Undersea Freshwater Reserves Could Quench the World’s Thirst for Decades

By Breanna Draxler | December 6, 2013 3:07 pm

diversFreshwater is fast becoming a scarce resource as our global population swells. Some say World War III will be fought over access to it. But newfound reserves of freshwater under the sea may represent a vast source that has been previously overlooked.

Researchers announced this week that they’ve probed the extent of freshwater reserves under the sea off the coasts of South Africa, China, North America and Australia. Scientists have known about these pockets for a while but had no idea how many or how large they were. Now researchers estimate they contain about 120,000 cubic miles of water. Each cubic mile is equivalent to 1.1 trillion gallons, enough water to satisfy all of the United States’ present water usage for about 9 days. The lead researcher put it in perspective for Agence France Presse,

“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.”

Forgotten Freshwater

These pockets of freshwater formed during the Last Glacial Maximum, as described in The Raw Story,

The deposits were formed over hundreds of thousands of years in the past, when the sea level was much lower and areas now under the ocean were exposed to rainfall which was absorbed into the underlying water table. When the polar icecaps started melting about 20,000 years ago these coastlines disappeared under water, but their aquifers remain intact — protected by layers of clay and sediment.

Since it isn’t as salty as seawater, the reserves would be easier and cheaper to desalinate for consumption. The researchers say these freshwater reserves could sustain certain regions of the world for decades.

Water Hurdles

However these underground puddles aren’t filled with Evian. The water is brackish and will require a fair amount of filtering. In addition, some larger problems loom.

One, the water will be difficult to extract. As described in the Huffington Post,

Drilling for the trapped water would be an expensive endeavor, and engineers have only two options to tap it. They can build a platform out at sea and drill into the seabed, or drill from the mainland or islands close to the aquifers.

And two, these are non-renewable sources of water. Our existing aquifers eventually get replenished by rainwater, but these newfound reserves are completely cut off from the hydrologic cycle, according to the paper published in Nature. They won’t get refilled until the next Ice Age, when sea levels drop low enough to expose them at the surface. Use wisely, then.

Image credit: Krzysztof Odziomek/Shutterstock

CATEGORIZED UNDER: Environment, top posts
MORE ABOUT: freshwater, water
  • Saxdragon

    If it’s non-renewable, should we even bother trying to get to it?

    • JD

      Great point, however when it comes to making money corporate greed knows no boundaries. 😉

      • NameNotGiven

        Because pushing growth is only from corporations? Take a look at large central governments. They push headlong blind growth even more.

        • Buddy199

          For themselves and their power.

      • Glenn Jones

        Yes it does! One such boundary is profit. Industry knows of many resources that are uneconomic to extract so they remain unexploited. Commerce is driven by profit. Those businesses that forget usually suffer terminal consequences. Economics 101 – logic, but hardly science. Still every scientist should know this in order to avoid making sweeping statements

  • andrew

    yay we found a non renewable resourse… Let’s plunder it.

  • DL

    What difference does it make that it is non-renewable? It is doing no good sitting there, extracting it does no harm, why not extract as get some good use out of it?

  • http://blogs.discovermagazine.com Tat Yuen

    The water will be subjected to evaporation and thus it will become rain, and will add to the volume of surface water. But what will fill the volume of displaced water?

    • SixSixSix

      Water. Sea water.

      • blueshifter

        …thus solving the problem of rising sea levels! what could possibli go wrong?

        • SixSixSix

          Sounds fracking great to me.

  • mothman777

    How long before they nuke it with depleted uranium, like they did with the Libyan man made waterway that could have greened all Northern Africa for 100 years.

    • Rossamus

      Gaddafi’s ditch was useless. It never worked. They were hiding army junk down there.

      • mothman777

        Is that so? Do you reckon they dug it just for that purpose then? You reckon that must be the reason they bombed all the laid pipe and even the areas storing piping yet to be laid with misleadingly named ‘depleted’ uranium warheads, so that even they would be too contaminated to use, that is, the ones that were not in little pieces as a result.

  • Greg

    That last statement about not refilling until the next ice age seems wrong. There is an ocean of salt water above these aquifers now, how would future rain or ice bet different from an ocean. More probable outcome would seem to be an increasing brine level as “fresh” water is extracted.

    • LIORA

      Why go so far when we have plenty of rain water !!!!!!

  • Arthur W. Arre

    Either it’s fresh water trapped under the sea ,which is newsworthy,or it’s salty in which case it isn’t .Article says both.I can get this level of “reporting” in the Weekly World News and keep up with Batboy besides.Why bother subscribing to Discover too?

    • http://blogs.discovermagazine.com Breanna Draxler

      Hi, Arthur. Salinity is not an all or none type of characteristic. The water discussed here is freshwater and is far less salty than seawater. The fact that it is less “clean” than spring water is to be expected due to its age and location.

  • colindenronden

    But will it cause subsidence and even minor earthquakes? In Manila they extracted groundwater, and now the land is subsiding faster than sea levels are rising, risking great floods in times to come.

  • Anotherandrew

    And currently we pump freshwater into the ground to displace oil. Removing it from the hydraulic cycle and destroying it at the same time. Then using the byproduct to further destroy our environment.

    I’m sure we will use this resource with as much thought of humanity as we have in the past. Would WWIII be as much about water access or more about population reduction so we can use our dwindling resources as inefficiently as before but with fewer people.

    Feeling somewhat pessimistic this morning. Maybe after my shower things will look brighter.

  • Konrad Zebadiah

    maybe it’ll trigger an earthquake? I hate all this “well its just sitting there argument. The redwoods are just sitting there too and think of all the wood we’d get from them. lol fuking tards.

  • atzkoit

    You can’t know the harm that is done by extracting it until it happens. We need to use theintelligence we’re blessed with to get us out of the conundrum we face as a species that creates its own problems. Learning not to live in consequence and with some amount of reservation (not obsolescence at the expense of out environment and our future generations) would not kill us and may even hold the key to true sustainable innovations.
    Someone once said that the key to true creativity is limitation.

  • Sandy

    Of course its non-renewable, it’s also inexhaustible, it’s water. It can’t escape into space and as much is liberated in chemical reaction as is absorbed. Some of the water on the planet is “fresh” and some of it has dissolved components that make it unacceptable for human consumption without reprocessing. Fortunately, we have one of the best contaminated water recycling systems available. It’s called sunlight and then rainfall. If this water is extracted and used, it will be replaced with seawater but the ocean level won’t change because we will just use it and it will get recycled back again. The interesting question is how would global climate change? Water vapour (both clouds and humidity) is
    the highest component of Green House Gasses. If we increase evaporation by using sources of water that haven’t been available in the past, will we change climate and by how much. That’s the more interesting question.

  • mothman777

    How long before they nuke it with depleted uranium, like they did with the Libyan man made waterway that could have greened all Northern Africa for 100 years.

  • 王宇

    But will these water become some cherish materials?It’s hard to prove it to water.


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