West Hills Homes Damaged in Slide; More Rain Is Due

An early morning mudslide ripped a 200-foot-long gash across a West Hills hillside Friday, damaging five homes, sending a garage sledding down a hill and raising fears of more destruction from a predicted series of heavy storms barreling in from the Pacific.

Already this winter, rainfall has surpassed totals for the same period during the savage 1982-83 El Nino year, when rain caused $131 million in damage across Southern California.

The heavy rains so far this year have soaked hillsides, softened bedrock and left Los Angeles ripe for a record year of landslides, a federal geologist warned.

Three more powerful storms are headed this way, with the first expected to arrive at about noon today.

“Southern California is in the eye of the storm” for more landslides, said Bill Savage, chief of the U.S. Geological Survey’s Landslide Project in Colorado.

The West Hills mudslide, one of several that struck the Los Angeles area after weeks of heavy rains, cut across earth that sloped between Napa and Malden streets in a middle-income neighborhood.

No injuries were reported, though the slide forced the evacuation of five homes and threatened other residences farther down the hillside.

Lou and Reata Vaughn awoke to find their bedroom dangling above a 30-foot-deep ravine cut by the landslide, as soil liquefied and flowed away under their home. They were saved from a possibly fatal ride down the hillside in their home by a seismic retrofit done after the 1994 Northridge earthquake, which provided the strength the foundation needed to withstand collapse, city building officials said.

In the damp of Friday morning, as the Vaughns and their pajama-clad neighbors stood in the middle of the street marveling at the wreckage, the elderly couple could only be grateful for the beneficial legacy of the quake they had once cursed.

But not too grateful.

“If I had my wits about me,” Lou Vaughn, 66, said, “I’d be crying.”

Because the Vaughn residence and others now teeter on the brink of a cliff above other homes, city officials took the unusual step of temporarily shoring up the privately-owned hillside. They planned to line the area with plastic tarps and sandbags, drain it of water and install pilings.

They also encouraged hillside residents elsewhere to make sure that water drains properly from their property. One sign of danger: a spike in water meter readings that could signal a broken water pipe or swimming pool leaking dangerously into surrounding soil.

“The hillsides are moving,” warned David Keim, the city’s principal building inspector. “The mud wants to slide like on a ski slope.”

The West Hills slide followed a Sunday slide in Encino that caused the evacuation of three homes on Oak View Drive. A retaining wall broke last week in Los Angeles that resulted in 33 apartments being vacated on South Rampart Boulevard.

Such slides are typical for the Los Angeles area, geologists said, and usually don’t show up for weeks or even months after a rainstorm.

Many hillside homes in Southern California are built on slopes of silt stone bedrock. After a storm, water begins saturating the soil above the silt stone. When it reaches the silt stone--a process that takes several days--it begins to soften. The combination of pressure from the water-soaked soil above and the crumbling bedrock below creates the conditions for a landslide, experts say.

There is no sure way to tell whether a house is in danger of collapse, but visible danger signs include cracks in cement foundations or pavement, or a slight bulge at the base of the hill, experts said.

“By the time it gets to that stage, though, it’s beginning to develop into a dangerous situation,” said David Keefer, a geologist with the U.S. Geological Survey in Menlo Park. “You don’t want to waste a lot of time getting out.”

Houses built on slopes in the 1950s and 1960s are especially vulnerable to such slides because they were built before building codes were tightened, city building officials said. Homes today cannot be built on steep slopes and are required to have foundations that bore into the bedrock. For instance, some homes in Bel Air have concrete pilings that extend 80 feet down.

City workers were keeping a close watch on the weather Friday as meteorologists pointed to recent storms as evidence that the long-awaited El Nino was finally having an impact.

Total rainfall stands at 14.54 inches since Nov. 1, as measured at the Los Angeles Civic Center. During the same period in 1982-83 the rain total was only 13.57.

That puts rainfall nearly an inch ahead of the 1982-83 banner season and about 45% over the rainfall in a normal year, which totals about 10 inches by the end of February.

