Stevenson Ranch

The Project.

The mid 90’s was the beginning of a boom in the growth of northern Los Angeles County. Stevenson Ranch started to take shape, resulting in more than 1,000 homes with retail, schools and other necessities of a whole community.


Lennar Homes


Stevenson Ranch, CA


  • Geotechnical
  • Geotechnical Testing

Project Fact:

Starting with a blank landscape of hills with the goal of a complete community, this project required extensive geologic investigations, and review by county and state agencies.

The Leighton Solution.

For more than a decade, Leighton provided geotechnical design, observation, and testing services within five tracts.

Located at the edge of the Santa Susanna Mountains the rolling hills required extensive earthwork for lot grading. In the end, 14 million yards of earthwork were moved.

The need for all infrastructure meant multiple agencies were involved, including County of Los Angeles Materials and Testing Division, State of California, Department of Water Resources, Division of Safety of Dams, Division of the State Architect, and the State of California Department of Conservation, Division of Oil, Gas & Geothermal Resources, and California Department of Transportation.

Technically, the 4,000 acres required definition of earth units, stability analyses of cut, fill and natural slopes, fault trenching for an Alquist-Priolo-style setback zone, stabilization fills and buttresses, and debris walls.