High urban flood risk and no shelter access disproportionately impacts vulnerable communities in the USA

Vulnerable communities are disproportionately placed in low-lying, flood-prone neighborhoods, with deficient infrastructure and limited access to shelter. Here we present a methodology to study the risk of urban floods in tandem with access to shelter to reduce the risk of flooding to communities and prevent a natural hazard from turning into a human disaster. We integrate access to national emergency shelters into a national risk index for riverine floods in eight U.S. cities at the block group level using clustering techniques. The results show shelters are more accessible for inner-city residents regardless of the risk level, and communities with high risk of flood and low access to shelter are disproportionately home to the underserved populations of Asians and the elderly. The outcomes delineate the disparity in equity related to urban floods and support plans and policy needs by identifying and prioritizing areas to improve emergency responses and resource allocations.