Flood risk perception and communication in informal settlements: evidence from Brazilian cities

This study evaluates flood risk perception and communication in five informal settlements in Brazil, three in Curitiba and two in Recife, characterized by recurrent flooding and socio-environmental vulnerability. A structured questionnaire was applied to 1,405 residents, and data were analysed using non-parametric tests, correlation analysis, and linear regression models. Indicators were normalized to a 0–1 scale, where higher values indicate greater perception or communication. Results show moderate levels of risk perception (0.48) and communication (0.43), with significant differences across communities (p < 0.001). Risk perception increased with age (β = 0.011, p < 0.001) and proximity to rivers (β = −0.022, p < 0.001), while households with vulnerable groups showed lower coping capacity (β = −0.017, p = 0.001). Despite high trust in authorities (0.65), preparedness remained low (0.27). Findings highlight persistent communication gaps and the need for community-based, context-sensitive risk communication strategies.