A landslide over the weekend ripped luxury homes off their foundations in Southern California, prompting a dozen properties that were at risk of falling down a nearby canyon to be evacuated.
The landslide began Saturday in Rolling Hills Estates, California, an affluent and mostly residential city about 27 miles south of Los Angeles. Residents then noticed cracks appearing in structures and the ground.
Los Angeles County Fire Department officials red-tagged twelve homes as unsafe, displacing 16 residents who were only given 20 minutes to evacuate. While evacuation remained limited to the 12 homes on Monday, Assistant City Manager Alexa Davis said 10 were still actively moving and another 16 were being monitored.
The pace of the land movement climbed through the weekend and into Monday. Janice Hahn, chair of the Los Angeles County Board of Supervisors, said Monday afternoon that the land had moved 20 feet since the day before and homes had completely collapsed into the canyon.
“It is moving quickly,” Hahn said. “You can actually hear the snap, crackle, and pop every minute when you’re there as each home is shifting, is moving.”
Rolling Hills Estates has activated its emergency operations center and the city council said it will declare a state of emergency. The city said it is also working with Los Angeles County agencies and the Red Cross to monitor the area and to provide shelter for displaced residents.
Heavy rains suspected in landslide
On Monday, numerous homes were seen with significant damages, including collapsed roofs, shattered walls, tilted chimneys, and decks hanging over the adjacent canyon. The Los Angeles County Fire Department shared a video on Twitter showing the destroyed homes and cracked ground.
Although the cause of the landslide is not yet known, Hahn said a fissure was found running among the homes which raised suspicion that the heavy rains from winter storms earlier this year may be the cause.
“We won’t know until a geologist and a soil expert really does a post-op on this and tells us what happened,” Hahn said. “But because of that fissure, the initial thinking is that it was because of the heavy rains that we had last year and all that underground water has caused this. But we don’t know.”
Displaced residents met with officials Monday for updates and assistance, according to Hahn. Los Angeles County Fire Chief Tony Marrone told residents their homes were too dangerous to enter.
Many were unsure if they were insured for the incident, including one who moved in two months ago after escrow closed, Hahn said. Los Angeles County Assessor Jeff Prang advised residents to apply for property tax waivers and said his office was working to reassess the value of the impacted properties.
California susceptible to landslides
According to the U.S. Geological Survey, California is well known to be vulnerable to landslides. Destructive landslides have previously occurred across the state, including on the Palos Verdes Peninsula, which sits high above the Pacific Ocean on the county’s south coast.
In 1956, 140 homes were damaged and destroyed in the Portuguese Bend area of the city of Rancho Palos Verdes, and the ground continues to move in the area. The landslide coincided with the construction of a road through the area, which is atop an ancient landslide.
And in 2011, a landslide severed the blufftop ocean road near White Point in the San Pedro section of Los Angeles several months after engineers began noticing cracks and fenced off the area for study.
Southern California’s complex landscapes contribute to landslides, according to an overview by the USGS in conjunction with the California Geological Survey. Landslides in California generally occur due to precipitation but many other potential factors include earthquakes, steep slopes, and sedimentary soil that is not rock hard, according to the USGS.
But human actions can also induce landslides, such as construction without proper grading of slopes, alteration of drainage patterns, and disturbances of old landslides.
Contributing: Associated Press
