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A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs

News Feed
Tuesday, September 10, 2024

Germany’s North and Baltic Seas are littered with munitions from the First and Second World Wars, such as shells—as shown here—once fired from German battleships. SeaTerra Aboard the Alkor, a 180-foot oceanographic vessel anchored in the Baltic Sea a few miles from the German port city of Kiel, engineer Henrik Schönheit grips a joystick-like lever in his fist. He nudges the lever up, and a one-of-a-kind robotic sea crawler about the size of a two-seat golf cart responds, creeping forward along the seafloor on rubber caterpillar tracks 40 feet below the ship. As the crawler inspects Kiel Bay’s sandy terrain, a live video stream beams up to a computer screen in a cramped room aboard the ship. The picture is so crystalline that it’s possible to count the tentacles of a translucent jellyfish floating past the camera. A scrum of scientists and technicians ooh and aah as they huddle around the screen, peering over Schönheit’s shoulder. The bright-yellow robot is the Norppa 300, the newest fabrication of the explosive ordnance disposal company SeaTerra, which operates out of northern Germany. SeaTerra’s co-founder Dieter Guldin rates as one of Europe’s canniest experts on salvaging sunken explosives. Now, after years of experience clearing the seafloor of hazards for commercial operations, and campaigning the German government for large-scale remediation, SeaTerra is one of three companies participating in the first-ever mission to systematically clear munitions off a seafloor in the name of environmental protection. The arduous and exacting process of removing and destroying more than 1.6 million tons of volatile munitions from the Baltic and North Sea basins—an area roughly the size of West Virginia—is more urgent by the day: The weapons, which have killed hundreds of people who have come into accidental contact with them in the past, are now corroded. Their casings are breaking apart and releasing carcinogens into the seas. Onboard the Alkor, during a test run this May, SeaTerra technicians Klaus-Dieter Golla, left, and Henrik Schönheit discuss video footage of the seafloor transmitted by the company’s Norppa 300 robot. Andreas Muenchbach SeaTerra’s top technicians aboard the Alkor are testing the Norppa 300’s basic functions in the wild prior to the project’s start this month, in early September 2024: ensuring that its steering, sonar imaging of the seafloor, chemical sampler and video feed are fine-tuned. Everyone huddled in the ship’s dry lab watches rapt as the crawler bumps up against a vaguely rectangular object the size of a bar fridge. It’s largely obscured by seaweed and, from the looks of it, home to a lone Baltic flounder that’s swimming around the base. Aaron Beck, senior scientist at the Geomar Helmholtz Center for Ocean Research, a German marine research institute working alongside SeaTerra, identifies it as an ammunition crate. “Look, the flatness there, the corner. That’s not of the natural world,” he exclaims. Dumped munitions lie in waters around the world but are ubiquitous in German waters. In the aftermath of World War II, all the conflict parties, including the United Kingdom, Russia, Japan and the United States, had to divest themselves of armaments. “They didn’t want [them] on land, and facilities to destroy [them] were too few,” explains Anita Künitzer of the German Environment Agency. Dumping at sea, a practice held over from World War I, was the obvious choice. In occupied Germany, British forces established underwater disposal zones—one of which lies near Kiel Bay. “But,” says Guldin, “on their way to the designated dumping grounds, they also just threw hardware overboard.” Grainy black-and-white film footage shows British sailors busily operating multiple conveyor belts to cast crate after crate of leftovers into the sea. Whole ships and submarines packed with live munitions were scuttled in the rush to disarm the Germans. 1500 Miles Of Bombs Along Our Roads Aka Ammunition Dumps Or Arms Dump (1946) Experts estimate that a ginormous 1.8 million tons of conventional munitions and another 5,500 tons of chemical weapons lie decomposing off Germany alone in the North and Baltic Seas, most from World War II. (Because of its busy ports, the North Sea received four times as much as the Baltic.) If all that weaponry were lined up, it would stretch from Paris to Moscow, about 1,500 miles! “Nowhere in German waters is there a square kilometer of seabed without munitions,” says Guldin. In the postwar decades, freelancing scrap metal collectors hauled explosives and other valuable wartime debris ashore to hawk on the metals market. Fisher boats that ensnared unexploded munitions in their nets were required to turn them in to coastal authorities, not toss them overboard again. The German Navy’s anti-mine units attempted to clear some of the mess, usually through initiating underwater explosions, but lacked the proper equipment to tackle the problem systematically. Only when the private sector picked up operations did a whole new suite of technology and skill sets emerge. Since the late 2000s, SeaTerra’s ensemble of marine biologists, hydraulic specialists, sedimentologists, divers, engineers, geophysicists, marine surveyors, pyrotechnicians and archaeologists—now about 160 people—have been mapping the sunken armaments as they worked to clear safe patches of seafloor for wind-farm, cable and pipeline projects. But until this year, SeaTerra never possessed the remit it has long coveted: to begin systematically ameliorating the seafloor for the sake of marine ecosystems—and the people dependent on them. The German government has set aside 100 million euros (over $110 million) to remove the toxic mess from Lübeck Bay, off the Baltic port city of Lübeck, southeast of Kiel, as a pilot project. “No other country in the world has ever attempted or achieved this,” says Tobias Goldschmidt, the region’s environment minister, in a press release. Experts prepare the Norppa 300 for a trial run in the Baltic Sea in May. Andreas Muenchbach Guldin and other advocates are elated that the project is on, but they acknowledge it will only dent the Baltic’s total quantity of submerged ordnance. Their