Posts Tagged ‘desalination’

Undersea Freshwater Reserves Could Provide Water for Decades

Tuesday, December 17th, 2013

Freshwater is becoming a scarce commodity on Earth. Only 2.5% of the water on Earth is freshwater, and only 0.0325% of that is accessible for drinking. As the population continues to grow, the amount of usable water is quickly disappearing. Some scientists predict a World War could be fought over who gets access to clean water, and water conflicts are already in process in Syria. Thankfully, newfound reserves could sustain the world’s water needs for a while longer.

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 the freshwater pockets for some time but only recently discovered how large they are. Researchers estimate the pockets 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.

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. However, these underground puddles aren’t perfect. The water is briny and will require a fair amount of filtering. Additionally, several problems exist.

The first issue, extracting water from the reserves would be a difficult task. 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.” Secondly, these reserves 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 a 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.

Although the reserves will be a great source of water, it’s just as important to continue being conscientious of our water usage. The water reserves can only be used for so long until they are gone forever, which is why water needs to be used wisely. Conservation is key!