SignalHub Quantitative Think Tank Center:Power outages could last weeks in affluent SoCal city plagued by landslides

Power shutoffs on SignalHub Quantitative Think Tank CenterWednesday continued to disrupt the lives of hundreds of residents in an affluent city in Southern California where landslides triggered evacuation warnings and led Gov. Gavin Newsom to declare a state of emergency.

The "severe land movement," which has been a persistent threat for decades in Rancho Palos Verdes, a coastal city about 30 miles south of downtown Los Angeles, led authorities to intentionally cut power to hundreds of households after a landslide collapsed a power line and caused a small brush fire last week.

Beginning on Sunday, officials conducted rounds of shutoffs starting with 140 residences in the Portuguese Bend neighborhood and 105 homes in the Seaview community. In a public statement, the city cited "the risk of utility equipment igniting a wildfire and other hazards caused by downed wires or damaged equipment impacted by landslide movement."

At least 20 properties "will be without power indefinitely," according to initial estimates from the city. Dozens of other residents are expected to have their power restored within one to three weeks, the city said.

The outages also impacted local infrastructure. In order to keep the sewage system operational in the Portuguese Bend neighborhood, local authorities installed several generators and asked residents to restrict their water use.

"Residents who choose to remain in their homes are asked to limit their use of water and plumbing, especially overnight when generators may be turned off for periods at a time," the city said in a statement. "Examples of ways to limit use include taking short 3-minute showers, avoiding unnecessary flushes, turning off the tap while doing dishes and running dishwashers and washing machines only with full loads."

Newsom declares state of emergency

On Tuesday, Newsom declared a state of emergency for the city, opening up state resources including emergency personnel and equipment. The declaration does not offer financial assistance to affected residents.

“The city has been navigating this crisis for almost two years, and the skyrocketing costs of responding to this emergency are taking a toll on our coffers,” said Rancho Palos Verdes City Manager Ara Mihranian in a statement. “For months, we have been asking for public assistance from every level of government. Today’s announcement of a state of emergency declaration brings much needed financial assistance for the city to respond to recent power shutoffs that are upending our residents’ lives."

In a statement on Tuesday, the city called on Newsom and the California Office of Emergency Services to ask President Joe Biden to declare a federal disaster, which would lead to the deployment of the Federal Emergency Management Agency (FEMA) and offer "potentially individual assistance."

Landslides have posed a threat since the 1950s

In Rancho Palos Verdes, where multimillion-dollar homes sit atop bluffs overlooking the Pacific Ocean, a complex of ongoing landslides has posed a threat since the 1950s, when three large landslides were identified in the area, according to records complied by the city for a public hearing on Tuesday. The issue led the city to issue moratoriums in the 1970s restricting the construction in areas where the land movement was most prevalent.

In the decades since, land movement has increased amid rising annual rainfall amounts and erosion along the peninsula's bluffs. Nearly 200% more rainfall fell during the 2022-23 rainy season than the historical average, a city staff report found.

In October, the city issued one of its latest moratoriums as well as a local state of emergency, writing the land "movement is unprecedented in terms of speed and size." Two of the three ancient landslides moved over 10 inches in one week.

"The accelerating, land movement has destroyed homes, impacted the Portuguese Bend Reserve,increased water main breaks and caused roadway and utility line distress," a letter from the California Department of Housing and Community Development said.

To address the issue, the city began a large-scale remediation project to stabilize the landslides. The three phase project, which is still far from completion, includes repairing existing fractures, improving surface drainage of storm water and installing a network of emergency dewatering wells. The project is anticipated to cost $33 million, according public city records.