History & Geology

Timeline of the Landslide

This timeline follows the landslides. For the Peninsula's wider story (the Tongva, the Sepúlveda rancho, Frank Vanderlip's 1913 purchase, the Olmsted plan and how the four cities incorporated), see Palos Verdes Life's history of the Peninsula.

• ~37,000+ years ago

  The ancient landslide forms

  Massive prehistoric sliding creates a large landslide complex on the peninsula's south flank, today called the Greater Portuguese Bend (or Ancient Altamira) Landslide Complex. It eventually goes dormant, leaving hummocky terrain later called Portuguese Bend.

• 1862–1885

  How Portuguese Bend got its name

  After the San Pedro Bay whaling station on Deadman's Island closes, Azorean captain José Machado brings shore whaling to the bend in the coastline north of the bay. For two decades, Portuguese crews row out through the surf to harpoon passing gray whales, tow them ashore, and render the blubber in iron try-pots — one captain alone producing 2,166 barrels of whale oil from 1874 to 1877. Petroleum kills the trade by 1885; the last try-pots and crumbling furnaces vanish by about 1928. The station's site — California Historical Landmark #381, marked along Palos Verdes Drive South — lies within today's slide zone, where the ground has since traveled hundreds of feet seaward: whaling gave this coast its name, and the landslide has been rearranging the ground it stood on ever since.

  History: Palos Verdes Library District · Historical Marker Database (CHL #381).

• 1948

  A beachfront paradise at Portuguese Bend

  The Palos Verdes Corporation opens the Portuguese Bend Club on 105 oceanfront acres — a private beach colony envisioned by Kelvin Vanderlip (son of peninsula founder Frank Vanderlip) with a clubhouse, restaurant, swimming pool, paddle-tennis courts, rental cottages, boating facilities, and a 485-foot pier reaching into the cove. It becomes one of the South Bay's most popular seaside destinations, hosting dances, swim meets, and tournaments. It has eight years left.

  Historic photos: Palos Verdes Library District local history collection.

• 1956

  Reactivation

  During extension of Crenshaw Boulevard, Los Angeles County crews place over 300,000 cubic yards of fill on the head of the ancient slide. The eastern portion reactivates. Roughly 130 homes are ultimately destroyed or removed in the Portuguese Bend community, and litigation against the County follows. The slide also kills the Portuguese Bend Club in its prime: the clubhouse, restaurant, and pool are destroyed as the ground beneath them breaks apart and rafts toward the sea, and the pier and beach colony's glory days end with them (a private beach club community survives at the site today). The land has not stopped moving since — over the following decades it carries the ground hundreds of feet seaward.

  The 1956 slide also breaks a water line — beginning a lesson the peninsula has relearned ever since: buried pipes and moving ground don't mix, and leaking lines feed the very slide that breaks them. In the moving area, utilities have long been adapted to flex — including water lines run above ground on flexible connections, a decades-old Portuguese Bend practice that Cal Water dramatically expanded across the complex in 2024 (see below).

• 1974

  Abalone Cove begins to move

  A second lobe of the ancient complex, west of Portuguese Bend, starts sliding — threatening homes above Abalone Cove and Palos Verdes Drive South.

• 1980–1981

  Klondike Canyon awakens; abatement districts form

  The Klondike Canyon slide begins moving near the Seaview neighborhood. Under California's Beverly Act, property owners form two Geologic Hazard Abatement Districts — ACLAD (Abalone Cove, 1981) and KCLAD (Klondike Canyon, 1981) — to fund and operate dewatering wells and drainage. Early dewatering succeeds in dramatically slowing Abalone Cove.

• 1999

  Ocean Trails: a golf hole falls into the sea

  On June 2, 1999 — weeks before the new Ocean Trails Golf Club east of the Portuguese Bend complex was to open — a slice of coastal bluff roughly 600 feet long and 220 feet wide gave way, dropping most of the 18th hole's fairway and green toward the ocean and snapping a 27-inch county sewer main, which spilled raw sewage onto the beach below. The failure occurred on a lobe of ancient landslide ("Landslide C") beneath the course; its trigger was disputed in years of litigation — the developers pointed to leaking buried pipes, others to the ancient slide plane itself. The landslide bankrupted the project, and in November 2002 Donald Trump bought the course for $27 million, rebuilt the 18th hole, and reopened it as Trump National Golf Club Los Angeles. A separate slide from the Portuguese Bend complex — but the same geology, and another chapter in the peninsula's long argument between water, pipes, and ancient slide planes.

  Background: Trump National Golf Club Los Angeles (Wikipedia) · CBS News (1999) · South Bay History.

