Economic Analysis of Impacts of Sea Level Rise and Adaptation Strategies in Transportation

Although the causes of the sea level rise (SLR) are hotly debated, almost no disagreement exists that sea levels will continue to rise. The SLR is likely to have significant impacts on coastal transportation infrastructure. Adaptations in response to the SLR are in urgent need. Facing various adaptation strategies, decision makers need information on the impacts of different SLR scenarios as well as the economic trade-offs of various adaptation strategies. This research attempts to quantify the economic impacts of the SLR as well as the costs and benefits of adaptation strategies by using cost–benefit analysis at the local level. Hillsborough County, Florida, is used as a case study, and two projected scenarios for the SLR are applied to it. Light detection and ranging data, parcel land use data, and transportation network data for the county are employed to estimate the impacts of the two scenarios. Three adaptation strategies are suggested to the proposed SLR scenarios. Then cost–benefit analysis is conducted for each strategy under the two scenarios that consider the impacts of both direct inundation costs and indirect travel time costs. On the basis of the present values of the net benefits in the proposed strategies, managed retreat with critical infrastructure protection is the best adaptation strategy for the SLR in the long run and the length of shoreline protection is the most sensitive to the net benefits.