Estimating the loss‐reduction effects of disaster preparedness and mitigation: An empirical study of US coastal states

As extreme weather events like floods and storms continue to increase, it is crucial to examine the degree to which various disaster preparedness and mitigation investments can lower these risks. In this research, we empirically examine the effects of multiple federal disaster aid programs on reducing subsequent flood- and storm-related damages across US coastal states. Our analysis distinguishes aid programs and their funded projects targeting different emergency management functions, including preparedness, nonstructural and structural mitigation, emergency response and protective measures, and rehabilitation of public infrastructure. We construct panel data of more than 1800 US counties over the years 2000-2019 and estimate a fixed-effects model with time-varying county-level socioeconomic and demographic characteristics. We find that disaster aid generally helps mitigate property damages, although this loss-reduction effect varies by program. Among all aid programs, the Emergency Management Performance Grant results in the largest reduction of future flood damages. The Public Assistance grants supporting emergency work are also found to exert a strong effect on risk reduction. We also find that the impacts of disaster aid are higher in coastal counties. Our study is one of the first few examining the resilience implication of disaster aid in coastal counties, and our results underscore the importance of investing in capacity building, contingency planning, and consistency in maintenance.