High on the Hill and Down by the River: The Relationship between Wealth and Flood Risk in the United States, Past and Present

Abstract

This work analyzes the relationship between flood risk and wealth in the United States and investigates the mental maps that inform the debate over the National Flood Insurance Program (NFIP). Through historical analysis, it first explores the mental maps employed in NFIP policy debates from the 1960s forward. The common mental maps of the relationship between wealth and flood risk are tested through a geographic analysis using decadal US Census data between 1970 and 2010 and NFIP flood maps. The study’s primary conclusion is that the mental maps that shape the national conversation about federal flood insurance do not capture the actual distribution of risk. The majority of counties in the high flood risk areas have had a low-median income in every census decade between 1970 and 2010. The majority of the ocean-adjacent counties at high risk of flooding have moderate-income levels today. Two extensive, low-income inland areas at high risk of riverine flooding have existed since the creation of the NFIP program but are overlooked in debates over program beneficiaries.