Saltwater invasion: Driven by rising seas, the threats to drinking water, crops from saltwater are growing in Maryland and elsewhere in the U.S.

On Louisiana’s Gulf coast, hit by a record five hurricanes or tropical storms this year, Native American tribes are some of North America’s early climate refugees as seas claim their shoreline and salinity damages the land that remains.

Four Louisiana tribes requested United Nations assistance this year to force action by the U.S. government. They wrote in a formal complaint citing “climate-forced displacement” that saltwater has poisoned their land, their crops and their medicinal plants.


“That strips us of not only being able to generate an income to provide for ourselves, it also strips us of our ability to feed ourselves healthy,” Shirell Parfait-Dardar, chief of the Grand Caillou/Dulac Band of Biloxi-Chitimacha-Choctaw, said in an interview.

The tribes’ plight offers an extreme example of a lesser-known impact in the climate crisis: saltwater intrusion.


The landward movement of seawater threatens drinking water supplies, coastal farming and coastal ecosystems.

The cascading consequences of saltwater intrusion were starkly revealed in interviews with more than 100 researchers, planners and coastal residents, along with soil testing and analyses of well-sample data conducted by the Howard Center for Investigative Journalism.

New scientific research shows measurable and sometimes startling change, much of it from saltwater’s unseen advance beneath the surface. The threat is widespread; roughly 40% of Americans live in coastal counties, according to the National Oceanic and Atmospheric Administration.

Rising seas, more frequent storms, higher tides, drought and the pressure of pumping for drinking water combine to accelerate the salt invasion. Researchers say that as effects of the changing climate worsen, challenges for landowners, local planners and people concerned about sensitive coastal lands will grow.

“It’s not something that we need to wait until 2050 or 2100 for. It’s not something happening only to polar bears. It’s happening right now,” said Marcelo Ardon, a North Carolina State University ecologist and biogeochemistry who is documenting changes in North Carolina’s coastline. His view of the impact of saltwater intrusion is widely held in scientific circles.

Read the full story from the Howard Center for Investigative Journalism here.