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Water & Sanitation

Scientists Have Discovered Fresh Water Hidden Underneath the North Atlantic Ocean


Why Global Citizens Should Care
There is not enough water to cater to the needs of the world’s growing population. The United Nations’ Global Goals urge countries to more sustainably manage water supplies in order to avert crises and ensure the health and well-being of all. You can join us in taking action on related issues here.

Scientists have mapped out gigantic, underground freshwater reservoirs, just off the northeast coast of the United States, and their work could help solve world's water crisis.

Researchers from Columbia University and the Woods Hole Oceanographic Institution were surprised by the size of the giant aquifer of fresh water, which they determined on a 10-day expedition in 2015. Though these pockets of fresh water were assumed to be abundant within these continental shelves, their sizes and exact locations were previously intractable.

“We knew there was fresh water down there in isolated places, but we did not know the extent or geometry,” said lead author Chloe Gustafson, a Ph.D. candidate at Columbia University’s Lamont-Doherty Earth Observatory, in a press release

The researchers used electromagnetic sensors to map pools of fresh water beneath the ocean floor between New Jersey and Massachusetts, and published their findings earlier this month.

Because salt water conducts electromagnetic waves more easily than fresh water, researchers were able to distinguish one type of water from another and map out the extent of the once mysterious reservoirs. The study, the first of its kind, revealed a aquifer system beneath the ocean that spans at least 217 miles (350 kilometers) off the Atlantic coast and contains large quantities of low-salinity groundwater.

Geologists believe that these underground pools of water were created during the last Ice Age, when vast amounts of fresh meltwater from glaciers became trapped in rocky sediments under the ocean’s surface. First discovered by oil companies drilling for fossil fuels in the 1970s, these isolated freshwater pockets initially sparked curiosity among researchers, but little data was available at the time. 

Now, researchers believe that the low-salinity water found under the North Atlantic Ocean might help resolve the freshwater crisis the world is currently witnessing. 

“It could turn out to be an important resource in other parts of the world,” Gustafson said. “If found on the surface, it would create a lake covering some 15,000 square miles,” the report said.

Globally, 2.7 billion people face water scarcity at least one month of the year. About 2 billion people drink from water sources contaminated with feces that can cause diseases like cholera, typhoid fever, and other water-borne illnesses. According to the United Nations’ estimates, by 2025, half of the world’s population will be living in water-stressed areas.

Read More: Over Half the World Could Face Water Shortages by 2050

Researchers hint that the massive freshwater aquifer may extend way beyond the North Atlantic Ocean.

“The study suggests that such aquifers probably lie off many other coasts worldwide, and could provide desperately needed water for arid areas that are now in danger of running out,”  the report says.

"If we consider the potential northeast and southwest extensions beyond our profiles, there may be several times more groundwater underlying the northeast portion of the US Atlantic continental shelf, representing a freshwater resource that rivals the largest onshore aquifers."

The possibility of actually using the reservoirs as sources of drinking water remains far off. Before the water can be safely consumed, it would need to be desalinated and treated. Still, the existence of the giant aquifer might suggest the existence of similar groundwater systems in hotter and drier parts of the world like California, Australia, or the Middle East, that could eventually be in need of alternative freshwater sources.

“We probably don’t need to do that in this region,” Kerry Key, co-author of the report and geophysicist, said, referring to the American northeast.

“But if we can show there are large aquifers in other regions, that might potentially represent a resource.”