goal is to recover between 55 and 88 tons worth of munitions, though the pilot’s primary purpose is for SeaTerra and the two other firms to test their technology and to demonstrate to bankrollers that the job is doable. “Then it’s about scaling up and getting faster,” says Guldin. Faster is vital, because in their watery graves, the many land and naval mines, U-boat torpedoes, depth charges, artillery shells, chemical weapons, aerial bombs, and incendiary devices have corroded over almost 80 years. The Germans, like other dumping nations, long assumed that when the casings broke down, the vast ocean would simply dissolve pollutants into harmless fractions. About 25 years ago, scientists discovered that instead, the explosives remain live and are now oozing into the ecosystem and up the food chain. That flounder darting in front of the crawler’s camera from the Alkor’s dry lab? It almost certainly contains traces of TNT, the highly toxic compound used in explosives. Toxicologist Jennifer Strehse, from the Kiel-based Institute of Toxicology and Pharmacology for Natural Scientists, which identified the mounting toxic pollution, says that contamination is particularly widespread in shellfish, bottom-dwelling flatfish and other fauna that are close to the munition dumps. They’re “contaminated with carcinogens from TNT or arsenic or heavy metals like lead and mercury,” she says. An image of Lübeck bay’s seafloor shows a smattering of bombs. Geomar Helmholtz Centre for Ocean Research Scientists have also found toxic concentrations of TNT in Atlantic purple sea urchins, mysid crustaceans and blue mussels. Once contaminants have escaped into the water, they can’t be recovered, Strehse points out. “So, we’re working against time.” German health experts recommend that consumers limit themselves to no more than two meals of local fish a week to reduce exposure to heavy metals, dioxins or PCBs. The source of most of these contaminants are industrial processes and the burning of fossil fuels; TNT does not figure into the guidelines. Nevertheless, the risk of TNT and other contaminants from weapons is enough to cause Strehse, herself, to steer clear of all Baltic Sea mussels. The risk of immediate loss of life is also ever-present. Most of the submerged weapons remain as powerful as the day they were dumped. Now rusted through, they are even more unstable—presenting a precarious obstacle to fishing boats trawling the seafloor as well as offshore wind-farm developers, whose sprawling turbine parks are integral to Europe’s transition to clean energy systems. In the two German seas, over 400 people—tourists, sailors, fishers, naval cadets and munitions experts—have lost their lives to explosions from sunken weapons. German aerial bombs retrieved from the Baltic Sea are stacked and secured before the SeaTerra team transports them ashore for disposal. Germany currently has only one major disposal facility for unexploded ordnance. SeaTerra The menace doesn’t stay at sea, either. As the munitions deteriorate, amber-colored chunks of phosphorous from incendiary bombs, fragments of TNT or rusted casings often wash up on shore. Beachcombers who touch solid white phosphorus—usually mistaking it for Baltic amber, a sought-after gemstone—can suffer third-degree burns or worse. The chemical element sticks to human skin and can combust spontaneously when exposed to air at temperatures above 86 degrees Fahrenheit. Over half a century after the fighting ended, the task of addressing the environmental danger and risk to life from dumped munitions has become its own battle. When Guldin entered the field of munitions cleanup in 2000, he saw the problem’s vastness and malevolent power as the ultimate challenge for his technical imagination. Fifty-seven-year-old Guldin describes himself as a pacifist by nature and archaeologist by training. He grew up far removed from oceans, in southern Germany’s Black Forest where, as a conscientious objector, he refused to serve in the German Army, later joining the Green Party instead. He helped excavate Roman settlements along the Rhine River. Then he moved on to the Middle East, where he unearthed ancient civilizations in Yemen and Lebanon. Eventually, in 2000, he admitted to himself that the long stays abroad and one-off digs weren’t conducive to the family life he wanted. Shortly after this, he touched base with an old friend, Edgar Schwab. Dieter Guldin of SeaTerra has been encouraging the German government to clean up sunken war munitions for years. Drones Magazin Schwab, a geophysicist, was in Hamburg, Germany, and one step ahead of his buddy—starting up a little company to appropriate the lethal relics of the Third Reich from the ocean floor. The two friends were less interested in digging to explain humanity’s past than in undoing the damage it had inflicted upon nature, and together they co-founded SeaTerra. Guldin immersed himself in the history of munitions dumping in Northern Europe—a practice that was discontinued worldwide only in 1975. While SeaTerra conscientiously cleared patches of seafloor for industry, the mass of munitions across the greater seafloor gnawed at him. He insisted that his country clean it up so that future generations wouldn’t suffer this legacy of wars executed by generations past. He worked the halls of power for ten years but couldn’t get officialdom to touch the odious issue. The fact that the seafloor was littered with munitions has been common knowledge since 1945, but no one knew exactly how much there was or where. SeaTerra and a smorgasbord of concerned groups, including Strehse’s institute, understood that before anybody was going to address the issue, they first had to find out exactly what they were dealing with. In the course of its work for private companies, SeaTerra began developing technology—such as a prototype crawler, the DeepC—for surveying the seafloor, foot by excruciating foot. In the deep and churning North Sea, with its muscular tidal currents, much of the detritus lies yards beneath the seafloor. To penetrate the sediment, SeaTerra developed underwater drones and advanced multibeam radar equipment. For shallow tidal areas, SeaTerra also created low-flying drones outfitted with magnetic sensors that can detect metallic masses buried deep in the sand. SeaTerra technicians