About 71 per cent of the Earth’s surface is occupied by water. Yet, the world faces a drinking water crisis. Most of the surface water is contained in the oceans, and science has long struggled to come up with a solution to convert the salty seawater into clean drinking water for billions of people.
But now, researchers have struck a goldmine of clean water reserve—ironically, that reserve lies beneath the ocean floor. A vast freshwater aquifer has been discovered beneath the Atlantic Ocean off the northeastern United States, a finding that could reshape conversations around global water security.
### A Hidden Freshwater Reserve Beneath the Sea
Reports say that a team of scientists drilled more than 1,000 feet below the seafloor and confirmed the presence of water far less saline than seawater—at a level approaching what international agencies classify as drinkable.
The existence of offshore freshwater beneath the ocean floor has been suspected for decades. In the 1960s and 1970s, companies searching for oil and gas stumbled upon pockets of fresh water, but these anomalies were not systematically investigated.
In 2019, scientists from Woods Hole Oceanographic Institution and Columbia University used electromagnetic imaging to map what appeared to be a massive body of fresh water stretching from Massachusetts to New Jersey, possibly even further. This early mapping suggested it might be the largest formation of its kind known anywhere in the world.
### A Global Thirst for Solutions
The discovery comes at a time when water scarcity is worsening across continents. *Earth* journal reported that global demand for fresh water is projected to exceed supply by 40 per cent in the coming years.
Coastal aquifers—on which hundreds of millions depend—are under severe stress due to over-extraction and contamination from rising seas. As Cape Town’s brush with “Day Zero” in 2018 demonstrated, even modern cities are vulnerable to running dry.
Against this backdrop, scientists are looking to unconventional sources. Undersea aquifers, once dismissed as inaccessible, are now being studied as possible lifelines for coastal populations. Nearly half of the world’s people live within 60 miles of a coastline, meaning offshore resources could one day play a significant role in water security.
### Expedition 501: Drilling into the Mystery
To move from speculation to evidence, an international team launched **Expedition 501** in May 2023. The project, backed by the US National Science Foundation and European research institutions, set out from Connecticut aboard a specialized liftboat known as *Robert*.
Usually used for oil and wind projects, the vessel was refitted as a floating geology lab. Over three months, scientists drilled as deep as 400 metres into the seabed, extracting thousands of sediment cores and nearly 50,000 liters of water samples.
According to geophysics professor Brandon Dugan of the Colorado School of Mines, the expedition’s aim was to answer fundamental questions: How old is the water? Is it being replenished? Where did it originate?
### How Did Freshwater Get There?
The origins of the undersea aquifer remain under investigation. Holly Michael, a University of Delaware scientist involved in the drilling, explained one hypothesis suggesting that the water seeped underground thousands of years ago, when sea levels were lower and parts of the continental shelf were exposed as dry land.
Another theory is that the aquifer may be partially recharged today by modern rainfall and terrestrial groundwater slowly migrating offshore. The truth may be a mixture of both.
According to *Earth*, if the aquifer mainly contains meltwater from the last Ice Age, then it is essentially non-renewable and must be treated as a fossil resource. If it remains connected to coastal aquifers, then pumping from offshore could affect onshore hydrology, potentially worsening saltwater intrusion.
### A Reservoir Vast Enough for Cities
Early assessments suggest the aquifer is enormous. Eric Attias of the University of Texas at Austin, who was not part of the expedition, told CNN that the reservoir might contain enough freshwater to supply a metropolis the size of New York City for centuries.
This prospect has raised hopes that offshore aquifers could relieve pressure on stressed groundwater supplies in coastal regions worldwide.
Previous surveys had hinted at this potential. A 2015 electromagnetic imaging study suggested that the aquifer beneath the US Atlantic margin might rival the Ogallala Aquifer in the Great Plains, one of the largest known groundwater reserves on land.
The recent drilling campaign has now confirmed those hints with physical samples.
### Hurdles and Risks
Despite the promise, experts caution against over-optimism. Michael emphasized that extracting water from offshore aquifers will be energy-intensive and expensive. Water is heavy, and transporting it to shore would require major infrastructure investments.
Some researchers suggest that renewable energy sources such as offshore wind might help offset the energy cost.
Technical challenges also loom large. Engineers would need to ensure that pumping does not draw saltwater into the fresh reservoir or collapse the sediments around the wells. There are also risks of cross-contamination between offshore and onshore aquifers if they are hydraulically connected.
Ecologists warn that altering underground pressure systems could affect coastal habitats and springs.
### Legal and Political Questions
Even if the technology matures, thorny governance issues remain unresolved. The aquifer lies beneath federal waters, raising questions about who would own and manage the water and how it would be distributed among states and municipalities.
Policymakers will need to determine how indigenous communities, fishing industries, and coastal populations fit into the decision-making process. Funding, regulation, and environmental safeguards would all have to be negotiated.
### A 10-Year Horizon
Despite these hurdles, researchers remain cautiously hopeful. Dugan estimates it could take around a decade before offshore aquifers could realistically be tapped as a municipal resource.
The team is currently conducting lab tests to determine the water’s microbial content, isotopic age, and geochemical signatures. These results, expected within months, will clarify whether the aquifer is a fossil relic or a living, recharging system.
Michael remarked that safeguarding terrestrial aquifers remains the most effective strategy, but exploring alternative options like undersea reserves could provide a critical backup in an era of climate stress.
### A Global Potential
The Atlantic aquifer may be just the beginning. Evidence suggests similar offshore freshwater reserves exist near South Africa, Australia, Indonesia, Canada, and Hawaii.
If confirmed, these hidden resources could form a global network of emergency supplies.
According to Dugan, lessons learned from the US northeast coast could help scientists evaluate offshore reservoirs on every continent.
### Water, Water Everywhere?
The irony of using oil-field technology to search for drinking water is not lost on the scientists involved. The same drilling rigs once devoted to hydrocarbons are now probing for one of humanity’s most basic needs.
As *Earth* described, the expedition represents both a continuation of decades of scattered clues and a response to a very modern urgency: a world where fresh water is running short even as oceans surround us.
Whether these undersea aquifers become a cornerstone of water security or remain scientific curiosities will depend on what the next rounds of testing reveal. For now, the samples pulled from beneath the Atlantic stand as both evidence and promise — a submerged storehouse that could one day help quench a thirsty planet.
https://www.firstpost.com/world/atlantic-ocean-drinking-water-fossil-reserve-13935004.html