Coastal Regions of Brazil Face High Risks of Floods and Landslides

Recent events in Rio Grande do Sul underscore the susceptibility of Brazil’s coastal areas to floods and landslides, discussed by experts in a Rio de Janeiro debate.

Osvaldo Rezende, a water resources expert and professor at the Federal University of Rio de Janeiro (UFRJ), emphasized the flood risks.

Brazil’s coastal areas, from Macapá in the north to Pelotas in the south, are highly susceptible.

“Flat regions hinder water flow through river basins, causing quick water discharge. The nearby sea exacerbates drainage issues during high tide,” Rezende explained.

Marcelo Seluchi, general coordinator at the National Center for Monitoring and Early Warning of Natural Disasters (Cemaden), noted the landslide risks.

High population density, steep topography, and heavy rainfall contribute to these dangers.

Seluchi noted that the Serra do Mar region, covering Espírito Santo to São Paulo, is high-risk for frequent summer landslides.

Urbanization worsens flood risks, according to Rezende. More urban areas mean fewer forests to retain water.

Less permeable soil causes faster water runoff, increasing danger. “Urbanization makes flooding more likely and severe,” he added.

Coastal Regions of Brazil Face High Risks of Floods and Landslides

Seluchi highlighted widespread flooding in the Amazon regions. Flat terrain causes floods to last for months.

He mentioned that while large river basins like São Francisco and Paraná take days to flood, smaller basins like Petrópolis’ Quitandinha can overflow in fifteen minutes during heavy rain.

Central-western regions and parts of the north are less prone to landslides. These areas are sparsely populated and flat. Therefore, landslide risks remain lower there.