Flood Damage Avoided by Potential Spending on Property-Level Adaptations: Working Paper 2024-03
Working Paper
This working paper provides estimates of the flood damage avoided from property buyouts and elevations and analyzes how the effects of adaptation spending could vary across regions, by area income, and for different subsets of projects.
This working paper provides an estimate of the potential damage avoided from spending by governments and homeowners on property-level flood risk adaptations, primarily buyouts and elevations. The literature on that topic offers some estimates, but they are difficult to compare and apply across contexts because they analyze different adaptation measures, cover different geographic scopes, and use different modeling approaches. To provide a set of internally consistent estimates, therefore, we develop a nationwide framework using inland and coastal residential properties that contain 1 to 4 housing units. We find that there are about 1.3 million projects (each of which adapts a single property) for which the expected avoided damage exceeds project costs. If those projects were all completed, they would cost a total of $193 billion and prevent $519 billion of expected damage over 30 years; each dollar spent would avoid $2.69 of expected damage, on average. Some projects would avoid more damage than others. Of the 1.3 million projects, roughly 138,000 would result in expected avoided damage that is over six times the cost of the project. We characterize how outcomes vary depending on area income and geography. Finally, we simulate outcomes for different large sets of projects that could be used to inform future program design.