lower a device called a ScanFish. They use it to tow magnetic sensors through the water, about six feet above the seafloor. SeaTerra Many of SeaTerra’s innovations entailed modifying technology used in related fields, like mining, pyrotechnics and archaeology. The team started with a lot of energy but few resources: “In the beginning, we used zip ties and duct tape for everything,” Guldin says. The range of state-of-the-art technology the team now operates is not the brainchild of one person, but Guldin has been central to much of it. Now, with a firm grasp of the problem and how to address it, Guldin and others at SeaTerra are itching to display their accumulated know-how in Lübeck Bay. “The time has now come,” he announced recently on LinkedIn. “We, the explosive ordnance disposal companies, can now start our real work to make the oceans cleaner … and to measure our ideas and concepts against the physical reality of this blight.” It is, his announcement says, a great success for the company and a “recognition of our many years of effort in developing new technologies and concepts for explosive ordnance at sea.” Aboard the Alkor, the scientists believe their star, the Norppa 300, is ready for official deployment in Lübeck Bay. The crawler is the culmination of years of invention, testing and tweaking. Unlike previous undersea robots, it operates at depths up to almost 1,000 feet and can do so 24/7, even in turbulent waters. Its many functions will relieve professional divers of some of the cleanup expedition’s most perilous tasks. The robot is equipped with sonar and acoustic imaging for detecting and identifying buried munitions. Its detachable arms include a custom-designed vacuum that gingerly sucks up sediment from buried explosives and a pincer for lifting pieces of ammunition. The cleanup process for weapons that can be handled will involve three general steps using specialized ships. First, SeaTerra’s engineers and scientists on the Alkor—the survey vessel—will scan the site and classify the munitions. They will also take water samples for the Geomar Helmholtz Center to analyze on board, distinguishing conventional from chemical weaponry. Chemical weapons, which contain phosgene, arsenic and sulfur mustard (also known as mustard gas), are too lethal to handle, probably ever, admits Guldin. “You can’t see these gases or smell them,” he says, “and their detonation could blow a ship out of the water, killing a ship’s entire crew in a matter of minutes.” Those weapons will be left untouched. Aaron Beck of Geomar Helmholtz Center for Ocean Research stands beside a mass spectrometer, used to analyze the chemical contents of water samples, in the Alkor’s dry lab. Andreas Muenchbach Künitzer of the environment agency adds that the Nazis’ nerve gases were designed to incapacitate the eyes, skin and lungs of battlefield foes. “Decades underwater doesn’t dilute their potency,” she says. If the experts determine the material is safe enough for transportation, they’ll deploy the Norppa 300 to collect and deposit smaller items, like grenades, into undersea wire-mesh baskets. But if the explosive specialists monitoring from the ship above determine that the weaponry still contains detonators, divers—not a robot—will be sent to detach them. This is hazardous business that, thus far, only humans can execute. Next, a different team on a second ship—the clearance vessel—equipped with spud legs (stakes that hold the ship in place) will use a hydraulic crane equipped with cameras to extract larger munitions, including those with corrupted casings, and drop them into undersea receptacles. The final step is for a third team to haul the cargo onto the deck of their ship—the sorting vessel—to sort, label and package the lethal concoctions in steel tubes, and then transport them to an interim site in the Baltic Sea. There the material will be re-sunk in the tubes and stored underwater until it can be handed over to the responsible state authority, the Explosive Ordnance Disposal Service, for demolition. Some of the munitions SeaTerra clears from Germany’s seas date back to World War I, such as the six-inch-long cast iron shell shown here. SeaTerra The workers will have two months to clear the bay—and demonstrate whether the Norppa 300 and other technologies are either up to it or not. But there’s a hitch that will delay the destruction of all of the recovered weapons for about a year. Germany has a single major munitions disposal facility, and it is occupied with incinerating unexploded ordnance from around the globe, not least, incredibly, Nazi-era explosives still being unearthed from construction sites. That’s why the Lübeck Bay project’s budget includes construction of a disposal facility. The company and concept have yet to be finalized. One option is to build a floating clearance platform where robots would dissect ordnance and burn the chemical contents in a detonation chamber at temperatures of over 2300 degrees Fahrenheit, similar to how weapons are disposed of at the land-based facility. And there’s another issue. Over the years, the mounds of weaponry in the undersea dumping grounds have corroded and collapsed into one another, creating a gnarled, combustible mass of metals and explosive agents that make their recovery more complicated. The only options are to leave these or blow them up on-site. The best-case scenario is that all the Baltic’s most hazardous conventional munitions will finally be history by 2050, and work on the North Sea will be well underway. The worst case is that funding does not materialize and the mountains of explosives will continue to deteriorate en masse, emitting poisons. Before the green light came to start the cleanup, Guldin was becoming doubtful his country would ever address the mess, and he thought he might have to accept that SeaTerra’s expertise would never be put to the greater task that he and Schwab had envisioned. For the foreseeable future at least, he’ll be in the thick of culminating his life’s work, undoing some of humanity’s sins on the seafloor. This article is from Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com. Related stories from Hakai Magazine: • Weapons of War Litter the Ocean Floor • Why Ocean Shores Beachcombing Is a Blast Get the latest stories in your inbox every weekday.