• 2002–2009

  The Monks lawsuit: courts force open the moratorium

  The City's landslide moratorium, first adopted in 1978, barred new homes across the moving area — including "Zone 2," a portion of the ancient slide above Abalone Cove that had shown little modern movement. In 2002, after minor movement nearby, the City Council effectively froze Zone 2 development with a resolution requiring owners to prove a new home would not aggravate any existing geologic condition — a bar owners called impossible to clear. Sixteen lot owners sued, and in 2008 the California Court of Appeal ruled in Monks v. City of Rancho Palos Verdes that the moratorium as applied was a regulatory taking of the plaintiffs' property. In 2009 the City amended its code to let the "Monks lots" develop, and homes were subsequently built in Zone 2 — several owners had obtained entitlements by 2012.

  The arc closed in 2025: after the 2023–24 acceleration redrew the map of what this ground can do, Ordinance 692 permanently banned new residential construction throughout the complex — the restriction the courts had once forced the City to loosen, reimposed by the land itself.

  Case background: City of RPV — Zone 2 / Monks lots · case summary.

• 1950s–2010s

  Decades of creep and management

  Portuguese Bend creeps on — bending Palos Verdes Drive South, which the City repairs continuously. The City adopts a landslide moratorium restricting new development in the moving area, studies remediation options, and installs GPS monitoring. Movement waxes with wet winters and wanes with dry ones.

  Historic maps: the City hosts scanned geologic maps and reports on the Portuguese Bend, Abalone Cove, Klondike Canyon and Beach Club slides (maps from 1972 to 1983) on its Palos Verdes Drive South Landslide page.

• 2023

  Record rains change everything

  Historic storms saturate the peninsula. Movement accelerates across the complex; fissures open in the Portuguese Bend Reserve; the City declares a local emergency and begins winterization measures.

• 2024

  The fastest movement ever recorded

  The four slides begin moving as one broad mass across ~700 acres — in places several inches per week, with NASA/JPL radar measuring up to ~4 inches per week in residential areas that fall. The Wayfarers Chapel closes in February and is dismantled for preservation; the chapel says disassembly was completed in July. Power is cut to about 245 homes and gas to entire neighborhoods. The shifting ground also breaks buried utility lines over and over — including pressurized water mains and private service lines, whose leaks put still more water into a slide already driven by groundwater. Cal Water responds by rebuilding the system in the open: during 2024 its crews install above-ground water mains with flexible swing joints through most of the Portuguese Bend community, western Seaview, stretches of Palos Verdes Drive South, and part of the Beach Club — the pipes still visible along roadways today, where leaks can be spotted immediately and the lines adjusted as the land moves. In August the City reports that test boreholes at the south end of the Portuguese Bend slide, with samples from as deep as about 350 feet, have found movement on a deeper slide plane "which had not been previously known," moving much faster than the shallower one. The Council expands the project area to the whole landslide complex, prioritizing the deeper slide, and the City turns to deep vertical dewatering wells at the toe as a pilot; they begin pumping in September. FEMA and Cal OES announce a $42 million voluntary buyout program in October. And at the shoreline, the slide does something almost unbelievable: the advancing toe shoves the seafloor upward, raising hundreds of feet of new rocky land out of the surf below Portuguese Bend — "landslide debris... being pushed up and out of the ocean," in the city geologist's words, visible in before-and-after photos just months apart.

  The new shoreline: CBS Los Angeles (July 2024) · L.A. Times via Coastal Care. Cal Water's 2024 above-ground mains: Cal Water RPV newsletter (Feb. 14, 2025). Chapel disassembly: Wayfarers Chapel, Significant Dates. Deeper slide plane: City of RPV Land Movement Update (after the Aug. 20, 2024 Council meeting) · CBS Los Angeles (Aug. 21, 2024) · ABC7 (Aug. 22, 2024) · a 2025 conference abstract co-written by the City's consultants, listed under Science & Research in Reports.

  In August 2024, sixteen residents sued California Water Service (Cal Water), the City of Rancho Palos Verdes, the City of Rolling Hills, Los Angeles County, the Klondike Canyon Geologic Hazard Abatement District (KCLAD), Doty Bros Equipment Co., and the Rolling Hills Community Association (Andersen et al. v. California Water Service Company et al., Los Angeles Superior Court Case No. 24STCV20953). The suit claims inverse condemnation, negligence, and dangerous condition of property, among other things. It alleges that water from several sources, including ruptured pipes that took too long to shut off, inadequate private storm drains in the Rolling Hills community, and County flood-control and sewer systems, oversaturated the ground and sped up the landslides, including the Klondike Canyon Landslide. It also alleges that KCLAD was never adequately funded, insured, or staffed. These are the plaintiffs' allegations, not court findings. The City's Nov. 4, 2025 Council minutes still listed the case as pending, along with four other lawsuits to which the City is a party; its current status could not be confirmed as of September 2026. Anyone weighing a claim of their own should talk to an attorney promptly.

