A resident wrote: “Can you look into what is (not) going on with the Asilomar stabilization and road closure project? It started almost a year ago, and it appeared that the stabilization part of things was done around mid-summer. But nothing’s happened since then.”
The repair is supposed to resume tomorrow, October 28, according to a LA City worker at the site on Friday.
Asilomar overlooks the Pacific Ocean and lies above two mobile home parks, Tahitian Terrace and Palisades Bowl. The street, between El Medio and Almar Avenues, is built on a hillside that has two landslides. One starts 90 feet below the surface, extends into the Pacific Ocean, and is considered inactive. The other, 35 feet down, is continually moving.
The City of Los Angeles installed inclinometers to measure ground movement on Asilomar in 2000.
Five years later the movement of the hill had sheared off the top of one of the inclinometers. A year later a measurement showed that the ground had moved more than a foot vertically.
The street below Asilomar, Puerto Del Mar, has disappeared, all but for the cracked asphalt and dirt that marks where it once existed.
The Asilomar slide is also complicated because the hillside is owned by three different entities: L.A. City, Eddie Biggs Estate (Palisades Bowl) and McDonald Family (Tahitian Terrace). Although the City reached out to both owners, neither are obligated to work with the City, because mobile home parks are under the jurisdiction of the state.
In 2017, three de-watering wells were installed, about 140 feet under Asilomar, between Wynola and Almar. The goal was to pump groundwater to the sewer system, thus reducing the potential for more slide movement. The City proposed to slow the slide with Deep-Soil Mixing (DSM) columns, a pilot program.
The method involves digging holes that are three feet wide, but not removing the dirt. Rather, the soil is loosened and then concrete is added. The soil and concrete are mixed, creating a solid column. The process is then repeated along the area of the slide.
Everything was on hold during Covid. Then about a year ago, Asilomar became the site of DSM. During that time the street was closed to through traffic – except for residents. One of the lanes on the two-lane road is still closed, inaccessible to several streets that feed into Asilomar.
On October 1, Michael Womack, with the L.A. City Geotechnical Engineering Division, sent a letter to Pacific Palisades Area 4 representative Karen Ridgley, which she shared with CTN.
Womack said the Deep Soil Mixing Columns that the contractor installed were tested and were found to be considerably stronger than they were designed for. “This is great news and may result in eliminating the need for the dewatering wells altogether,” he said.
“In a few locations along the north side of Asilomar there is very wet material and oftentimes ponding water. This causes an issue as we have to reach a certain compaction percentage of the material before we can place our base material and then pave.
“It is extremely difficult to compact wet/saturated soil,” he said. “We have located the source of the water and are working on the best course of action to reach the compaction percentage requirements.”
City workers also found some underground utilities were damaged. Womack said that some of the dewatering wells were not working properly
The city worker onsite on Friday said that excessive watering at homes near Asilomar was causing the pooling and he asked to get the information out, so people would stop watering for a while. “The dewatering wells are working,” he said. Nearly all of the water on the El Medio mesa drains downward to Asilomar.
The worker said the city planned to remediate the wet dirt by removing it, starting tomorrow, October 28. One the dirt is removed, rocks will be put down and then a slurry poured over it, and finally the road will be repaved. “We hope to have the whole project done by Thanksgiving,” he said.
Thank you so much for looking into this. It has gone on forever and none of us
Are told anything. Again thank you.