By the end of this century, about 5,500 hazardous sites along US coasts could face regular flooding as sea levels rise because of climate change. A national study finds that more than half of those facilities may already be at risk as soon as 2050, turning future storms into potential toxic events rather than just high water.
These sites store or handle sewage, trash, oil, gas, and other materials, and many sit next to neighborhoods that already live with heavy pollution. The research, led by Lara J. Cushing at the University of California, Los Angeles and funded by the Environmental Protection Agency, concludes that low-income communities and communities of color are more likely to live close to facilities projected to flood.
Thousands of coastal facilities already on a ticking clock
To map the danger, Cushing’s team examined more than 47,600 coastal facilities, then combined their locations with sea level projections for 2050 and 2100. They focused on floods with about a one in one hundred chance of happening in any given year, a standard often used for insurance and building rules.
Under a high-pollution path, the study projects that 5,500 sites could face that level of flooding by 2100 and nearly 3,800 as soon as mid century. About 44 percent of the at-risk facilities are fossil fuel ports or terminals, with 30 percent power plants, 24 percent refineries, and 22 percent sewage treatment plants, largely in seven states including Louisiana, Florida, New Jersey, Texas, California, New York, and Massachusetts.
How rising seas can turn industrial sites into toxic floods
Sea level rise might sound slow, but it changes the starting point for every storm and high tide. As oceans warm and expand and some stretches of coastline sink, water can reach farther inland, overtopping defenses that once felt solid and pooling in low-lying industrial zones.
So what happens when floodwater moves through facilities that store fuel, chemicals, or waste? It can pick up those substances and carry them into nearby streets and homes. Public health experts such as Sacoby Wilson at the University of Maryland warn that people near sewage plants or large animal farms could encounter bacteria such as E. coli, while those near refineries face metals and chemicals tied to stomach illness, rashes, breathing trouble, and in the long run higher risks of organ damage or cancer.
Who lives closest to the danger?
The researchers then asked who lives within about two thirds of a mile of facilities that are expected to flood and compared those neighborhoods with other coastal areas that do not have an at-risk site. They found higher shares of renters, households in poverty, seniors, people who identify as Hispanic, and residents without cars near the hazardous sites.
That pattern echoes broader research on environmental injustice and earlier mapping of toxic flood risks in coastal California.Derek Van Berkel at the University of Michigan, who was not involved in the new study, said the most “alarming” part is the feedback loop as repeated floods spread contamination and make it harder for residents to recover before the next disaster.
Limits of the analysis and what could still change
Like any model, the analysis has blind spots. It leaves out some risky infrastructure such as oil and gas pipelines and does not estimate how future storms will change flooding, so the real-world threat could be higher.
The future is not fixed, and the authors say their flood model is best used as a screening tool rather than a precise forecast. Under a lower-pollution path, the study estimates that over 300 sites could avoid serious flood danger by 2100, and Thomas Chandler at Columbia University’s National Center for Disaster Preparedness calls this “a really important study” for planners trying to prevent disasters where damaged facilities spread toxins into floodwater. Cushing said “we do have time to respond and try to mitigate the risks and also increase resilience,” but that will only happen if officials, companies, and residents start planning before the next big flood arrives.
The study was published in “Nature Communications.”
