Concern over newly shifting Palos Verdes Peninsula ground brings out hundreds for town hall meeting

 

An estimated 400 people — combined from both online and in person participants — turned out this week for the much-anticipated town hall meeting on the alarming uptick of land movement across parts of the Palos Verdes Peninsula.

The expanding territory is now, one geologist said, creating a “monster” of a landslide that is moving “at a very good clip.”

Hosted by the city of Rancho Palos Verdes, the more than three-hour meeting at the Ladera Linda Community Center Wednesday night, April 17, the town hall featured a long list of speakers who covered everything from the long history of land movement on the peninsula to what is being done to address the dangers.

The meeting’s goal?

To provide the community with a full picture of the area’s active landslides following two years of heavy rains and what is being done to combat and slow the damage — all in one place. Four landslide complexes undergird the Palos Verdes Peninsula where new movement in the past couple years is leaving homes damaged, a major roadway buckled and causing popular hiking trails to be closed.

Among the major casualties is Wayfarers Chapel, a much-beloved 70-year-old glass-and-redwood sanctuary and popular wedding venue that has seen extensive damage. It is now closed to the public and a future move to a new location is being weighed.

Wednesday night’s meeting featured speakers who provided phone numbers and other information in hopes residents will be quick to report issues they spot on their own properties or elsewhere.

A video of the meeting and other information, including contact numbers, shared — along with audience questions and answers — will all be posted on the Rancho Palos Verdes land movement web page. It may take some time to display all of the many written questions the panel members received. The meeting also will appear on the RPV TV’s YouTube channel and at @rpvchannel33.

All of it, said Rancho Palos Verdes City Manager Ara Mihranian who hosted the meeting, will require considerable funding.

“What’s happening now is much larger than what the city can imagine,” he said.

In recent action:

–Over the weekend, President Biden declared a Major Disaster for the area opening up federal assistance to assist;

–On March 19, the RPV City Council approved moving forward with emergency measures designed to slow the accelerated movement in the landslide complex, including installing two emergency dewatering wells — known as hydrangeas — to remove water that is trapped underground and contributing to the slides;

–Construction contracts for the hydrangeas were set to be considered at the April 16 City Council meeting but more time was needed, officials said to finalize the project design and the item now will be heard at the May 7 meeting; and

–Discussions also are underway with state and federal officials that would allow federal assistance to be available to individuals, not just public agencies.

Providing a history and overview during the town hall, Mike Phipps, principal engineering geologist at Cotton, Shires and Associates Inc., said the four historic Portuguese Bend Landslide Complex slide areas once “covered about 380 acres.”

“The area that is moving now,” he said, “is much larger, 675 acres. This is a monster of a landslide we’re dealing with and it’s moving at a very good clip.”

Later he added, “I think there’s a risk this thing could get bigger than it already is.”

Within the overall slide area are the Abalone Cove Landslide, the “Flying Triangle” Landslide, the Klondike Canyon Landslide and the Portuguese Bend Landslide.

So what happened?

Two years of heavy rainfall have taken a dramatic toll, speakers said. During the 2022-23 season, when the landslide began to move significantly, the area saw 26.3 inches of rain; in 2023-24 it now stands at 22.5 inches. Average rainfall for the Mediterranean climate area is 13.7 inches, according to information presented.

If there’s some good news, Phipps said, it’s that forecasts currently show a La Niña year for 2024-25 and a dryer season ahead.

Throughout the evening, speakers repeatedly stressed that the culprit and ongoing threat comes down to one thing, water.

And the key two-fold fix: pulling water out of the ground and preventing it from getting into the ground.

California Water Service representatives said at the meeting that they now have crews in both the Seaview and Portuguese Bend areas “24/7, traveling around the clock.”

Overall, the Palos Verdes Peninsula — which was once an island, Phipps noted — is the largest active landslide in the U.S. and the fastest moving; it’s also been the most studied in the nation going back to the late 1950s.

In the past year, various efforts to combat the ongoing slides have included:

–Drilling new dewatering wells;

–Making repairs below Palos Verdes Drive South;

–Replacing pumps and fixing multiple draining system leaks;

–Adding boost pumps to increase water pumping;

–Carrying out weekly monitoring activity;

–Putting in three applications for federal funds to line Altamira Canyon, a particular problem area; and

–Conducting weekly meetings with city officials and county utilities.

Among the challenges, speakers said, are the need for better reporting on fissures and damage that occur on private properties, which rely on reports coming in from residents and property owners. Homeowners were encouraged at the meeting to report any signs of new land fissures on their properties or cracks in their homes.

In the Abalone Cove area, where 129 homes are now considered threatened, stabilization efforts include:

–Removing ground water;

–Adding more dewatering wells and making well repairs;

–Moving the drainage system above ground and conveying surface water to the ocean;

–Fixing stormwater drains;

–Repairing known fissures in the canyon;

–Fissure management in residential areas;

–Eliminating large land depressions; and

–Filling in known fissures and working with property owners.

Steve Cummins, president and CEO at DCA Civil Engineering Group in Torrance, said the Klondike district “has been moving for a long time and there’s some serious damage.”

Broken underground storm drain lines damaged by shifting ground add to the heavy rainfall that has inundated the already unstable area, he said.

“The most important thing to take away tonight is water. Water is the enemy,” Cummins said.

“Water,” he added, “is what is driving the whole thing.”

Source: Orange County Register