Huge reserves of freshwater lie beneath the ocean floor


December 11, 2013

Scientists have found huge freshwater reserves under the world's oceans (Photo: Shutterstock)

Scientists have found huge freshwater reserves under the world's oceans (Photo: Shutterstock)

Scientists in Australia have reported the discovery of huge freshwater reserves preserved in aquifers under the world's oceans. The water has remained shielded from seawater thanks to the accumulation of a protective layer of sediment and clay. And it’s not a local phenomenon. Such reserves are to be found under continental shelves off Australia, China, North America and South Africa.

The discovery was made by researchers at the National Centre for Groundwater Research and Training (NCGRT) and the School of the Environment at Flinders University. The scientists estimate there is around half a million cubic kilometers of what they describe as “low salinity” water, which means it could be processed into fresh, potable water economically.

The reserves formed when ocean levels were lower and rainwater made its way into the ground in land areas that were not covered until the ice caps melted 20,000 years ago, causing sea levels to rise.

"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," says study lead author Dr. Vincent Post. "Our research shows that fresh and brackish aquifers below the seabed are actually quite a common phenomenon."

To access these non-renewable water reserves, it would be necessary to drill into the seabed from man-made, offshore platforms or from the mainland or nearby islands. Despite the high costs involved, the water would require less energy to desalinate than it does to desalinate sea water, although a careful assessment of the economics, sustainability and environmental impact of the exploration of such water reserves would be necessary.

Post added that humanity needs to be careful not to contaminate these aquifers while drilling for oil or disposing of carbon dioxide as suggested in some carbon capture and storage proposals.

Water scarcity is set to be one of the biggest environmental challenges of the 21st century, with global warming, deforestation, overpopulation, industrial demand, irrigation and several other factors taking a huge toll on the planet’s water reserves. According to UN-Water, in 2011 some 768 million people lacked access to suitable sources of drinking water. Seawater desalination plants are becoming a more widely-used source of drinkable water, but the process is generally costly and extremely energy-intensive.

The team's research is described in a paper published in the December 5th issue of Nature.

Source: Flinders University

About the Author
Antonio Pasolini Brazilian-Italian Antonio Pasolini graduated in journalism in Brazil before heading out to London for an MA in film and television studies. He fell in love with the city and spent 13 years there as a film reviewer before settling back in Brazil. Antonio's passion for green issues - and the outdoors - eventually got the best of him and since 2007 he's been writing about alternative energy, sustainability and new technology. All articles by Antonio Pasolini

Oh great, now we can exploit more non-renewable resources until we suddenly discover what terrible damage we have done. Then we'll try to convince people to go sparingly on the water and they'll claim hoax and complain that economic activity will suffer etc etc...

While this find is interesting I am obviously shocked that the first thought is to suck all the water out and use it. Shouldn't we be stopping the awful wastage of fresh water we do today?


Wonderful! Another one-time resource we can squander and postpone the actual dealing with the issue (aka not wasting resources like a bunch of hogs) to our children and grandchildren.

We humans are geniuses.


Hmm,. now we just need to find another similar reserve of oil for the next 100 years and we're set,... :b


I suggest that we capture the water from the burning of hydrocarbon fuel.


Are people that silly? Other than what bleeds off into space is reclaimed by the planet. Once you consume water, it doesn't disappear....The Oceans are a renewable source of water. Do we have to work to use it again via desalination? sure. but then if we want to use wood, another renewable resource, we have to grow the trees, cut them down, process them, etc...Our water is not just disappearing people, not like your thinking anyway. On a similar note oil is being recycled into carbon and other products. Its just going to take longer to recycle them that one might some aluminum cans or such things. There is no black hole where our resources are falling into once they are used.


It may not be that simple to suck that water out. On dry-land aquifers the level merely drops as air permeated down to where the water was. What replaces removed water when the aquifer is under the ocean? It seems like a recipe for its immediate contamination.

Think, then think again before doing it.


Why not pump down carbon dioxide, then we could have our own soda fountain? As far as desalination plants go, why can't they be operated using solar energy, either directly by evaporating water with solar heat, or using solar panels to generate electricity and evaporate the water that way? That way they don't cost much to operate.

