Vast freshwater reserves discovered under the ocean floor

Vast  freshwater reserves have been discovered under the ocean floor which scientists  believe could sustain future generations.

Australian researchers claim to have found  500,000 cubic kilometres (120,000 cubic  miles) of freshwater buried beneath the seabed on continental shelves off  Australia, China, North America and South Africa.

The discovery comes as United Nations estimates suggest water use has been growing at more than twice the rate of the population of the world over the last century.

Lead author Vincent Post, from Flinders  University, said: ‘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.

‘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.’

According to UN Water estimates, water use  has been growing at more than twice the rate of population in the last century  due to demands such as irrigated agriculture and meat production.  More than 40 per cent of the world's  population already live in conditions of water scarcity. By 2030, UN Water  estimates that 47 per cent of people will exist under high water  stress. 

                       
Mr Post said his team's  findings were drawn from a review of seafloor water studies done for  scientific or oil and gas  exploration purposes.

‘By combining all this information we've  demonstrated that the freshwater  below the seafloor is a common finding, and  not some anomaly that only  occurs under very special circumstances,’ he  said.

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.

Post said the deposits were comparable with  the bore basins currently relied upon by much of the world for drinking water  and would cost much less than seawater to desalinate.

Drilling for the water would be expensive,  and Post said great care would have to be taken not to contaminate the aquifers. 

He warned that they were a precious  resource.

‘We should use them carefully: once gone,  they won't be replenished until the sea level drops again, which is not likely  to happen for a very long time,’ Mr Post said.

 *Original story by Willam Turvill at Mail Online via Google News (search term 'Ocean')

Images courtesy of flickr (Leunix)