The ocean became a dumping ground for weapons after Allied forces defeated the Nazis. Now a team of robots and divers is making the waters safer

header-uncropped-robots-and-war-munitions.jpg
Germany’s North and Baltic Seas are littered with munitions from the First and Second World Wars, such as shells—as shown here—once fired from German battleships. SeaTerra

Aboard the Alkor, a 180-foot oceanographic vessel anchored in the Baltic Sea a few miles from the German port city of Kiel, engineer Henrik Schönheit grips a joystick-like lever in his fist. He nudges the lever up, and a one-of-a-kind robotic sea crawler about the size of a two-seat golf cart responds, creeping forward along the seafloor on rubber caterpillar tracks 40 feet below the ship. As the crawler inspects Kiel Bay’s sandy terrain, a live video stream beams up to a computer screen in a cramped room aboard the ship. The picture is so crystalline that it’s possible to count the tentacles of a translucent jellyfish floating past the camera. A scrum of scientists and technicians ooh and aah as they huddle around the screen, peering over Schönheit’s shoulder.

The bright-yellow robot is the Norppa 300, the newest fabrication of the explosive ordnance disposal company SeaTerra, which operates out of northern Germany. SeaTerra’s co-founder Dieter Guldin rates as one of Europe’s canniest experts on salvaging sunken explosives. Now, after years of experience clearing the seafloor of hazards for commercial operations, and campaigning the German government for large-scale remediation, SeaTerra is one of three companies participating in the first-ever mission to systematically clear munitions off a seafloor in the name of environmental protection. The arduous and exacting process of removing and destroying more than 1.6 million tons of volatile munitions from the Baltic and North Sea basins—an area roughly the size of West Virginia—is more urgent by the day: The weapons, which have killed hundreds of people who have come into accidental contact with them in the past, are now corroded. Their casings are breaking apart and releasing carcinogens into the seas.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
Onboard the Alkor, during a test run this May, SeaTerra technicians Klaus-Dieter Golla, left, and Henrik Schönheit discuss video footage of the seafloor transmitted by the company’s Norppa 300 robot. Andreas Muenchbach

SeaTerra’s top technicians aboard the Alkor are testing the Norppa 300’s basic functions in the wild prior to the project’s start this month, in early September 2024: ensuring that its steering, sonar imaging of the seafloor, chemical sampler and video feed are fine-tuned. Everyone huddled in the ship’s dry lab watches rapt as the crawler bumps up against a vaguely rectangular object the size of a bar fridge. It’s largely obscured by seaweed and, from the looks of it, home to a lone Baltic flounder that’s swimming around the base. Aaron Beck, senior scientist at the Geomar Helmholtz Center for Ocean Research, a German marine research institute working alongside SeaTerra, identifies it as an ammunition crate. “Look, the flatness there, the corner. That’s not of the natural world,” he exclaims.


Dumped munitions lie in waters around the world but are ubiquitous in German waters. In the aftermath of World War II, all the conflict parties, including the United Kingdom, Russia, Japan and the United States, had to divest themselves of armaments. “They didn’t want [them] on land, and facilities to destroy [them] were too few,” explains Anita Künitzer of the German Environment Agency. Dumping at sea, a practice held over from World War I, was the obvious choice.

In occupied Germany, British forces established underwater disposal zones—one of which lies near Kiel Bay. “But,” says Guldin, “on their way to the designated dumping grounds, they also just threw hardware overboard.” Grainy black-and-white film footage shows British sailors busily operating multiple conveyor belts to cast crate after crate of leftovers into the sea. Whole ships and submarines packed with live munitions were scuttled in the rush to disarm the Germans.

1500 Miles Of Bombs Along Our Roads Aka Ammunition Dumps Or Arms Dump (1946)

Experts estimate that a ginormous 1.8 million tons of conventional munitions and another 5,500 tons of chemical weapons lie decomposing off Germany alone in the North and Baltic Seas, most from World War II. (Because of its busy ports, the North Sea received four times as much as the Baltic.) If all that weaponry were lined up, it would stretch from Paris to Moscow, about 1,500 miles! “Nowhere in German waters is there a square kilometer of seabed without munitions,” says Guldin.

