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Joint Field Trip a Step Toward Bridging Landslide Fissure

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The Rancho Palos Verdes and Rolling Hills city officials wore casual jeans and sensible shoes. Some carried cameras. One even toted a small tape recorder to keep notes.

And after vans carried them on a whipsaw ride down a rutted roadbed better left to horses, they found themselves on the hillsides where the Palos Verdes landslides began--and where they are still going on, fed by water that causes subsurface clay to become as slick as ice.

“That’s the head of the Portuguese Bend slide,” said geologist Perry Ehlig, pointing to a mass of dirt that Los Angeles County workmen dumped while grading for an extension of Crenshaw Boulevard. “That dirt, added as fill on soft clay, triggered the slide.”

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That was in 1956, and the rough roadbed is all that remains of the plans to take Crenshaw through Rancho Palos Verdes to the sea. They were abandoned after the landscape began its slow slide to the shoreline.

Looming above, a short hike away, was Paintbrush Canyon, a steep and narrow joining of two ridges where debris from Rolling Hills’ 5-year-old Flying Triangle landslide is accumulating, looking as if a giant dump truck had suddenly turned loose tons of loose soil and rock.

“This is the edge of the slide,” said Ehlig, pointing out the fresh cracking in an area he said is moving at about two-tenths of an inch a day. “The canyon wall is acting as something of a wedge, holding it.”

For council members and staff from both cities, the field trip was a chance to see firsthand what often is the subject of items on their council agendas.

“It’s all you wanted to know about slides and then twice as much,” said Rancho Palos Verdes Councilman Robert Ryan as the group made its way along a crevice ever-widening because of land movement and runoff water.

Ehlig, Rancho Palos Verdes’ slide consultant, served as guide, although his antelope-like leaps across slide-squeezed ridges sometimes left most everyone else behind.

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In a meadow at the top of Paintbrush Canyon, the group walked cautiously, lest a small slide fissure concealed in tall grass swallow someone’s leg up to the knee.

At one point, a slight depression in the soil marked the very top of the slide, and a narrow crevice climbed right up to the backyard of a white, tree-shaded house. But only a short distance away at the top of the canyon, where a chunk of land had fallen away leaving a 10-foot cliff, the effects of the slide were more striking.

“That all let loose six or eight weeks ago,” said Rolling Hills Councilwoman Ginny Leeuwenburgh.

Down below, not far from the fields along Palos Verdes Drive South where some of the best strawberries around are said to grow, the group walked across the Portuguese Bend “moonscape,” so-called because of the barren land, small slide fissures and broken pieces of sandy-colored rock--the famous Palos Verdes stone found in countless walls and homes across the Peninsula.

On the lighter side of things, a stop at an isolated archery range prompted Rancho Palos Verdes Councilman John McTaggart to pose in front of a target with arrows he placed on either side of his head.

But not long after he walked away, three real arrows shot from the bow of an archer embedded themselves in the target, sounding just like three good slaps.

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“I didn’t think it would bother you,” the archer said to some startled members of the group.

Charles Abbott, who is public works supervisor in Rancho Palos Verdes and the man in charge of the effort to stabilize the Portuguese Bend slide, called the morning jaunt “educational.” But the officials also used it as an opportunity to start to end their war of words over dealing with the Portuguese Bend and Flying Triangle slides, which are geologically separate but which some experts believe affect each other because they are so close.

“We have got to make this one project,” said Tom Heinsheimer, the mayor of Rolling Hills. “It can’t be two.”

Douglas Hinchliffe, Heinsheimer’s counterpart in Rancho Palos Verdes, said he would welcome joint action, explaining that his city tried to solicit Rolling Hills participation in the redevelopment agency formed in 1984 to slow or halt the Portuguese Bend slide.

Heinsheimer said the boundaries of the agency might be extended into Rolling Hills to take in all of Paintbrush Canyon through negotiations with Rolling Hills property owners and the community association, which controls that city’s private road system.

“It can be negotiated and as a result of this tour, discussions should be undertaken,” Heinsheimer said.

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Utilizing $2 million in state funds, the agency intends to step up efforts to control the Portuguese Bend slide--spending $750,000 alone for drainage systems in Portuguese Bend and at the city boundary at the bottom of Paintbrush Canyon. The city is putting the emphasis on drainage because too much water is still accumulating in the slide area, and Abbott said he wants the drainage pipe to go to the top of the canyon--something that will require the involvement of Rolling Hills.

Rancho Palos Verdes recently angered its neighboring city when it sent form letters placing Rolling Hills “on notice” that the Flying Triangle slide threatens stabilization efforts in Portuguese Bend.

Heinsheimer called the letter “adversarial” and “bizarre,” but Hinchliffe said it was a good move: “It made something happen.”

McTaggart said he hoped the field trip marks “a burying of the hatchet and the beginning of working together.”

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