Powerful Storm Triggers Floods : Weather: Helicopter rescue crews pluck stranded, terrified drivers from car roofs and treetops. The deluge strikes the San Fernando Valley the hardest.

A powerful Pacific storm pounded Southern California on Monday, triggering mudslides and floods that stranded motorists and forced helicopter rescue crews to pluck terrified drivers from car roofs, treetops and telephone poles.

The worst of the storm hit the San Fernando Valley, where near-record amounts of rain fell causing the worst flooding in Los Angeles in the last half a century, according to weather officials.

The deluge caused the swollen Los Angeles River to overflow its banks in the Sepulveda Dam Basin in Van Nuys, sending a torrent of water onto Burbank Boulevard and nearly submerging dozens of vehicles.

Rescue crews from the Los Angeles Fire Department rescued 48 people from the dam flood, including at least four people who required hospitalization for minor injuries.

As a result of the flooding, Assemblymen Richard Katz (D--Sylmar) and Tom Bane (D--Van Nuys) sent a letter to Gov. Pete Wilson late Monday asking that a state of emergency be declared in the San Fernando Valley, which would enable the area to receive emergency relief funds.

Rescue crews launched rubber boats to save several people who had scrambled up trees to escape their flooded cars while city Fire Department helicopters used winches to rescue other stranded motorists. Dramatic television footage showed a helicopter hoisting out two people, and then one of them falling back into the water.

Michael Ross, 36, was standing on the top of his submerged car when the helicopter lowered a rescue worker to pick him up. Ross slipped a hoist under his arm and was lifted about 100 feet into the air when he suddenly found himself falling. But the water had risen to such a level that he did not hit bottom.

“I have absolutely no idea what happened,” he said, speaking from his bed in the emergency room at Northridge Hospital Medical Center, where he was being treated for injuries that included seven broken ribs and a broken clavicle. “The look on (the rescuer’s) face was, ‘Oh, my God, what a miracle.’ He put me in a bear hug and up we went,” Ross said. “I was in a world of pain, but I’m very lucky to be alive.”

The rain triggered a host of other problems across the Southland:

* Mudslides in Malibu, Westlake Village, Agoura Hills and Ventura County.

* Snow in the mountains at the 4,000-foot level, forcing the closure of Interstate 5 at the Grapevine for three hours.

* A sewage overflow caused by swollen flood channels that prompted health officials to close all Los Angeles County beaches from the Ventura County line to Long Beach.

* Flooding that forced the closure of two colleges and five libraries in the San Fernando Valley.

* Power outages to more than 100,000 homes in Los Angeles County.

* A flash flood that swept away a car in the Pasadena Glen neighborhood below Eaton Canyon Reservoir, causing authorities to tell residents that they might consider evacuating if the rain continued.

The dramatic rescues at the Sepulveda Dam were carried out while lightning flashed and people clung to telephone pools, trees and other objects to avoid being swept away by the raging waters.

The deluge caused major commuting headaches and nearly enveloped some smaller vehicles during the evening rush hour. For varying periods of time, flooding forced closures of the Ventura Freeway at the Interstate 405 interchange, the southbound I-5 at the Hollywood Freeway and the 210 Freeway near La Tuna Canyon.

Sudden flooding forced national park rangers to close a film production set at Paramount Ranch in Agoura Hills. The film crew had to backtrack around Mulholland Drive to get to safety.

“All of a sudden a ton of water came up the creek, and the rangers told us we had to leave for our own safety,” said Tim Johnson, an associate producer with the Sullivan Co. “Things like that don’t happen too often here.”

Although the rain was expected to taper off by today, weather officials said another storm is expected to blanket Southern California by Wednesday, bringing with it several more inches of rain. Scattered heavy showers are forecast to last throughout the week, weather officials said.

“Skiers are going to be loving this weather but it’s not going to be good for commuters for the rest of the week,” said Marty McKewon, a meteorologist with WeatherData Inc., which provides forecasts for The Times. “This is a major storm and it’s going to be sticking around for a while.”

Monday’s downpour drenched the San Fernando Valley and southern Ventura County by early evening. In Woodland Hills, 6.14 inches of rain fell in 24 hours, while 4.62 inches dropped in Northridge and 3.06 in San Clarita. More than 2 inches fell in Santa Barbara while only 0.58 of an inch fell in the Civic Center and 0.24 at Los Angeles International Airport.

“It very well could have been the worst flooding we’ve had since a severe one in 1938,” said Gary Neumann, a meteorologist with the National Weather Service. “There was just a train of very intense thunderstorms moving right through the San Fernando Valley for a number of hours.”

Still, even continued rainfall will have little effect on the drought, officials said, because the seasonal rainfall level is about half of normal this year.

“It would take a tremendous, unusual event to pull us out,” said Dee Davis, a spokesman with the state Department of Water Resources Drought Center.

Drought conditions were not on the minds of many commuters, who had to cope with flash floods and treacherous road conditions.

A Los Angeles Fire Department spokesman said a van overturned in Santa Clarita near Soledad Canyon and Bouquet Canyon roads, but that everyone in it had been accounted for.

Burbank police declared all major arteries leading to the Burbank-Glendale Airport impassable about 2 p.m. because of heavy flooding, although the airport remained open. Sgt. Don Goldberg said that several businesses in the area reported collapsed roofs because of the downpour.

The drama in the Sepulveda Dam Basin unfolded at Woodley Avenue and Burbank Boulevard, just a few hundred yards west of the San Diego Freeway, about 1 p.m.

