Climate change is making flooding more frequent and intense, and a new study in Nature Cities reveals that in Latin American countries, low-income neighborhoods bear the brunt of the impact.

Researchers from the Dornsife School of Public Health, with a team of investigators from Latin America, found that residents of neighborhoods with the lowest education levels were 4.3 times more likely to experience flooding than those in more highly educated areas.

The study analyzed nearly 20 years of flood data across 276 cities in eight Latin American countries. It found that 38 million people — 17% of the population — lived in neighborhoods that flooded at least once between 2000 and 2018. Moroever, 1 in 4 residents in the lowest-education neighborhoods faced flooding, compared to 1 in 20 in the highest-education neighborhoods.

The work, part of the Climate Change and Urban Health in Latin America (SALURBAL-Climate) Project led by Drexel’s Urban Health Collaborative, is the first of its kind to examine neighborhood-level social determinants of flood exposure in Latin America.

228,000,000

Researchers analyzed 45,000 neighborhoods in 276 cities that are home to 228 million people.

“The message is clear that policymakers must give careful attention to poorer neighborhoods that may be both at higher risk for flooding and have less infrastructure to be able to cope with the effects,” says Josiah Kephart, assistant professor in the Dornsife School of Public Health.

The findings highlight the urgent need to prioritize marginalized communities in climate adaptation policies, ensuring they are not left behind as extreme weather events increase.

Although the study was not designed to explain why these disparities were observed, the neighborhoods that suffered from flooding were likely the most devalued, with lower housing prices, and therefore available to low-income populations, says Nelson da Cruz Gouveia, SALURBAL-Climate co-investigator and professor at the University of São Paulo.

The researchers call for proactive mitigation efforts to help reduce flooding and its impact on disadvantaged neighborhoods.