What shapes flood risk perceptions? Comparing public perceptions with FEMA flood hazard maps in the U.S.

Flooding remains one of the most damaging natural hazards, underscoring the need for a better understanding of public perceptions of flood risk to support preparedness and mitigation. This study compares risk perceptions from a national online survey of 918 respondents with FEMA flood maps. We define the risk perception gap as the difference between respondents' perceived flood risk and FEMA’s flood zone classifications, and we examine its drivers. Multinomial logistic regression was used to assess how socioeconomic characteristics, spatial context, and latent variables from Protection Motivation Theory (PMT) influence whether individuals perceive their flood risk as higher, lower, accurate, or express uncertainty about it. Many residents living in FEMA-designated floodplains perceive their flood risk as lower. The results revealed that higher perceived self-efficacy was associated with either elevated perceived flood risk or increased uncertainty. Greater perceived susceptibility was correlated with less uncertainty. People who live near water bodies perceive flood risk differently from what FEMA maps indicate, reflecting polarized perceptions of flood risk. A lack of awareness about elevated terrain (necessary for avoiding rising flood waters) tends to downplay their flood risk. Older individuals exhibited less uncertainty about their property’s flood risk. These findings highlight the need for targeted, place-based flood-risk communication strategies that address socio-cognitive and geographical factors. These strategies may help to reduce perception gaps, improve community preparedness and risk literacy, and strengthen resilience to flooding. The potential underestimation of flood risk in FEMA flood maps highlights the need for improved map accuracy and localized risk assessments. • Many residents in FEMA flood zones have lower perceived flood risk or are uncertain about their flood risk. • 57% of respondents in high-risk zones downplay their flood risk in FEMA-designated flood zones. • Socioeconomic status, spatial context, and psychological variables shape flood risk perceptions. • Place-based, socio-cognitive strategies can reduce perception gaps and improve preparedness. • Potential underestimation in FEMA maps calls for improved accuracy and localized risk assessments.