Efficient Flood Risk Mitigation and Intersectional Equity Implications: A Case Study in New Orleans

Abstract

AbstractGovernment agencies often require cost-benefit tests for environmental risk mitigation measures. These tests implicitly prioritize more valuable assets and may therefore produce inequitable outcomes. Previous studies propose directly prioritizing vulnerable groups or minimizing Gini coefficients, but these violate popular notions of procedural equity. We propose an alternative non-monetary risk measure which treats homes as equally valuable, improving distributional outcomes without violating procedural norms. As a case study, we compare optimal fixed-budget housing elevation strategies in New Orleans which respectively minimize flood risk measured as (i) economic damage, and (ii) the proportion of a structure’s replacement cost. The latter strategy allocates more resources to impoverished neighborhoods and reduces proportional damage to housing by an additional 11% at the expense of 2% of economic damage. Composite strategies provide more favorable tradeoffs (4% of proportional damage for 0.04% economic damage). This analysis demonstrates the value of non-monetary risk measures in pursuing equitable outcomes.