In the postwar decades, freelancing scrap metal collectors hauled explosives and other valuable wartime debris ashore to hawk on the metals market. Fisher boats that ensnared unexploded munitions in their nets were required to turn them in to coastal authorities, not toss them overboard again. The German Navy’s anti-mine units attempted to clear some of the mess, usually through initiating underwater explosions, but lacked the proper equipment to tackle the problem systematically. Only when the private sector picked up operations did a whole new suite of technology and skill sets emerge.

Since the late 2000s, SeaTerra’s ensemble of marine biologists, hydraulic specialists, sedimentologists, divers, engineers, geophysicists, marine surveyors, pyrotechnicians and archaeologists—now about 160 people—have been mapping the sunken armaments as they worked to clear safe patches of seafloor for wind-farm, cable and pipeline projects.

But until this year, SeaTerra never possessed the remit it has long coveted: to begin systematically ameliorating the seafloor for the sake of marine ecosystems—and the people dependent on them. The German government has set aside 100 million euros (over $110 million) to remove the toxic mess from Lübeck Bay, off the Baltic port city of Lübeck, southeast of Kiel, as a pilot project. “No other country in the world has ever attempted or achieved this,” says Tobias Goldschmidt, the region’s environment minister, in a press release.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
Experts prepare the Norppa 300 for a trial run in the Baltic Sea in May. Andreas Muenchbach

Guldin and other advocates are elated that the project is on, but they acknowledge it will only dent the Baltic’s total quantity of submerged ordnance. Their goal is to recover between 55 and 88 tons worth of munitions, though the pilot’s primary purpose is for SeaTerra and the two other firms to test their technology and to demonstrate to bankrollers that the job is doable. “Then it’s about scaling up and getting faster,” says Guldin.


Faster is vital, because in their watery graves, the many land and naval mines, U-boat torpedoes, depth charges, artillery shells, chemical weapons, aerial bombs, and incendiary devices have corroded over almost 80 years. The Germans, like other dumping nations, long assumed that when the casings broke down, the vast ocean would simply dissolve pollutants into harmless fractions. About 25 years ago, scientists discovered that instead, the explosives remain live and are now oozing into the ecosystem and up the food chain.

That flounder darting in front of the crawler’s camera from the Alkor’s dry lab? It almost certainly contains traces of TNT, the highly toxic compound used in explosives. Toxicologist Jennifer Strehse, from the Kiel-based Institute of Toxicology and Pharmacology for Natural Scientists, which identified the mounting toxic pollution, says that contamination is particularly widespread in shellfish, bottom-dwelling flatfish and other fauna that are close to the munition dumps. They’re “contaminated with carcinogens from TNT or arsenic or heavy metals like lead and mercury,” she says.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
An image of Lübeck bay’s seafloor shows a smattering of bombs. Geomar Helmholtz Centre for Ocean Research

Scientists have also found toxic concentrations of TNT in Atlantic purple sea urchins, mysid crustaceans and blue mussels. Once contaminants have escaped into the water, they can’t be recovered, Strehse points out. “So, we’re working against time.”

German health experts recommend that consumers limit themselves to no more than two meals of local fish a week to reduce exposure to heavy metals, dioxins or PCBs. The source of most of these contaminants are industrial processes and the burning of fossil fuels; TNT does not figure into the guidelines. Nevertheless, the risk of TNT and other contaminants from weapons is enough to cause Strehse, herself, to steer clear of all Baltic Sea mussels.

The risk of immediate loss of life is also ever-present. Most of the submerged weapons remain as powerful as the day they were dumped. Now rusted through, they are even more unstable—presenting a precarious obstacle to fishing boats trawling the seafloor as well as offshore wind-farm developers, whose sprawling turbine parks are integral to Europe’s transition to clean energy systems. In the two German seas, over 400 people—tourists, sailors, fishers, naval cadets and munitions experts—have lost their lives to explosions from sunken weapons.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
German aerial bombs retrieved from the Baltic Sea are stacked and secured before the SeaTerra team transports them ashore for disposal. Germany currently has only one major disposal facility for unexploded ordnance. SeaTerra

The menace doesn’t stay at sea, either. As the munitions deteriorate, amber-colored chunks of phosphorous from incendiary bombs, fragments of TNT or rusted casings often wash up on shore. Beachcombers who touch solid white phosphorus—usually mistaking it for Baltic amber, a sought-after gemstone—can suffer third-degree burns or worse. The chemical element sticks to human skin and can combust spontaneously when exposed to air at temperatures above 86 degrees Fahrenheit.

Over half a century after the fighting ended, the task of addressing the environmental danger and risk to life from dumped munitions has become its own battle. When Guldin entered the field of munitions cleanup in 2000, he saw the problem’s vastness and malevolent power as the ultimate challenge for his technical imagination.


