drilling team member Lalo aguilar working on inner tubes during an expedition 501 wireline core drilling operation aboard the 'Liftboat robert' platform. -- ap
DEEP in Earth's past, an icy landscape became a seascape as the ice melted and the oceans rose off what is now the northeastern United States.
Nearly 50 years ago, a US government ship searching for minerals and hydrocarbons in the area drilled into the seafloor to see what it could find.
It found, of all things, fresh water.
A first-of-its-kind global research expedition is following up on that surprise.
Drilling for fresh water under the salt water off Cape Cod, Expedition 501 extracted thousands of samples from what is now thought to be a massive, hidden aquifer stretching from New Jersey as far north as Maine.
It's just one of many depositories of "secret fresh water" known to exist in shallow salt waters around the world that might some day be tapped to slake the planet's intensifying thirst, said Brandon Dugan, the expedition's co-chief scientist.
Expedition 501memberslooking downfrom the'Liftboatrobertplatform', totheapproachingGaspee, acrew transportvessel, in theNorth atlantic. -- AP
"We need to look for every possibility we have to find more water for society," Dugan, a geophysicist and hydrologist at the Colorado School of Mines, told Associated Press journalists who recently spent 12 hours on the drilling platform.
The research teams looked in "one of the last places you would probably look for fresh water on Earth."
They found it, and will be analysing nearly 50,000 litres of it back in their labs around the world in the coming months.
They're out to solve the mystery of its origins - whether the water is from glaciers, connected groundwater systems on land or some combination.
The potential is enormous. So are the hurdles of getting the water out and puzzling over who owns it, who uses it and how to extract it without undue harm to nature. It's bound to take years to bring that water ashore for public use in a big way, if it's even feasible.
Why try? In just five years, UN says, the global demand for fresh water will exceed supplies by 40%.
Peter emery piloting the 'Gaspee' along the Sakonnet river near portsmouth. -- ap
Rising sea levels from the warming climate are souring coastal freshwater sources while data centres that power AI and cloud computing are consuming water at an insatiable rate.
The fabled Ancient Mariner's lament, "Water, water, every where, nor any drop to drink," looms as a warning to landlubbers as well as to sailors on salty seas.
In Virginia alone, a quarter of all power produced in the state goes to data centres, a share expected to nearly double in five years. By some estimates, each midsize data centre consumes as much water as 1,000 households. Each of the Great Lakes states has experienced groundwater shortages.
Cape Town, South Africa, came perilously close to running out of fresh water for its nearly five million people in 2018 during an epic, three-year drought. South Africa is thought to have a coastal undersea freshwater bonanza, too, and there is at least anecdotal evidence that every continent may have the same.
Canada's Prince Edward Island, Hawaii and Jakarta, Indonesia, are among places where stressed freshwater supplies coexist with prospective aquifers under the ocean.
Jack brickell and alize Longeau extracting samples from a corebefore taking it to the curation container aboard the 'Liftboat robert platform'. -- AP
Enter Expedition 501, a US$25mil scientific collaboration of more than a dozen countries backed by the US government's National Science Foundation and the European Consortium for Ocean Research Drilling (US money for it was secured before budget cuts sought by the Trump administration).
Scientists went into the project believing the undersea aquifer they were sampling might be sufficient to meet the needs of a metropolis the size of New York City for 800 years. They found fresh or nearly fresh water at both higher and lower depths below the seafloor than they anticipated, suggesting a larger supply even than that.
Their work at sea unfolded over three months from Liftboat Robert, an oceangoing vessel that, once on site, lowers three enormous pillars to the seafloor and squats above the waves. Normally it services offshore petroleum sites and wind farms.
This drill-baby-drill mission was different.
"It's known that this phenomena exists both here and elsewhere around the world," Expedition 501 project manager Jez Everest, a scientist who came from the British Geological Survey in Edinburgh, Scotland, said of undersea water.
"But it's a subject that's never been directly investigated by any research project in the past."
By that, he means no one globally had drilled systematically into the seabed on a mission to find freshwater.
Expedition 501 was quite literally groundbreaking - it penetrated Earth below the sea by as many as nearly 400m.
Soon after Robert arrived at the first of three drilling sites on May 19, samples drawn from below the seabed registered salinity of just four parts per thousand. That's far below the oceans' average salt content of 35 parts per thousand but still too briny to meet the US freshwater standard of under one part per thousand.
"Four parts per thousand was a eureka moment," Dugan said, because the finding suggested that the water must have been connected to a terrestrial system in the past, or still is.
As the weeks wore on and Robert moved from site to site 30km to 50km off the coast, the process of drilling into the waterlogged subsea sediment yielded a collection of samples down to one part per thousand salt content. Some were even lower.
Bingo. That's what you find in many bodies of fresh water on land. That's water you can drink, in theory. No one did.
In months of analysis ahead, the scientists will investigate a range of properties of the water, including what microbes were living in the depths, what they used for nutrients and energy sources and what by-products they might generate; in other words, whether the water is safe to consume or otherwise use.
"This is a new environment that has never been studied before," said Jocelyne DiRuggiero, a Johns Hopkins University biologist in Baltimore who studies the microbial ecology of extreme environments and is not involved in the expedition.
"The water may contain minerals detrimental to human health since it percolated through layers of sediments," she said.
"However, a similar process forms the terrestrial aquifers that we use for freshwater, and those typically have very high quality."
By sequencing DNA extracted from their samples, she said, the researchers can determine which micro-organisms are there and "learn how they potentially make a living".
Techniques will also be used to determine whether it came from glacial ice melt thousands of years ago or is still coming via labyrinthian geologic formations from land.
Researchers will date the water back in the lab, and that will be key in determining whether it is a renewable resource that could be used responsibly. Primordial water is trapped and finite; newer water suggests the aquifer is still connected to a terrestrial source and being refreshed, however slowly.
"It's a lesson in how long it can take sometimes to make these things happen and the perseverance that's needed to get there," said Woods Hole geophysicist Rob Evans, whose 2015 expedition helped point the way for 501.
"There's a tonne of excitement that finally they've got samples."
Still, he sees some red flags. One is that tapping undersea aquifers could draw water away from onshore reserves. Another is that undersea groundwater that seeps out to the seafloor may supply nutrients vital to the ecosystem, and that could be upset.
"If we were to go out and start pumping these waters, there would almost certainly be unforeseen consequences," he said. "There's a lot of balance we would need to consider before we started diving in and drilling and exploiting these kinds of things." -- AP