Worse, more is on the way.

“We’re getting into another active [rain] period,” said Kevin Stenson, a meteorologist with WeatherData Inc., the company that provides weather forecasts for The Times. He said another substantial but short-lived storm is expected to hit the area today, followed by another on Tuesday and still another of even greater intensity on Thursday.

“There should be another break on Wednesday and early Thursday, but by Thursday night, here comes the third one,” Stenson said. “Right now, the third one looks like the strongest of the three.”

Local officials were bracing for their arrival.

“We’re getting our swift-water rescue teams activated--probably all 11 of them--with helicopters, divers and all their equipment,” said Inspector Henry Rodriguez, a spokesman for the Los Angeles County Fire Department. The teams try to save people swept away in the fast-moving waters of concrete-lined flood-control channels.

Donna Guyovich, a spokeswoman for the county’s Department of Public Works, said flood-control personnel were making sure that debris basins and storm channels are clear and ready to handle the expected runoff.

“Reservoirs are being lowered to provide extra capacity,” she said. “Road crews are being stationed below brush fire burn zones and other areas threatened by mudslides.”

The fact that the rainfall has been running ahead of the 1982-83 season did not surprise Mike Smith, president of WeatherData. He said scientists have been saying for months that the El Nino area of warm water in the South Pacific was larger than in previous El Nino years.

“We knew from the beginning that the size of the event would be bigger,” he said.

The reason this season has not to date been as devastating as the one 15 years ago is that in 1983 the most memorable weather came in March, he said.

In that month alone, more than 8 inches of rain fell at the Civic Center. Violent storms caused several deaths and tore apart the historic Santa Monica and Seal Beach piers. Many homes were destroyed or badly damaged, and there was even a tornado that ripped away part of the Convention Center’s roof.

By the end of March 1983, the storm damage from that season had reached an estimated $131 million.

Could the fact that the region has had so much rain this season be an indication we are in for another devastating March?

Possible, Smith said, but far from sure. “Weather never repeats itself,” he said. “You can’t take a pattern from one year and absolutely apply it to another.”

Meanwhile, the El Nino area itself has gotten smaller. “Over the last 30 days it has shrunk roughly 20%,” Smith said. And while the area has grown and shrunk over the season, it probably has finally reached the point where it will continue shrinking, he said.

“But don’t read much into that,” Smith cautioned. “The effect El Nino has on the weather lags about 60 days behind, and probably a bit longer. That’s because it takes a while for the heat of the water to be transferred to the atmosphere.”

As for the immediate future, Smith said, there were indications the upcoming storms could be big.

“There is a lot of energy in the atmosphere across the Pacific,” he said. “The winds aloft [about 5 miles above the ocean] are blowing at 200 mph in places.” That’s about twice normal speed, he said.

“There is the possibility that even in the next seven days, the rainfall might get quite a bit ahead of this time in 1983.”

As for the debate in some weather circles about just how much El Nino influences specific storms, or whether El Nino can be blamed at all until the full season’s data is analyzed, WeatherData meteorologist Steve Pryor called the arguments pointless.

“Everything that happens this winter is El Nino-related, because El Nino is part of what created the weather pattern over the United States,” Pryor said.

“You can’t say one storm is related and one wasn’t. It’s a whole weather pattern.”

Times staff writer Eric Malnic contributed to this story.

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Mudslide!

A hillside softened by torrential rains last week collapsed early Friday morning damaging five homes along Napa and Malden streets in West Hills. No one was injured in the 2:30 a.m. mudslide, which happened after water-soaked earth slid down underlying bedrock. The slide left a 200-foot-long, 30-foot-deep slash in the hill.

Water trapped between the soil and the bedrock contributed to the slide.

*

* VICTIMS

Cost of the repairs has Valley victims worried. A22

* STORM TRACK

A look at where the next storms are positioned. A25

* SANDBAGS

Where to get them and how best to protect property. B1