Nearly 600 Million Gallons Pumped From Palos Verdes Landslide

RANCHO PALOS VERDES, CA — Nearly 600 million gallons of groundwater have been pumped from the sprawling landslide complex in Rancho Palos Verdes over the past two years, as city officials work to limit further movement and prepare the unstable hillside for another rainy season.

According to the city's Oct. 21 administrative report, approximately 585 million gallons of water, equivalent to 1,794 acre-feet, have been extracted through its deep dewatering well program since September 2024.

The wells are part of an extensive effort to stabilize the Greater Portuguese Bend-Ancient Altamira Landslide Complex, where groundwater has contributed to shifting terrain, damaging homes, roads and infrastructure. Removing water from deep underground is intended to reduce the pressure that drives the landslide, although the operation does not mean the ground has stopped moving.

Of the original 11 wells installed by the city, nine remained in service as of Oct. 21, with eight operational. The ninth had been redrilled and was awaiting a new pump and electrical activation, which officials expected to complete by the end of that week. The report did not confirm whether that work was subsequently completed.

Meanwhile, the city has finished its originally planned preparations for the 2026-27 rainy season, including securing canyon liners, clearing drains, replacing sandbags, filling ground fissures and carrying out erosion-control improvements.

The work began in July and was completed during the first week of October, according to the report. Additional drainage improvements along Palos Verdes Drive South, near the former Wayfarers Chapel and Klondike Canyon, have also been completed.

City officials said those improvements should reduce reliance on pumping operations and lower the risk of road closures during storms. With more rainfall potentially adding groundwater to the unstable hillside, city staff and geologists are evaluating whether further protective measures will be needed.

The pumping and drainage projects form part of Rancho Palos Verdes' continuing response to the landslide emergency, with officials monitoring conditions as work proceeds. Additional information about the landslide and ongoing remediation efforts is available through the city's land movement updates.

Related:

• Redondo Beach Approves Nearly $2M For Emergency Drain, Sewer Repairs
• Palos Verdes Weighs $6M Expansion Of Landslide Engineering Contract
• Rancho Palos Verdes Gets $1.9M To Reduce Landslide Pumping Costs