Case Study: Planning, Mitigation
Pacifica State Beach San Pedro Creek Project
City of Pacifica, California:
The city of Pacifica had long battled chronic coastal flooding and beach erosion. For decades, the city had employed structural stabilization techniques to armor Pacifica State Beach and channelize San Pedro Creek.
Background and Approach
Despite these earlier stabilization activities, the City continued to face three main shoreline management issues: flooding of homes and businesses; erosion of Pacifica/Linda Mar State Beach; and maintaining habitat for the steelhead (Oncorhynchus mykiss) population in San Pedro Creek.
In 1982, a major flood damaged more than 300 homes. One home was eventually lost, and two homes and a restaurant remained threatened by storm surges and erosion. Therefore, the U.S. Army Corps of Engineers and the City's Flood Control Committee supported proposals to further harden and channelize the creek to reduce the risk of flooding.
At the same time, community members were also concerned about ongoing erosion at Pacifica/Linda Mar State Beach a popular surfing location. The surfing community, led by Pacifica's mayor, favored shoreline restoration and argued that the shoreline armoring was accelerating long-term erosion on the community's beach.
Further complicating the issue, San Pedro Creek supports a native population of steelhead. The California Coastal Conservancy and other partners therefore argued for restoration of the lower channel and creek mouth to improve habitat for steelhead and other species. In the early 1990's the City of Pacifica, the California Coastal Conservancy, and the Pacifica Land Trust decided to collaborate to work toward a hybrid solution, that would combine both "soft" or non-structural stabilization techniques and policy and planning techniques.
During the 1990's, the City of Pacifica partnered with the California Coastal Conservancy, the California Department of Fish and Game, the Army Corps of Engineers, and the State Water Resources Control Board to expand and enhance the tidally influenced wetlands at the creek mouth and restore more than 1900 feet of eroding creek banks. This restoration both enhanced steelhead habitat and achieved 100-year flood protection for the nearby community. The wetland project also cost the community significantly less than other proposed flood control measures because it required less physical construction.
To address the remaining flood threat to homes and businesses, the City purchased and removed the most vulnerable buildings. In 2002, the City partnered with the Pacifica Land Trust and the California Coastal Conservancy to purchase two homes and their surrounding acreage for $2.2 million. They demolished and removed the homes and excavated concrete, rubble, asphalt, reinforcing steel, and tires. They then delivered 4,000 cubic yards of sand to rebuild dunes and restore four acres of beach and the nearby estuary.
Challenges and Lessons Learned
Creative partnerships at local and state level helped leverage the public support needed to implement a project that cost millions of dollars and took a decade to complete. Support of local government leaders, particularly the mayor, helped finance an expensive and ongoing project. Finally, a planned retreat strategy was made more politically viable because project partners had the capital necessary to purchase threatened buildings outright. The project will protect the beach from future development, eliminate the need for seawalls to prevent flooding of existing homes and protect the mouth of San Pedro Creek and the Steelhead fishery.
Website accessed October, 2007