Repairs to cost $8M take 1 year on landslide that stopped San Diego

San Clemente has authorized spending more than $8.5 million on repairs expected to take as long as one year on the landslide that stopped train traffic for weeks between San Diego and Orange counties.

City officials said they hope to start the work as soon as possible because the slope is still slowly sliding, and the historic Casa Romantica Cultural Center and Gardens at the top is in danger of falling to the railroad tracks below.

“It’s extremely tenuous right now,” said Kevin Colson, vice president of the San Clemente consulting firm LGC Geotechnical, Inc., in a presentation this week to the San Clemente City Council.

The heavily traveled coastal line is San Diego County’s only railroad link to Orange County, Los Angeles and other points across the United States.

Casa Romantica was built in 1927 by San Clemente founder Ole Hanson on 2.5 acres that today is owned by the city. Soil samples show the buildings are constructed on sand that became saturated with water during the unusually heavy rains of the past winter.

“It’s teetering on failure, in simplified terms,” Colson said. “We have two clay beds dipping out of the slope that are extremely weak. There’s water in there. It wants to keep moving.”

The City Council voted unanimously to approve emergency contracts with LGC Geotechnical for consulting and with Alliance Diversified Enterprises, Inc., of Escondido for construction “immediately to secure the building and site to protect life and property prior to the upcoming winter rain season.”

The work will involve installing four sets of “tiebacks” or anchors drilled horizontally 100 feet into the slope from top to bottom to reach the layers of clay and bedrock beneath the sand.

The tiebacks will be connected to a concrete wall at the surface that will be covered with soil and a reinforcement fabric called a “geogrid,” and then landscaped when the stabilization is finished.

Money for the work will come from delaying for a few years a planned capital improvement project, construction of the city’s Mariposa Beach Trail Bridge replacement, said Kiel Koger, public works director and city engineer. That project was budgeted for $8 million. Meanwhile, the city will pursue state and federal grants that could cover the costs.

The stabilization project could take up to a year to complete, but the goal is to have the tiebacks installed before the winter rains begin, Koger said.

Also threatened by the slide is the Reef Gate condominium building on the slope below and slightly north of Casa Romantica. About 30 of the 72 condominiums there were evacuated for almost a month after the initial slide pushed mud and debris up against the building.

Several Reef Gate residents at the meeting Tuesday praised the city and its contractor for their response so far, and urged them to continue the work as quickly as possible.

“The approach to this is solid,” said Chuck Hartman, an engineer and long-time resident, and the work should be finished before rain activates the slide again.

Passenger rail travel resumed Monday between San Diego and Orange counties after the completion of a 12-foot-tall barrier wall along the tracks beneath the San Clemente slide, ending a suspension of nearly six weeks. During the suspension, Amtrak passengers could ride a bus to make the connection between the stations at Oceanside and Irvine.

Trains initially stopped April 27 because of the Casa Romantic landslide. Service resumed in late May after some grading and repairs, but trains were halted again June 5 after additional sliding occurred in the same place.

Before that, a different coastal slope failed in September 2021 and again in 2022 two miles south of the current trouble spot. Repairs there cost more than $13.7 million and kept passenger trains suspended for about six months.