Rainstorms hasten ground movement, erosion beneath SoCal houses

Mansions perched on the edge of oceanfront cliffs in Dana Point. Homes red-tagged across shifting soil in Rancho Palos Verdes. Mudslides hurling debris into homes in Studio City.

The river of storms sending buckets of rain across Southern California this month have caused slope collapses and shifting ground, placing homes into harm’s way, The Washington Post reported. 

With the damage from floods, mudslides, sinkholes and coastal erosion has emerged striking images of three mansions atop the cliffs of Dana Point — stubbornly clinging to the precipice.

Lewis Bruggeman, owner of the multimillion-dollar house nearest to the landslide, has told reporters that his house is stable despite its perilous appearance, while city officials insist the home is firmly anchored to bedrock.

But an executive with an engineering firm that inspected the property after the slide said future rainstorms are “going to continue to eat away at the slopes.”

“That’s going to need major, major work to stabilize that property,” Kyle Tourjé, executive vice president of Alpha Structural, a Los Angeles-based engineering firm that specializes in soil and structural work, told the Post.

Tourjé said his firm has responded for emergency assessments and repairs for more than 60 landslides over the past week in Southern California.

“We’re seeing more damage, and I think we will continue to see more significant damage,” he said. “Between back-to-back years of heavy saturation, these houses, these properties … they just can’t take this kind of beating.”

The rains have only speeded up the slow-moving ground movement across hundreds of acres in Rancho Palos Verdes.

The land has shifted and slumped, damaging homes and causing water and gas pipe leaks. Crews have worked to fill in fissures, while engineers have described the movement as unprecedented.

“Areas that were only moving in inches are now moving in feet per year,” Rancho Palos Verdes Mayor John Cruikshank told the Post.

The upscale city has confronted landslides for decades, but two rainy winters have accelerated the movement.

In recent months, two homes have been red-tagged — deemed unsafe for occupancy — and the city closed eight miles of trails because of safety issues from open fissures, according to the mayor. Wayfarers Chapel, a famous ocean-view wedding spot known as the “glass church,” also closed earlier this month because of the shifting dirt. 

“Clearly with that much glass above the temple area and being so precarious, you just can’t leave that open,” Cruikshank said. “That would be way, way too dangerous.”

Cruikshank said the city will ask Gov. Gavin Newsom to declare a state of emergency for Rancho Palos Verdes.

The latest storm slammed counties along the coast with more than 10 inches of rain over three days in some places, including hilly areas that have already been soaked by earlier downpours.

Alpha Structural officials said they visited the Scenic Drive landslide site in Dana Point at Bruggeman’s request. The firm said it couldn’t provide a detailed report on its assessment or recommendations for the Orange County home.

But the storms this month have left destruction far beyond Dana Point. Some 1.1 million homes across six counties have a moderate or greater risk of suffering damage from flash floods.

Tourjé blames much of the problem to development decades ago under insufficient building and grading codes. 

Residents also make problems worse, he said, by directing roof downspouts or pool runoff pipes onto vulnerable slopes. He and his colleagues have been racing to Malibu beachfront homes with the sand below them scoured away, train lines wiped out by landslides, homes knocked down, swimming pools filled with mud.

“It seems to be getting progressively worse, year after year,” Tourjé told the newspaper.

— Dana Bartholomew

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