The Economics of Protection against Sea-Level Rise: An Application to Coastal Properties in Connecticut

As a consequence of rising global sea levels, both the magnitude and frequency of coastal storms are expected to increase, which necessitates evaluating coastal flood adaptation measures. In this study, we conduct a benefit-cost analysis of coastal protection for 57 census blocks along the coast of Connecticut. The broad research question we address is whether benefits of coastal protection outweigh its costs. In cases where coastal armoring is desirable, our framework also allows us to determine the optimal timing of construction that maximizes expected net benefits. Our results suggest that in such cases coastal armoring can substantially alleviate the burden of total flood-related costs in the study area. The present value of cost savings due to coastal protection (relative to no protection) in the area over the next century amount to more than 26% with moderately high (physical, environmental, and amenity) costs and discount rate and range up to 41% under more conservative assumptions on the mod el parameters. Furthermore, the results we obtain imply that the optimal timing of protection may vary across different coastal regions.