John Mittendorf, a battalion fire chief, told reporters that when the river went outside its banks, “numerous people were suddenly caught . . . in their cars.” He said firefighters who tried to rescue them from the ground also were trapped, forcing helicopter teams into action.

County firefighters used ropes to rescue stranded motorists whose vehicles were nearly submerged by water on Sand Canyon Road in the Santa Clarita Valley, and officials closed a four-mile stretch of the low-lying road lined by small ranches, said Inspector Robert Lockett of the Los Angeles County Fire Department.

“They saw the road was flooded and figured they could get by anyway, but they learned their lesson,” Lockett said of the motorists.

More than six miles of streets, including parts of Sand Canyon, Placerita Canyon and Newhall Ranch roads, were closed by midafternoon in Santa Clarita because of flooding, authorities said.

Officials said the roads would be reopened to allow only residents to make their way home once the rain let up.

Topanga Canyon Boulevard was shut down and declared impassable about 2 p.m. because of rockslides, mudslides and flooding, authorities said.

Lightning and rain knocked out power in several parts of the county. About 80,000 DWP customers in the northeastern San Fernando Valley lost power about 2 p.m. when lightning struck a generating station at 9430 San Fernando Road.

The Daily News newspaper and several other companies clustered in Warner Center in Woodland Hills, including Kaiser Foundation Hospital and Litton Industries, lost electricity about 11:30 a.m. when lightning struck a high-voltage power line in the area.

Power was restored within an hour to all but the Daily News, whose electrical wiring was directly hit, said Dorothy Jensen, a DWP spokeswoman.

Flooding problems also forced California State University, Northridge, and Pierce College in Woodland Hills to close for the day. Five branches of the Los Angeles Library in the San Fernando Valley were closed by midafternoon because of flooding and power outages, said spokesman Bob Reagan. The branches were in Sun Valley, Panorama City, North Hollywood, Pacoima and Sunland-Tujunga.

In Malibu, a woman and her two small children narrowly escaped disaster when their car stalled while crossing a rain-swollen creek in an exclusive area of Malibu.

Lisa Hilton, 35, her son, Christian, 4, and her 4-month-old daughter, Fiona, managed, with the help of a neighbor, to get out of the car seconds before the surging water swept their BMW sedan half a mile downstream, where it was submerged in six feet of water, eyewitnesses said.

“The car was like a boat going down the creek,” said actor Nick Nolte, who, along with Frank Capra Jr., was among the first to arrive at the scene.

Witnesses said a neighbor waded onto the flat-water bridge and carried the children to safety and that Lisa Hilton managed to swim to shore after being swept under by the surging stream.

“She was extremely lucky,” said her husband, Steve Hilton, grandson of the late hotel scion Conrad Hilton.

The creek, which feeds into the Pacific Ocean at the mouth of Bonsall Canyon, flooded several expensive houses. The floodwaters left at least two houses on Bonsall Drive marooned, including that of rock singer Pat Benatar.

The storm buffeted the eastern half of Ventura County with more than four inches in eight hours, flooding streets and homes, causing dozens of accidents and causing the county’s flood control channel to breach its banks.

By midafternoon, Moorpark had received 5.09 inches of rain in the 36 hours since 8 a.m. Sunday morning.

“I don’t think we’ve ever seen that before in Ventura County,” said Dolores Taylor, county hydrologist.

The storm caused dozens of minor injury accidents, closed numerous county and city streets and sent mudslides oozing onto highways, closing California 33 above the resort community of Ojai.

The National Weather Service issued an urban and small-stream flood advisory, urging motorists to use caution and not try to cross flooded streets.

In Orange County, officials reported only minor problems, citing last week’s storm as the reason.

“Maybe people learned how to drive in the rain,” mused CHP Officer Angel Johnson. “They’ve had some practice recently, I guess.”

Contributing to this story were Times staff writers Leslie Berger, David Colker, Richard Lee Colvin, Ashley Dunn, Tracey Kaplan, David Wharton and Edward J. Boyer in Los Angeles; Ron Russell in Malibu, Joanna M. Miller in Ventura County, David Reyes in Orange County and Lisa Omphroy in San Diego.

Wild Weather

A fierce storm moved into the Southland, causing mudslides, flooding and road closures. The San Fernando Valley was among the worst-hit areas as flash floods created instant lakes. Among the sites affected by the weather:

A) Santa Clarita: More than six miles of local streets are briefly closed.

B) Westlake Village/Agoura Hills: Mud and water ooze into homes in the area.

C) Malibu area: Malibu Canyon Road is temporarily closed by mudslides, as is Las Virgenes Road further inland. Mud and water ooze into homes from at least one creek. Other closures due to mudslides are reported.

D) Woodland Hills/Northridge: Flooding shuts the Woodland Hills facility after the cafeteria is flooded. Roads into campus are impassable. Cal State Northridge is also closed.

E) Burbank Airport area: Entry roads are temporarily impassable.

G) Sepulveda Dam Recreation Area: The Los Angeles River spills over its banks into the recreation area/flood basin after intense downpours, inundating scores of automobiles near Burbank Boulevard and Woodley Avenue. Rescuers in helicopters pluck stranded motorists to safety.

SOURCE: Los Angeles Times, Associated Press, California Highway Patrol, Los Angeles Fire Dept.

Rough Roads

Among the freeways that were closed for a time:

* I-5 near the 170.

* 101 near Van Nuys Boulevard and the 170.

* Westbound 210 west of La Tuna Canyon.