Summary of Differences between the Three Regions 9
Responses to Shoreline Change 13
Challenges Quantifying Economic Effects of Shoreline change 18
Characteristics of Erosion and Accretion Responses in California 19
Summary of gaps in research 23
Northern California shoreline 26
Central California shoreline 29
Southern California shoreline 41
Appendix A 52
Appendix B 56
Erosion and accretion along California’s coast, particularly in the southern part of the state, has significant economic and social impacts for the state and nation. Any one or combination of factors including storm events, sea-level rise, man-made structures, and sediment deficits can cause erosion. Erosion leads to loss of sand and sediment from the coastal shoreline, affecting a variety of activities that are critical to society and the economy. Accretion, the accumulation of sand and sediment, can alter fish and shellfish habitat, effect wave breaks, and impede navigation by decreasing channel depth in harbors and bays.
To understand the economic and social implications of erosion and accretion along the California shoreline, it is important to consider the geographic context for these impacts. In California, three-quarters of the 1,100-mile coastline consists of high cliffs and bluffs, often fronted by sandy beaches (Hapke et al., 2006). If coastal features like beaches and bluffs were unused and uninhabited, erosion would have little economic or social consequence for the state. But California’s shorelines are a critical resource to the state’s economic and social wellbeing; residents and tourists flock to beaches for recreation (e.g. surfing, jogging, birding, swimming) and numerous businesses are dependent upon resources accessible from the shoreline (e.g. fishing, boating, mineral extraction, shipping).
Together, these recreational and commercial uses generate substantial revenues for local communities and the state--over $52 billion in 2008 alone (NOAA, 2011). Additionally, the coast is the most popular place to live and work; approximately 80 percent of Californians live within 30 miles of the coast (Griggs, 1999) and three of the ten most populous cities in America can be found along California’s central and southern shores (Los Angeles, San Jose, and San Diego).
While California has the largest ocean economy in the nation (Kildow, 2005), the combination of population, coastal processes, and economic activity tends to focus the discussion of economic and social impacts in the central and southern regions of the state. The ocean economies of all three regions (northern, central, and southern) rely heavily on tourism and marine transport, however, they exhibit pronounced differences in total employees, wages, and gross domestic product (GDP) within their respective ocean sectors.
Environmental variables, such as climate and water temperature, make Southern California a popular place to live, visit, and partake in beach recreation. These favorable conditions may contribute to this region’s ocean economy being more than ten times larger than the northern region ($3 billion versus $36 billion in 2008) (NOAA ENOW, 20111). It should come as no surprise, therefore, that the social and economic impacts of erosion and accretion are better documented for the central and southern shorelines of the state, which host year-round beach recreation, three of the top ten largest U.S. ports, and three of the top ten largest U.S. cities. Although studies have shown that the northern region is experiencing the highest rates of erosion in the state (Hapke et al., 2009), there are few documented social and economic impacts due to sparser development and less favorable coastal recreation conditions. The dearth of documentation seems to indicate that there are fewer social and economic impacts of erosion and accretion along the northern shoreline.
This report examined the social and economic implications of erosion and accretion through a literature review, data search, and discussions with the California Coastal Sediment Management Work Group, an affiliation of federal, state and local coastal managers as well as non-profit organizations engaged in shoreline management issues in California. The scope of the research on costs was limited to the cost of beach renourishment reported by state and federal agencies, however, where information was found on other costs, it was included in this report.
Based on the information gathered, several distinctive attributes emerged to characterize the economic and social impacts of shoreline change in California and the state’s response to these changes. These include:
Beneficial use of dredged material: Re-using dredge material for beach renourishment and wetland restoration appears to be a cost-effective strategy for a state such as California, which faces continual sediment accretion in its many ports and harbors and sediment deficits in other areas.
Aesthetics: The aesthetics of shoreline stabilization methods are a major issue of social importance in California and are considered by state agencies in the application of the state’s coastal policies.
Recreation: Beaches host a variety of recreational uses that can be affected by a changing shoreline. Erosion usually narrows beaches, which can limit access, the number of users, and the overall quality of the beach experience. Beach renourishment and shoreline armoring are common responses to erosion, and user groups are very engaged in the decision-making process to determine the most appropriate response. The surfing community in particular is actively involved in shoreline management issues, especially in the southern part of the state.