Fifty-seven-year-old Guldin describes himself as a pacifist by nature and archaeologist by training. He grew up far removed from oceans, in southern Germany’s Black Forest where, as a conscientious objector, he refused to serve in the German Army, later joining the Green Party instead. He helped excavate Roman settlements along the Rhine River. Then he moved on to the Middle East, where he unearthed ancient civilizations in Yemen and Lebanon. Eventually, in 2000, he admitted to himself that the long stays abroad and one-off digs weren’t conducive to the family life he wanted. Shortly after this, he touched base with an old friend, Edgar Schwab.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
Dieter Guldin of SeaTerra has been encouraging the German government to clean up sunken war munitions for years. Drones Magazin

Schwab, a geophysicist, was in Hamburg, Germany, and one step ahead of his buddy—starting up a little company to appropriate the lethal relics of the Third Reich from the ocean floor. The two friends were less interested in digging to explain humanity’s past than in undoing the damage it had inflicted upon nature, and together they co-founded SeaTerra.

Guldin immersed himself in the history of munitions dumping in Northern Europe—a practice that was discontinued worldwide only in 1975. While SeaTerra conscientiously cleared patches of seafloor for industry, the mass of munitions across the greater seafloor gnawed at him. He insisted that his country clean it up so that future generations wouldn’t suffer this legacy of wars executed by generations past. He worked the halls of power for ten years but couldn’t get officialdom to touch the odious issue.

The fact that the seafloor was littered with munitions has been common knowledge since 1945, but no one knew exactly how much there was or where. SeaTerra and a smorgasbord of concerned groups, including Strehse’s institute, understood that before anybody was going to address the issue, they first had to find out exactly what they were dealing with.

In the course of its work for private companies, SeaTerra began developing technology—such as a prototype crawler, the DeepC—for surveying the seafloor, foot by excruciating foot. In the deep and churning North Sea, with its muscular tidal currents, much of the detritus lies yards beneath the seafloor. To penetrate the sediment, SeaTerra developed underwater drones and advanced multibeam radar equipment. For shallow tidal areas, SeaTerra also created low-flying drones outfitted with magnetic sensors that can detect metallic masses buried deep in the sand.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
SeaTerra technicians lower a device called a ScanFish. They use it to tow magnetic sensors through the water, about six feet above the seafloor. SeaTerra

Many of SeaTerra’s innovations entailed modifying technology used in related fields, like mining, pyrotechnics and archaeology. The team started with a lot of energy but few resources: “In the beginning, we used zip ties and duct tape for everything,” Guldin says. The range of state-of-the-art technology the team now operates is not the brainchild of one person, but Guldin has been central to much of it.

Now, with a firm grasp of the problem and how to address it, Guldin and others at SeaTerra are itching to display their accumulated know-how in Lübeck Bay. “The time has now come,” he announced recently on LinkedIn. “We, the explosive ordnance disposal companies, can now start our real work to make the oceans cleaner … and to measure our ideas and concepts against the physical reality of this blight.” It is, his announcement says, a great success for the company and a “recognition of our many years of effort in developing new technologies and concepts for explosive ordnance at sea.”


Aboard the Alkor, the scientists believe their star, the Norppa 300, is ready for official deployment in Lübeck Bay. The crawler is the culmination of years of invention, testing and tweaking. Unlike previous undersea robots, it operates at depths up to almost 1,000 feet and can do so 24/7, even in turbulent waters. Its many functions will relieve professional divers of some of the cleanup expedition’s most perilous tasks. The robot is equipped with sonar and acoustic imaging for detecting and identifying buried munitions. Its detachable arms include a custom-designed vacuum that gingerly sucks up sediment from buried explosives and a pincer for lifting pieces of ammunition.

The cleanup process for weapons that can be handled will involve three general steps using specialized ships. First, SeaTerra’s engineers and scientists on the Alkor—the survey vesselwill scan the site and classify the munitions. They will also take water samples for the Geomar Helmholtz Center to analyze on board, distinguishing conventional from chemical weaponry. Chemical weapons, which contain phosgene, arsenic and sulfur mustard (also known as mustard gas), are too lethal to handle, probably ever, admits Guldin. “You can’t see these gases or smell them,” he says, “and their detonation could blow a ship out of the water, killing a ship’s entire crew in a matter of minutes.” Those weapons will be left untouched.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
Aaron Beck of Geomar Helmholtz Center for Ocean Research stands beside a mass spectrometer, used to analyze the chemical contents of water samples, in the Alkor’s dry lab. Andreas Muenchbach

Künitzer of the environment agency adds that the Nazis’ nerve gases were designed to incapacitate the eyes, skin and lungs of battlefield foes. “Decades underwater doesn’t dilute their potency,” she says.

If the experts determine the material is safe enough for transportation, they’ll deploy the Norppa 300 to collect and deposit smaller items, like grenades, into undersea wire-mesh baskets. But if the explosive specialists monitoring from the ship above determine that the weaponry still contains detonators, divers—not a robot—will be sent to detach them. This is hazardous business that, thus far, only humans can execute.

Next, a different team on a second ship—the clearance vessel—equipped with spud legs (stakes that hold the ship in place) will use a hydraulic crane equipped with cameras to extract larger munitions, including those with corrupted casings, and drop them into undersea receptacles. The final step is for a third team to haul the cargo onto the deck of their ship—the sorting vessel—to sort, label and package the lethal concoctions in steel tubes, and then transport them to an interim site in the Baltic Sea. There the material will be re-sunk in the tubes and stored underwater until it can be handed over to the responsible state authority, the Explosive Ordnance Disposal Service, for demolition.

