Coastal Erosion Analysis

Erosion risk was studied by a team of scientists and engineers at Philip Williams & Associates, Ltd. (PWA). Information on the methods, assumptions, and limitations of this analysis can be found in Section 2.3.2 of Pacific Institute's study Impacts of Sea Level Rise on the California Coast.

The study area for the erosion analysis was constrained by data availability. The erosion analysis covered the 11 counties north of Santa Barbara County. Furthermore, data limitations limited the analysis to only 81% of the coast in these 11 counties (see table). The three counties with the least coverage include Humboldt County, Monterey, and Santa Barbara. Humboldt County included the Kings Range and the Lost Coast--public lands with no development. The Monterey County analysis was limited along the Big Sur coast where high levels of erosion currently impact the major transportation corridor of Highway 1 which can be expected to continue. In Santa Barbara, missing data along the region between Pt. Conception and Goleta and the ending of the erosion analysis south of Santa Barbara harbor explain the missing erosion analysis.

This information is being made available for informational purposes only. Users of this information agree by their use to hold blameless the State of California, and its respective officers, employees, agents, contractors, and subcontractors for any liability associated with its use in any form. This work shall not be used to assess actual coastal hazards, insurance requirements, or property values and specifically shall not be used in lieu of Flood Insurance Studies and Flood Insurance Rate Maps issued by the Federal Emergency Management Agency (FEMA).

County Miles sudied Miles of coastline Percent studied
Del Norte
Humboldt 72.9 123.3 59%
Marin 69.5 75.2 93%
Mendocino 145.5 151.4 96%
Monterey 94.4 132 71%
San Francisco 7.5 8.8 85%
San Luis Obispo 77 102.6 75%
San Mateo 57.8 59.6 97%
Santa Barbara 84.4 116.5 72%
Santa Cruz 46 46 100%
Sonoma 63 68.9 91%
Total 760.7 934.1 81%

Created by the Pacific Institute, 2009.