Social and Spatial Inequities in Exposure to Flood Risk in Miami, Florida

Although environmental justice (EJ) research in the United States has traditionally focused on technological hazards such as air pollution or hazardous waste, the adverse and unequal impacts of Hurricane Katrina have prompted researchers to examine the EJ implications of natural events such as hurricanes and floods. This paper contributes to this emerging literature on EJ and social vulnerability to natural hazards by analyzing racial/ethnic and socioeconomic inequities in the distribution of flood risk exposure in the Miami Metropolitan Statistical Area (MSA), Florida—one of the most hurricane-prone areas in the world and one of the most ethnically and socioeconomically diverse MSAs in the United States. Although previous studies have relied exclusively on the 100-year floodplain to assess the spatial extent of flood exposure, this study makes a systematic distinction between different types of flood zones on the basis of both the probability (100-year versus 500-year versus low/no risk) of flooding and location/nature (coastal versus inland) of the 100-year floodplain. The analysis integrates information from floodplain maps with census tract level sociodemographic data. The results demonstrate how the significance of various sociodemographic predictors of flood risk differs across relevant flood zone categories. Specifically, non-Hispanic Black and Hispanic residents are significantly overrepresented in inland flood zones and underrepresented in coastal flood zones characterized by significantly higher median income and housing values. These disparities have important implications for EJ research on flood hazards and related public policy in and beyond the Miami MSA.