Measuring Disparity in Flood Risk and Freeboard Benefits for Different Income Groups

Flooding is the second-most deadly natural disaster in the US, affecting a large population. However, the lower-income population often fails to undertake necessary measures against flood risks due to their economic incapacity and limited accessibility to information. Using at least 1 foot freeboard to elevate the first-floor level of a building above the base flood elevation is encouraged as a precautionary measure against flooding by National Flood Insurance Program without considering its implications at the micro-level. The generalized strategy prevents an optimal level of freeboard implementation, affecting the required initial investment and associated economic liabilities. This study proposes a new framework for analyzing the risks to benefits of using an optimal level of freeboard at the micro-level of the population and identifying disparity among different income levels. The framework helps identify factors that affect the ability to adapt to the new policy on freeboard and develops a method to measure the vulnerability of different communities empirically. One case study was conducted on Jefferson parish to elucidate the methodology. The research outcomes showed that lower-income households entail higher economic risks in adapting to the new freeboard policy; however, the benefits are also higher for lower-income groups than for higher-income groups. The study contributes to the existing body of knowledge by providing a prioritization framework that can help to identify and rank (1) the most vulnerable communities that face economic and other liabilities toward freeboard implementation and (2) the vulnerable areas that require further development for improving long-term resiliency.