Samuel Goldberb, USC pprofessor documents the history in his paper: "Falling into the Pacific: California Landslides and Landuse Controls."

 

On March 12, 1928 Santa Clara Valley

 

The St. Francis Dam failed in Los Angeles County, forcing a destructive wave of water over fifty miles through the Santa Clara Valley and into the Pacific Ocean; roughly 500 people lost their lives and damage exceeded $600 million (in year 2000 dollars).

 

Winter to Summer, 1956-57, Palos Verdes

 

The Portuguese Bend landslide in Palos Verdes, started in 1956 and lasted into the summer of 1957. It was the continuation of landslides occurring over thousands of years in the Palos Verdes region.56 While humans may not have been the proximate cause of the landslide, the development in Palos Verdes contributed to the $14 million in damage (particularly since many of the single family homes had landslide-aggravating septic tanks).

 

From 1958 to 1971, landslides in Pacific Palisades cost over $29 million.

 

From 1977 to 1980 Los Angeles cost over $15 million in landslide damage occurred in Monterey Park, located in

Los Angeles County.

 

In 1980 Orange County

 

 In Bluebird Canyon, located in Orange County, a landslide following heavy

rains in 1978 damaged sixty houses, at a cost of over $52 million.

 

1981 Big Rick, LA County

 

year later, a landslide in Big Rock, Los Angeles County, damaged Highway 1 and cost over $1 billion.67

 

In 1983, landslides in Orange County’s San Clemente and Big Rock Mesa cost over $700 million in

damage and litigation fees.

 

 

This trend, of course, continued into the last decade of the twentieth century.

 

The 1994 Northridge earthquake, with a magnitude of 6.7, caused more than 11,000 landslides in an area of 10,000 square kilometers. Dozens of homes were destroyed, and roads and oil-field infrastructure were damaged. The landslide activity also released a spore that caused Coccidioidomycosis (otherwise known as “valley fever”), leading to several deaths. The following

 

1995 Los Angeles Ventura Counties

A year of above-average rainfall caused landslides in Los Angeles and Ventura counties, including the La Conchita landslide, in

which twelve homes were severely damaged or destroyed.