  Sources: PR Newswire, plaintiffs' law firm release (Aug. 23, 2024) · Patch (Aug. 22, 2024) · KNX News (Aug. 23, 2024) · City of RPV Council minutes (Nov. 4, 2025).

• 2025

  The slowdown

  Dewatering removes hundreds of millions of gallons; movement decelerates sharply. Seaview and the Beach Club effectively stop moving; gas restoration begins in Seaview; the City's $2.8M financial assistance program pays out to 223 households; seven additional wells are installed with ACLAD and KCLAD; the ~$33M remediation project moves through environmental review. In August, Ordinance 692 makes the construction restrictions permanent — no new residential construction in the complex (~400 homes and ~130 vacant lots), replacing the emergency moratorium in place since 2023.

• 2026

  Slower — but not stopped

  By early July 2026 the complex was moving 60% slower than a year earlier. Areas still moving within the active landslide boundary averaged 1.1 inches per week, and the deep dewatering wells had removed more than half a billion gallons since fall 2024. The buyout program had selected 27 homes, but the City said in July that it could not buy any until FEMA formally awarded the grants (the City announced the award on Oct. 14; its buyout page dates the award itself to September 2026; see below). In July the Council voted to continue the process of forming a third geologic hazard abatement district to cover the Portuguese Bend Landslide. On Aug. 4 it renewed the local emergencies for another 60 days and, according to the meeting's official minutes, adopted Urgency Ordinance No. 700U, 5-0, extending the September 2024 home-stabilization rules for temporary foundations and same-site temporary housing. The City had described the proposal as a two-year extension through Dec. 31, 2028; the minutes do not state the end date, and as of November 5, 2026 the City's Home Stabilization page still gave Dec. 31, 2026.

  In September the City reported that in its August survey, areas still moving within the active landslide boundary averaged 0.99 inches per week, the first time the overall average had fallen below 1 inch per week since October 2023. The Portuguese Bend slide itself had slowed 92% since just before the deep dewatering wells were installed; Abalone Cove averaged 1.29 inches per week. By the early-October survey the average was 1.05 inches per week (City, Oct. 28, 2026; see below). The City's Nov. 5 weekly report put the wells' total at about 590 million gallons (1,813 acre-feet) since September 2024. On Sept. 15 the Council renewed the local emergencies for another 60 days. A Governor's proclamation of Sept. 21, 2026 ended the separate state emergency proclaimed on Sept. 3, 2024 for land movement in Rancho Palos Verdes; the City's staff report for the Nov. 4 meeting says the City can continue to seek relaxed permitting and procurement processes as long as the Council extends its local emergency. With strong El Niño conditions forecast for the winter, the City reported on Sept. 30 that all canyon areas originally planned for winterization were substantially complete, ahead of schedule, and on Oct. 14 that all originally planned winterization measures had been completed in the first week of October, along with drainage improvements on Palos Verdes Drive South near the former Wayfarers Chapel and near Klondike Canyon; on Oct. 28 it said the measures had held up well during recent rainfall, with no pump trucks needed on Palos Verdes Drive South. On Oct. 6 the Council adopted Resolution No. 2026-78, 5-0, proclaiming a local emergency in anticipation of the 2026–2027 El Niño event, according to the meeting's draft minutes. On Sept. 29 FEMA announced approval of more than $54 million for the City to acquire and demolish 27 residential properties, a count that matches the 27 homes selected for buyouts; the City announced the formal award on Oct. 14 (below). On Nov. 4 the Council renewed the local emergencies in the landslide area and the PV Drive South motorcycle and bicycle ban for another 60 days, according to the City's Nov. 5 weekly report. In the City's RPVtv video update posted Nov. 5, 2026, City Manager Ara Mihranian says the Council approved nearly $56 million in federal grant funding on Nov. 4: more than $54 million for the voluntary buyout of 27 red- and yellow-tagged properties and $1.9 million for permanent power to the deep dewatering wells.

