Repurposed Oil Rigs Could Tap Into Ocean Aquifers

Different ideas for re-purposing old oil rigs.
Different ideas for re-purposing old oil rigs.

Oil rigs won’t always be needed… for oil, that is!

Once the oil wells have run dry and our oil and gas drilling rigs stand as hulking monoliths of steel and iron, what will we do with these towering machines? Could we possibly re-purpose drilling platforms to help us extract other resources from below the earth’s surface? Could we keep the rigs intact but retool them to be able to extract fresh water from massive undersea aquifers?

The answer, according to a new study in Nature, states that the continental shelves around the world currently hold more than 500,000 cubic kilometers of fresh, or low-salinity water. Many large cities throughout Asia, Australia, North and South America, and the lower half of Africa are growing at such an alarming rate that access to fresh water supplies is a serious concern.

According to Vincent Post from the US National Center for Groundwater Research:

“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. Knowing about these reserves is great news because this volume of water could sustain some regions for decades.”

Water has been collecting in these underground aquifers for thousands of years, and as the water table has shifted, we’re now seeing that a significant amount of fresh water may be readily accessible given modern drilling technologies. These water reserves have been protected from the seawater by thick layers of clay and sediment that have been collecting on top of the clean water for years.

Two methods have been discussed to access these clean water sources. The first is to build a platform at sea that can drill directly into the seabed. The second option is to drill from the mainland or from islands that are close to the fresh water aquifers. It is thought that oil rigs could be re-purposed and modified to accomplish fresh water drilling. Existing drilling outfits already punch right through aquifers while drilling for gas or oil – some of them ruining the water in the process or using it as a waste reservoir for drilling byproducts.

With our global water supply being used at a rate that is three and a half times greater than it is replenished, finding alternate ways of sourcing fresh water is critical. Nearly a fourth of the earth’s inhabitants rely on existing groundwater supplies for drinking water and irrigation. Accessing these massive aquifers using mostly existing technology will help provide drinking water for millions of people going forward.