Destroyed homes and collapsed power lines have peppered a section section of Los Angeles County coastline that is rapidly merging with the ocean, prompting an emergency declaration, a buyout program for property owners and an alarming study from NASA.
A new report from NASA's Jet Propulsion Laboratory in Southern California sheds more light on the situation in the Palos Verdes Peninsula, a region along the Los Angeles County coast that juts into the Pacific Ocean and is home to the affluent Rancho Palos Verdes community. It sits about 30 miles south of downtown Los Angeles.
The report found that the region, long understood to be an extremely landslide-prone part of the state, moved by 16 inches toward the ocean during a four-week period last fall, when researchers used radar during aerial flights to measure the movement. That's a rate of about 4 inches every week.
Though slow-moving landslides have been a fact of the area for decades, the researchers determined the landslide-prone area has expanded. Record-breaking rainfall in September 2023 and heavy rain in early 2024 caused an acceleration.
"(T)he speed is more than enough to put human life and infrastructure at risk,” Alexander Handwerger, who performed the JPL analysis, said in a news release.
The land is moving about 80 times faster than it was in October 2022 and the active area of the landslide complex has expanded from just under 400 acres to 700 acres, according to the city of Rancho Palos Verdes. Still, there isn't believed to be a risk of a sudden catastrophic landslide event, the city said. Last year, the city said some of the landslide area had moved 10 inches in one week.
How the creeping landslides forced people out of their homes
The JPL radar flights were conducted from Sept. 18 to Oct. 17, which is shortly after Gov. Gavin Newsom declared a state of emergency in Rancho Palos Verdes because of disrupted utility services, including electricity and gas. The region's electricity company told residents that recent land movement was creating unsafe conditions for residents.
"The ground movement affecting your neighborhood has created unsafe and hazardous conditions, which have already impacted SCE's infrastructure, causing power poles to lean and power lines to fail," Southern California Edison said in July 2024. “The impact on SCE's equipment caused by these hazardous conditions increases the risk of system failure, fire ignition, or other public safety hazards.”
The next month, a collapsed power line sparked a small brush fire. More than 200 homes and businesses had power turned off by early September with the hopes of restoring power as soon as possible. Southern California Edison said last month that it would be working to restore power in parts of Rolling Hills and Rancho Palos Verdes, both part of the Palos Verdes Peninsula.
Later in the fall, residents in the Greater Portuguese Bend neighborhood heavily impacted by the landslides were offered a voluntary buyout to the tune of $42 million by the Federal Emergency Management Agency and the California Governor's Office of Emergency Services, according to the City News Service. Rancho Palos Verdes expects 23 properties to be part of the buyout, the city said this week.
Contributing: Anthony Robledo and Christopher Cann, USA TODAY; Paris Barraza, the Palm Springs Desert Sun