 51, known as Capital City Freeway, and affected lanes farther north along Interstate 80.

On Tuesday, gushing water and muddy debris poured from hillsides about 80 kilometres northwest of Los Angeles, forcing the evacuation of about 75 homes in Camarillo Springs for much of the day.

When the order was lifted, authorities urged people to stay away voluntarily. No major damage was reported.

In Orange County, about 60 homes in rural Silverado Canyon remained under a voluntary evacuation notice. The area burned over the summer and has been the site of previous mudslides.

In the San Francisco Bay Area, the rain expected to last through Thursday brought the region close to or beyond normal annual rainfall totals for the first time in years.

Just before the storm arrived, the Sierra Nevada snowpack which counts for most of the state's water supply was at just 24 per cent of normal for this time of year. But snow was building rapidly with reports of 25 centimetres of snowfall at elevations of 2,440 metres.

That good news was tempered by a stark reality: California needs many more such storms to pull itself out of a three-year drought.