A Massive Effort Is Underway to Rid the Baltic Sea of Sunken Bombs
Some of the munitions SeaTerra clears from Germany’s seas date back to World War I, such as the six-inch-long cast iron shell shown here. SeaTerra

The workers will have two months to clear the bay—and demonstrate whether the Norppa 300 and other technologies are either up to it or not.

But there’s a hitch that will delay the destruction of all of the recovered weapons for about a year. Germany has a single major munitions disposal facility, and it is occupied with incinerating unexploded ordnance from around the globe, not least, incredibly, Nazi-era explosives still being unearthed from construction sites. That’s why the Lübeck Bay project’s budget includes construction of a disposal facility. The company and concept have yet to be finalized. One option is to build a floating clearance platform where robots would dissect ordnance and burn the chemical contents in a detonation chamber at temperatures of over 2300 degrees Fahrenheit, similar to how weapons are disposed of at the land-based facility.

And there’s another issue. Over the years, the mounds of weaponry in the undersea dumping grounds have corroded and collapsed into one another, creating a gnarled, combustible mass of metals and explosive agents that make their recovery more complicated. The only options are to leave these or blow them up on-site. The best-case scenario is that all the Baltic’s most hazardous conventional munitions will finally be history by 2050, and work on the North Sea will be well underway. The worst case is that funding does not materialize and the mountains of explosives will continue to deteriorate en masse, emitting poisons.

Before the green light came to start the cleanup, Guldin was becoming doubtful his country would ever address the mess, and he thought he might have to accept that SeaTerra’s expertise would never be put to the greater task that he and Schwab had envisioned. For the foreseeable future at least, he’ll be in the thick of culminating his life’s work, undoing some of humanity’s sins on the seafloor.

This article is from Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com.

Related stories from Hakai Magazine:

Weapons of War Litter the Ocean Floor

Why Ocean Shores Beachcombing Is a Blast

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Hungary's 'Water Guardian' Farmers Fight Back Against Desertification

Southern Hungary landowner Oszkár Nagyapáti has been battling severe drought on his land

KISKUNMAJSA, Hungary (AP) — Oszkár Nagyapáti climbed to the bottom of a sandy pit on his land on the Great Hungarian Plain and dug into the soil with his hand, looking for a sign of groundwater that in recent years has been in accelerating retreat. “It’s much worse, and it’s getting worse year after year,” he said as cloudy liquid slowly seeped into the hole. ”Where did so much water go? It’s unbelievable.”Nagyapáti has watched with distress as the region in southern Hungary, once an important site for agriculture, has become increasingly parched and dry. Where a variety of crops and grasses once filled the fields, today there are wide cracks in the soil and growing sand dunes more reminiscent of the Sahara Desert than Central Europe. The region, known as the Homokhátság, has been described by some studies as semiarid — a distinction more common in parts of Africa, the American Southwest or Australian Outback — and is characterized by very little rain, dried-out wells and a water table plunging ever deeper underground. In a 2017 paper in European Countryside, a scientific journal, researchers cited “the combined effect of climatic changes, improper land use and inappropriate environmental management” as causes for the Homokhátság's aridification, a phenomenon the paper called unique in this part of the continent.Fields that in previous centuries would be regularly flooded by the Danube and Tisza Rivers have, through a combination of climate change-related droughts and poor water retention practices, become nearly unsuitable for crops and wildlife. Now a group of farmers and other volunteers, led by Nagyapáti, are trying to save the region and their lands from total desiccation using a resource for which Hungary is famous: thermal water. “I was thinking about what could be done, how could we bring the water back or somehow create water in the landscape," Nagyapáti told The Associated Press. "There was a point when I felt that enough is enough. We really have to put an end to this. And that's where we started our project to flood some areas to keep the water in the plain.”Along with the group of volunteer “water guardians,” Nagyapáti began negotiating with authorities and a local thermal spa last year, hoping to redirect the spa's overflow water — which would usually pour unused into a canal — onto their lands. The thermal water is drawn from very deep underground. Mimicking natural flooding According to the water guardians' plan, the water, cooled and purified, would be used to flood a 2½-hectare (6-acre) low-lying field — a way of mimicking the natural cycle of flooding that channelizing the rivers had ended.“When the flooding is complete and the water recedes, there will be 2½ hectares of water surface in this area," Nagyapáti said. "This will be quite a shocking sight in our dry region.”A 2024 study by Hungary’s Eötvös Loránd University showed that unusually dry layers of surface-level air in the region had prevented any arriving storm fronts from producing precipitation. Instead, the fronts would pass through without rain, and result in high winds that dried out the topsoil even further. Creation of a microclimate The water guardians hoped that by artificially flooding certain areas, they wouldn't only raise the groundwater level but also create a microclimate through surface evaporation that could increase humidity, reduce temperatures and dust and have a positive impact on nearby vegetation. Tamás Tóth, a meteorologist in Hungary, said that because of the potential impact such wetlands can have on the surrounding climate, water retention “is simply the key issue in the coming years and for generations to come, because climate change does not seem to stop.”"The atmosphere continues to warm up, and with it the distribution of precipitation, both seasonal and annual, has become very hectic, and is expected to become even more hectic in the future,” he said. Following another hot, dry summer this year, the water guardians blocked a series of sluices along a canal, and the repurposed water from the spa began slowly gathering in the low-lying field. After a couple of months, the field had nearly been filled. Standing beside the area in early December, Nagyapáti said that the shallow marsh that had formed "may seem very small to look at it, but it brings us immense happiness here in the desert.”He said the added water will have a “huge impact” within a roughly 4-kilometer (2½-mile) radius, "not only on the vegetation, but also on the water balance of the soil. We hope that the groundwater level will also rise.”Persistent droughts in the Great Hungarian Plain have threatened desertification, a process where vegetation recedes because of high heat and low rainfall. Weather-damaged crops have dealt significant blows to the country’s overall gross domestic product, prompting Prime Minister Viktor Orbán to announce this year the creation of a “drought task force” to deal with the problem.After the water guardians' first attempt to mitigate the growing problem in their area, they said they experienced noticeable improvements in the groundwater level, as well as an increase of flora and fauna near the flood site. The group, which has grown to more than 30 volunteers, would like to expand the project to include another flooded field, and hopes their efforts could inspire similar action by others to conserve the most precious resource. “This initiative can serve as an example for everyone, we need more and more efforts like this," Nagyapáti said. "We retained water from the spa, but retaining any kind of water, whether in a village or a town, is a tremendous opportunity for water replenishment.”The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.org.Copyright 2025 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.Photos You Should See – December 2025

