When we started running out of oil on land, we went offshore to get more. It’s the same for key minerals such as zinc, copper, and phosphorus–these days, deep ocean mining is taking off in a big way.
Is mining the deep ocean for water what’s coming next?
It’s possible, because there’s a huge shortage of clean water in many places, and there’s plenty of good quality liquid in the ocean–and we’re not even talking about the salty water that fills it. A new paper in the journal Nature estimates there’s half a million cubic kilometers (120,000 cubic miles) of low-salt water underneath the seabed. And it’s not far from shore either.
The reserves were formed thousands of years ago when the sea level was much lower than it is now, and the world’s coastlines were further out. When it rained, water settled in aquifers in the rock and remained there when the oceans started rising. Researchers say it would be relatively easy to extract it, and it would cheaper and less-energy-intensive than desalinating actual ocean water.
“Knowing about these reserves is great news because this volume of water could sustain some regions for decades,” says Vincent Post of Flinders University in Australia, who led the study.
He adds: “Freshwater on our planet is increasingly under stress and strain so the discovery of significant new stores off the coast is very exciting. It means that more options can be considered to help reduce the impact of droughts and continental water shortages.”