Rancho Palos Verdes launches project to halt accelerating landslide threatening coastline

In the next two months, Rancho Palos Verdes city officials hope to have a major multi-million dollar project underway to slow the landslide that's been so challenging to this community and now moving faster than ever toward the ocean.

Geologists say the coastline along Rancho Palos Verdes is changing. There's new shoreline where the sea-level is meeting the land.

"It's just rocks coming out of the water," said geologist Mike Phipps.

Those rocks are actually the landslide that has been creeping down this community since the 1950s proving a challenge to homeowners, businesses and churches, like this Wayfarers Chapel that recently had to pack up and move from its facility because of ground movement.

"It’s moving the slide more oceanward from what it used to be," Phipps said. "The base of the landslide is ramping up in what used to be the surf zone."

The superhero in all of this might be devices called hydraugers. What they do is called dewatering which is to remove the water either from within or underneath the landslide mass, which is about 150 to 200 feet deep, and it’s like a big bathtub.

"It’s full of water within the landslide and it’s believed there is water underneath the landslide down in the beach area pushing up on the landslide," Phipps said.

City Manager Ara Mihranian says the goal is to try to remove that water and, which is not cheap. But the movement can be destructive, he said.

"We repair the road and then within 24 hours we start to see cracks," Mihranian said.

What we see down there along the coastline is a challenge. They've been dewatering for years but instead of using vertical hydraugers – they will be horizontal.

The city manager says it’s expensive! The cost? About $10 million just for the equipment, not to mention the ongoing maintenance expenses.

As we speak, there is some drilling going on to get this project off the ground. It's expected to be in full force by August 2024.