North L.A. County Braces for More : Weather: Crews race to drain swollen pond that threatens trailer park. A soaked section of Sierra Highway collapses.

Racing to beat the next rainstorm, county crews planned to work through the night Thursday to drain a pond behind an earth dam that threatened to break and pour more water into a flooded Agua Dulce recreational-vehicle park.

Elsewhere in rain-soaked northern Los Angeles County on Thursday, Sierra Highway was closed 10 miles north of Santa Clarita after runoff undermined a 100-foot section of the road, causing it to collapse in an 8-foot-deep hole.

The road will be closed for at least a week, a county spokeswoman said, forcing about 10,000 motorists a day to commute on the busy Antelope Valley Freeway or take a detour onto country roads.

Further west, in Sand Canyon, waters in a rain-swollen wash that was virtually impassable Wednesday had receded sufficiently to allow residents of 47 multimillion-dollar estates to cross.

Most took advantage of the reprieve from stormy weather to stock up on milk and other supplies before the next onslaught.

Forecasters said more rain is expected today, Saturday and Sunday, with showers on Monday and no real clearing until Tuesday.

“The worst thing is, you’re just sort of stuck out here and there’s really nothing to do,” said Skye Ostrom, 18, a college freshman who lives on one of the estates.

Residents of Vasquez Paradise Park in Agua Dulce were coping with more serious problems than boredom.

The trailer park’s 25 residents were evacuated Wednesday when a pond upstream overflowed, flooding the park with up to 4 feet of water.

County engineers determined Thursday that an earth levee at the pond was structurally unsound. The evacuation order will remain in effect until the pond can be drained, said county engineer David Diotalevi.

Sheriff’s deputies allowed residents to return to the park for two hours Thursday afternoon to move their trailers out or collect belongings.

Slogging through slippery mud, many hitched their trailers to pickup trucks and prepared to pull out.

“We don’t know where we’re going, but we’re definitely out of here for the winter,” said Mary Radke, 47, a housewife whose husband, like many residents, is an itinerant construction worker.

Others said they planned to spend a second night at local hotels or with friends or relatives and return to the park when the weather clears.

“This isn’t even a hassle to me, it’s exciting,” said Ian Barrie, 26, whose camper is located on relatively high ground in the park.

Park owner Connie Daiglez promised to refund residents’ monthly rents of about $345 if they chose to leave.

She said the flood also disrupted counseling services she and three other therapists offer at the park.

“We had to cancel all our appointments, but that’s nature for you,” Daigle said. “It’s hard on everyone right now.”

While residents scrambled to vacate the park or grab a change of clothes, crews dug a narrow trench in the levee.

Under the glare of floodlights late Thursday, they were slowly draining the pond, which Diotalevi estimated was about 300 feet wide by 500 feet long and 8 feet deep.

He estimated the job would take at least until early today.

“If this levee went, it’d have a lot of water behind it,” Diotalevi said. “My best advice to residents is to get out and move to higher ground.”

The pond will be permanently drained because it is a hazard, he said. It is located in a former campground owned by Lynn Fortman of Santa Clarita, according to property-tax records.

She could not be reached for comment Thursday.

The pond is on a 23-acre lot, which includes a partially built, 18,000-square-foot mansion and is for sale for $2.6 million.

Times staff writer Julie Tamaki contributed to this story.

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