David Clarke

it would be better to switch all our water consumption to sea water that has been desalinated. We should also try use the sea in production of hydrogen.

We should ban the use of fresh water. Sure it takes energy to desalinate water, but the sea creates wave energy, and wind energy, and we have sun energy, lets harvest that energy and use the sea as a renewable resource.

Once we start using the sea we will never have to issue hose pipe bans or go thirsty again, and also, it would be nice to see the maths to figure out how much we could use and would it have an impact on sea levels.


Using water out of a aquifer at a sustained rate faster than it is replenished is fairly stupid but using it as a reservoir to get through a drought makes sense.

For desalinization it should be noted that there is very little difference in the design of the boiler in a steam cycle power plant and a steam cycle desalinator.

As for what to do with the brine study Israel's dead sea industry.


Is this worldwide?? wow if so.

Stephen Russell

I thought it was obvious, it said rainwater like rain that runs off the continent through freshwater rivers into the ocean. Like the floods that wipeout half of Queensland every year that we ignore and let it go to the ocean, you know that desalination rainwater, that we spend a fortune trying to get.

Why not put a huge pipe under ground and collect that water for later usage like in dry periods, no Australians don’t want that. We are a nation of cures not prevention, you know, the best cure for a hangover is to moderate your drinking the night before not spending the next few days desalination our body.


With the Exclusive Economic Zone of Mauritius amounting to 2.5 million sq. kms, we should be able to tap in on that. Certainly much cleaner than pumping out polluting petrol!

Marcel Noë

Once the idea is out, it is always the wrong heads with $$$ eyes who rush in. They can care or less contaminating the last resort of fresh water. Not for money but Lake Vostok, anyone?

What happens to the sea level by sucking out such huge aquifers?

What do the great depth earthquakes do to the earth?

What happens when a drilling accident happens at or below the ocean floor, merging the huge aquifer and the ocean?

Quote: 'The water has remained shielded from seawater thanks to the accumulation of a protective layer of sediment and clay.'

It's already public knowledge, therefore it is too late. There is no medicine to cure human folly.


I think it funny that people all of a sudden start on the "precious resource", "squandering" slick. Man is innovative and time and time again has shown that once it makes economic sense to find an alternative solution to a problem, that problem gets resolved.

The "problem" with clean water is that we keep trying to use sources of water that are naturally clean. The tech is very close at hand for very cheap energy (fusion, renewables) and/or desalination technology. Couple that with better industrial size filtering and we now have oceans of water.

Water and energy shortages are really a short term problem (100 years?).

Rann Xeroxx

Tapping and ruining this supply does not sound like a good idea especially when in many places so much could yet be done with conservation and recycling. This was impressed on me while camping in a small trailer in the wild. A good shower can be had with a flexible shower line and 1 1/2 gallons of water. All water faucets should have some sort of auto shutoffs. Unbelievably, a 30 gallon water tank could hold a very generous week's supply of water for two people. I also remember a farmhouse that in the 1930s had two water systems. One held rainwater in a cistern for washing clothes and taking baths while a second well water system was used for cooking and drinking. We need to make a few changes in our lifestyle before resources become limited. The sooner we start, the less difficult it will be.


Water is a local resource we use so much of it that it is not economical to transport it across the world. So no mater how much of a drought Australia is going through forcing people in north america to live like savages is not going to help.

This also goes for regions in North America. Conserving water in Detroit is not going to help out with water shortages in Atlanta or Las Vegas.

Conversely if Australia start using this water it will not mean there is less water in Africa or North America to use. BTW the article mentioned that there is 500,000 Cubic Kilometers of water available.That is a lot of water. I don't think that a lot of these conservation types realize how much water that is That is a lot of water. How much water you ask? Try to visualize the entire continent to of Australia covered to a depth of 213 feet or for you metric types 65 meters. Pump it out and enjoy!


Did you know that the Bible records that there were fountains of the great deep that broke open as a contributor to a worldwide flood. Looks like there are still some left or perhaps they filled up again and have some as yet unidentified process that supplies or makes freshwater... Very interesting.

John Kline Kurtz
Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles