Australian researchers said this week in the journal Nature that they believe vast amounts of freshwater lie trapped beneath ocean floors off coasts around the world, with New Jersey boasting one of the biggest reserves.

The scientists believe the reserves could be tapped in the future if freshwater diminishes as expected.

New Jersey already has a huge freshwater reserve with the Cohansey Aquifer, 17 trillion gallons of water under the Pinelands National Reserve that flow to the coastal plain and the Atlantic Ocean. Together, the two sources – inland and off the coast - could mean future generations seeking depleted water reserves could look to the Garden State.

The new study's lead author, Vincent Post, of Australia's Flinders University, said that an estimated 500,000 cubic kilometres (120,000 cubic miles) of low-salinity water had been found buried beneath the seabed on continental shelves off Australia, China, South America and North America – with New Jersey being an often cited example.

"The volume of this water resource is a hundred times greater than the amount we've extracted from the Earth's sub-surface in the past century since 1900," Post told Agence France Presse of the study.

He believes the reserves could sustain future generations.

"Freshwater on our planet is increasingly under stress and strain so the discovery of significant new stores off the coast is very exciting," Post told AFP. "It means that more options can be considered to help reduce the impact of droughts and continental water shortages."

More than 40 percent of the world's population already lives in conditions of water scarcity. By 2030, UN Water estimates that 47 percent of people will exist under high water stress. Tapping the water trapped under the ocean floor could provide freshwater for millions in future generations.

"The best-documented example of an offshore palaeo-groundwater body is the vast occurrence of low-salinity water extending below the continental shelf of New Jersey," the study's authors wrote.

They said recent borings and "high-resolution samplings" helped them reach their conclusions.

However, the authors note that accessing the water could bring ethical and ecological difficulties. The most promising methods for extracting the water were developed for petroleum exploration. Not only that, but the water might need to undergo some desalinization through reverse osmosis.

Contact Frank Kummer at 215-854-2329 or bmccrone@philly.com. Follow @frankkummer on Twitter.
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