Can California coastal managers plan for sea-level rise in a cost-effective way?

Abstract

This paper examines five representative sites on the California coast to illustrate a cost-effective methodology using tools and data that local decision makers can apply to analyse the economics of sea level rise (SLR) adaptation. We estimate the costs/benefits of selected responses (e.g. no action, nourishment, seawalls) to future flooding and erosion risks exacerbated by SLR. We estimate the economic value of changes to public/private property, recreational and habitat value, and beach related spending/tax revenues. Our findings indicate that the costs of SLR are significant but uneven across communities, and there is no single best strategy for adaptation. For example, Los Angeles's Venice Beach could lose $450 million in tourism revenue by 2100 with a 1.4 m SLR scenario while San Francisco's Ocean Beach would lose $80 million, but the impacts to structures could total nearly $560 million at Ocean Beach compared to $50 million at Venice Beach.

Keywords:

• economics
• sea level rise
• adaptation
• benefit/cost

Acknowledgements

The production of this study would not have been possible without the generous input of many individuals. Our thanks go to all those who provided technical guidance, data, and timely comments that contributed to this study. We would especially like to thank the California Department of Boating and Waterways (DBW) and Kim Sterrett, former Manager of the Department's Public Beach Restoration Programme, for providing funding that made this study possible. We would also like to acknowledge the Office of Research and Sponsored Programmes at San Francisco State University for serving as the funding administrator for this study.

Notes

1. A berm is a horizontal build-up of sediment on the back of the beach that results from wave action or human action (e.g. tractor) (CIRIA 1996).

2. The foreshore is the section of beach that is wet under normal tide and wave conditions, extending to the mean high water line (Mangor 2001).

3. Depth of closure for a given or characteristic time interval is the most landward depth seaward of which there is no significant change in bottom elevation and no significant net sediment transport between the nearshore and the offshore (Kraus, Larson, and Wise 1998).

4. Wetlands and beaches have a number of similar ecological functions, e.g. see Center for Coastal Resources Management (2009).