Massive Earthmoving Project Planned for Portuguese Bend : New Slide Plan--If You Can’t Beat It, Move It

If everything goes according to schedule, large earthmovers will begin this summer to shift tons of dirt off the Portuguese Bend landslide that is moving closer to the sea.

By the city’s own admission, this opening shot in a two-year, $2-million attack on the slide is an experiment that may slow or stop the relentless landslide that, over nearly 30 years, has destroyed more than 130 homes and blanketed a large swath of land--popularly know as the moonscape-- with ripples of undulating earth.

“We’re ready to go from the engineering standpoint,” said Charles Abbott, city public works consultant and the man in charge of the landslide stabilization project. “We’re ready to advertise for bids to move some dirt.”

In all, 400,000 cubic yards of soil--40,000 truckloads--will be shifted over a three-month period from the slowly moving earth slide to an area below. The intent is to take pressure off the subsurface slide plane, where the earth is moving, and to create a stabilizing mass below.

“We will take away the driving force that is causing the land to move and create a force to cause it to stop,” Abbott said.

He described what is contemplated as a trial-and-error venture into a new area of landslide technology.

“No one has ever moved an earth mass around in the middle of a slide,” he said. “Buttresses are common methods, but we don’t have a common slide.”

He said a panel of 17 geology experts who have been working with the city on the slide project has given the city “a 100% chance of slowing the slide and an 80% chance to stop it.”

The first phase of the stabilization project also includes installing a drainage system in Paintbrush Canyon, on the east side of the slide area, to carry runoff water to the ocean. “We are looking to take care of average rainfall, to get water off of the slide plane,” Abbott said.

Geology experts have concluded that the continuing land movement is the result of accumulated rainwater percolating down to the slide plane, which is composed of a volcanic material called bentonite. The moist bentonite provides a slick surface for the earth to slide on.

There already are wells in the slide area that pump underground water to the surface. Additional wells may be put in as part of the stabilization program.

Both the $350,000 earth-moving operation and the $210,000 Paintbrush Canyon drain are scheduled to be completed by the end of October.

The overall slide program, due to extend to 1988, also will include a drainage system in Portuguese Canyon on the west side of the slide area, additional grading and filling to reduce land movement and the reconstruction in 1987 of Palos Verdes Drive South through the slide area. Over the years, the roadway has slid as much as 600 feet southward, and it would be put back in its original right of way on land that the city believes can be stabilized.

But nothing will start, officials said, until the city has received the $2 million in landslide money--or is assured that it is on its way.

Offshore Oil Funds

The money was appropriated as a grant by the state Legislature last year. But the source of the money is a federal escrow account stemming from a settlement between the federal government and seven states, including California, over sharing oil royalties from offshore federal waters. Distribution of the money is contained in a congressional budget reconciliation bill that has yet to go to President Reagan for his signature.

James Burroughs, an aide to Sen. Pete Wilson (R-Calif.) specializing in energy issues, said he believes California will get the money, but he does not know when. Burroughs said he hopes the bill goes to Reagan by March 1, although it could be later.

City Manager Donald F. Guluzzy said it will take the state controller’s office 60 days to get the money to Rancho Palos Verdes after it has been received from the federal government. “If the President signs the bill, we might be able to go ahead and proceed, as long as we know the money is coming,” Guluzzy said.

The project will be administered by the city Redevelopment Agency, which is made up of City Council members and was formed specifically to undertake the Portuguese Bend landslide stabilization plan.

With the city gearing up for the work, a town hall meeting on the plan will be held Wednesday at 7:30 p.m. at Ladera Linda Community Center, 32201 Forrestal Drive. Officials said the purpose of the meeting is to outline the plan and work schedule for the public and to receive comment from residents.

“Without this, as we get into each individual contract and project, we would not have presented the overall picture,” said Councilwoman Jacki Bacharach. “We want to bring everyone up to speed.”

Program Could Be Criticized

The meeting could draw critical comments from a handful of residents who do not believe the stabilization plan will work, opposed creation of the Redevelopment Agency and object to renewed building in the vicinity of the slide.

Since 1978, there has been a building moratorium on about 1,100 acres in the vicinity of the active slides in Portuguese Bend and neighboring Klondike Canyon and Abalone Cove. The moratorium would have to be lifted to allow new construction.

Mayor Douglas Hinchliffe said no new construction would be permitted in what is now the active slide area even if it were stabilized, but he added, “geologists say that any part that did not slide is suitable for development. The city would allow that to be developed in accordance with general-plan zoning, which is one unit to the acre.” He estimated that up to 450 homes could be built.

Councilman Robert Ryan, however, said he does not foresee homes going up because of land stability questions. “A lot of the area in the moratorium is ancient slide area and I can’t ever see letting people build there. There is a probability it could go.”

Homes Could Be Razed

Hinchliffe said the relocation of Palos Verdes Drive South could become an issue at the town hall meeting because the project necessitates removing or demolishing two, and perhaps four, homes that have slid into or near the old right of way over the years.

“It is not the desire of the city to throw anybody out of their homes,” Hinchliffe said, “but the reality of it is that somebody probably is going to have to, at a minimum, relocate their homes. We want to see some other arrangements made to permit all of those people to go on living in the area.”

Hinchliffe said one possibility is to move the homes back to their original sites “on the assumption that no one else’s house is there.”

The massive grading would be on property owned by Palos Verdes Properties, the major landowner in the Portuguese Bend area. Abbott said the city is getting easements to do the work, which will require the temporary relocation of the five-acre Ishibashi farm immediately north of Palos Verdes Drive North. The farm leases land from Palos Verdes Properties.

Abbott said the city is talking to the Palos Verdes Peninsula Unified School District about putting the farm--best known for its strawberries--on vacant school property east of Portuguese Bend. The Ishibashi farm would eventually return to its present location after land stabilization has been completed, Abbott said.

No Threat to Stability

He said that despite the water-driven nature of the slide, renewed farming would not threaten land stability because Ishibashi uses a drip irrigation system that prevents pooling. “It is water accumulating and getting down to the slide plane that hurts us,” Abbott said.

The city wants neighboring Rolling Hills to join in the slide stabilization project because that city’s Flying Triangle landslide is above Portuguese Bend.

Rancho Palos Verdes officials are concerned that slide material and runoff water from the Flying Triangle, if left unchecked, could clog the Paintbrush Canyon drainage system.