  Movement then sped up again, after what the City's staff report for the Nov. 4 meeting calls seven consecutive months of deceleration. On Oct. 28 the City reported that in its early-October survey (Sept. 3 to Oct. 6, 2026), areas still moving inside the active landslide boundary averaged 1.05 inches per week, up 7.6% since the early-August survey. The Portuguese Bend Landslide averaged 0.88 inches per week (up 14.8% from September to October, after a 3.6% slowdown from August to September), Abalone Cove 1.36 (up 16.7%, after a 9.5% slowdown), and Klondike Canyon generally showed no measurable movement. The City's geologist attributes the increase largely to erosion at the landslide's toe from wave action, caused by extreme southerly swells during an unusually active hurricane season in the southeast Pacific. The City says the complex is still moving about 30% slower than a year earlier, and the staff report puts the Portuguese Bend slide's slowdown since just before the deep wells were installed at 91%; by that report's figures, the slide had averaged 11.02 inches per week in July 2024, the peak month.

  As of the City's staff report for the Nov. 4 meeting, power had not been restored in the Portuguese Bend Community Association neighborhood, which has been without electricity since September 2024. SCE has said it needs a continued and sustained reduction in movement near its electrical infrastructure to less than 1 inch per week before it will consider re-energizing the Portuguese Bend area. In August the City Manager asked SCE's chief executive to meet in person to reconsider that threshold, and on Sept. 9 the City said staff were coordinating a meeting with SCE that month to discuss its re-energization plans. In an Oct. 13 letter, made public with the Nov. 4 staff report, SCE said movement in the Portuguese Bend area "continues to exceed the one inch/week safety threshold" and that it would keep its threshold; the letter does not say which measurements SCE used, and it predates the City's Oct. 28 figures. According to that staff report, the City and SCE's chief operating officer were scheduled to meet on Oct. 30; as of Nov. 5, 2026, neither the City's written updates nor SCE's pages had reported the outcome. Next check: the Nov. 17 SCE item and the City's Nov. 12 weekly report.

  Sources: City 2026 Community Updates Archive (July 9, July 29, Sept. 9 and Oct. 28, 2026 entries) · staff report for the Nov. 4, 2026 Council meeting (Regular Business Item 3; a large PDF), pp. 2, 11, 14–15, 25, 52–53, 58 and Attachment U · Sept. 15, 2026 Council staff report · City Manager weekly report No. 26-37 (Sept. 16, 2026) · City Manager weekly report No. 26-38 (Sept. 23, 2026) · No. 26-39 (Sept. 30, 2026) · No. 26-41 (Oct. 14, 2026) · No. 26-43 (Oct. 28, 2026) · No. 26-44 (Nov. 5, 2026) · RPVtv City Council Update, Nov. 4, 2026 (City video, posted Nov. 5) · Draft minutes, Oct. 6, 2026 Council meeting · City Manager weekly report No. 26-27 (July 8, 2026) · FEMA release R9-NR-26-36 (Sept. 29, 2026) · Official minutes, Aug. 4, 2026 Council meeting · City Manager weekly report No. 26-31 (Aug. 5, 2026) · City 2025 updates archive (Nov. 5, 2025) · Governor's proclamation terminating states of emergency (Sept. 21, 2026) · City Home Stabilization page (checked Nov. 5, 2026) · City Land Movement Updates and SCE RPV page (both checked Nov. 5, 2026).

• October 14, 2026

  City announces formal award of buyout grants

  The City announces that it "has been formally awarded over $54 million" in FEMA grants for Rounds 1 and 2 of its Voluntary Property Buyout Program: 22 homes and 5 homes, 27 pre-selected properties in all. The awards follow a federal regulatory review period. Because federal grants operate on a reimbursement basis, the City says it will buy homes a few at a time, expected to start "in the coming months," and that acquiring all 27 and demolishing the homes on them will likely take a few years; the land will be permanently deed-restricted as open space. A third round, the City's $19 million application for about eight more homes, remains waitlisted. In the City's RPVtv video update posted Nov. 5, 2026, City Manager Ara Mihranian says the Council approved nearly $56 million in federal grant funding on Nov. 4: more than $54 million for the voluntary buyout of 27 red- and yellow-tagged properties and $1.9 million for permanent power to the deep dewatering wells. No purchases had been reported as of Nov. 6, 2026. Next check: the City's buyout page, for the first purchases. The emergency and the management effort continue. The dated record is on the Updates page.

  Sources: City buyout program page (Oct. 14, 2026 update; checked Nov. 6, 2026) · staff report for the Nov. 4, 2026 Council meeting (a large PDF), p. 37 · City Manager weekly report No. 26-41 (Oct. 14, 2026), pp. 5–7 · City Manager weekly report No. 26-44 (Nov. 5, 2026), p. 5 · RPVtv City Council Update, Nov. 4, 2026 (City video, posted Nov. 5) · our update.

Landmarks of the Slide