Risk communication in flood-prone communities: memories, informal practices and public action in Brazil

This study investigates how communities in flood-prone areas of Brazil, particularly in São Paulo and Rio Branco, engage in informal communication practices to manage flood risks. It critiques the disconnect between formal top-down risk communication led by authorities and bottom-up, community-driven strategies. The researchers propose a “public action” framework that bridges this gap, aiming to integrate community knowledge, experiences, and organization into formal disaster risk management.

The findings highlight that while formal flood communication is often limited or absent, communities actively use word-of-mouth warnings, shared flood memories, visual markers, and local gatherings to respond to and prepare for floods. These informal networks not only support immediate response efforts but also foster resilience and local ownership. The study concludes that valuing these grassroots practices and integrating them with institutional responses can lead to more effective and inclusive flood risk communication strategies.