The Water Came From Nowhere': Settlements, Hotels and Farms Flooded in Kenya’s Rift Valley

Dickson Ngome's farm at Lake Naivasha in Kenya's Rift Valley has been submerged due to rising water levels

NAIVASHA, Kenya (AP) — When Dickson Ngome first leased his farm at Lake Naivasha in Kenya’s Rift Valley in 2008, it was over 2 kilometers (1.2 miles) from shore. The farm was on 1.5 acres (0.6 hectares) of fertile land where he grew vegetables to sell at local markets.At the time, the lake was receding and people were worried that it might dry up altogether. But since 2011, the shore has crept ever closer. The rains started early this year, in September, and didn't let up for months.One morning in late October, Ngome and his family woke up to find their home and farm inside the lake. The lake levels had risen overnight and about a foot of water covered everything.“It seemed as if the lake was far from our homes,” Ngome’s wife, Rose Wafula, told The Associated Press. “And then one night we were shocked to find our houses flooded. The water came from nowhere.” Climate change caused increased rains, scientists say The couple and their four children have had to leave home and are camping out on the first floor of an abandoned school nearby.Some 5,000 people were displaced by the rise in Lake Naivasha’s levels this year. Some scientists attribute the higher levels to increased rains caused by climate change, although there may be other factors causing the lake’s steady rise over the past decade.The lake is a tourism hot spot and surrounded by farms, mostly growing flowers, which have gradually been disappearing into the water as the lake levels rise.Rising levels have not been isolated to Naivasha: Kenya’s Lake Baringo, Lake Nakuru and Lake Turkana — all in the Rift Valley — have been steadily rising for 15 years. “The lakes have risen almost beyond the highest level they have ever reached,” said Simon Onywere, who teaches environmental planning at Kenyatta University in Kenya’s capital Nairobi. Rising lake levels displaced tens of thousands A study in the Journal of Hydrology last year found that lake areas in East Africa increased by 71,822 square kilometers (27,730 square miles) between 2011 and 2023. That affects a lot of people: By 2021, more than 75,000 households had been displaced across the Rift Valley, according to a study commissioned that year by the Kenyan Environment Ministry and the United Nations Development Program.In Baringo, the submerged buildings that made headlines in 2020 and 2021 are still underwater.“In Lake Baringo, the water rose almost 14 meters,” Onywere said. “Everything went under, completely under. Buildings will never be seen again, like the Block Hotels of Lake Baringo.” Flower farms taking a beating Lake Naivasha has risen steadily too, “engulfing three quarters of some flower farms,” Onywere said.Horticulture is a major economic sector in Kenya, generating just over a billion U.S. dollars in revenue in 2024 and providing 40% of the volume of roses sold in the European Union, according to Kenya’s Ministry of Foreign Affairs.Significant research has gone into the reasons behind the rising lakes phenomenon: A 2021 study on the rise of Kenya’s Rift Valley lakes was coauthored by Kenyan meteorologist Richard Muita, who is now acting assistant director of the Kenya Meteorological Department.“There are researchers who come up with drivers that are geological, others with reasons like planetary factors,” Muita said. “The Kenya Meteorological Department found that the water level rises are associated with rainfall patterns and temperature changes. When the rains are plentiful, it aligns with the increase in the levels of the Rift Valley lake waters.”Sedimentation is also a factor. “From the research I have read, there’s a lot of sediment, especially from agricultural related activities, that flows into these lakes,” says Muita. ‘A mess’ made by the government years ago Naivasha’s official high water mark was demarcated at 1,892.8 meters (6,210 feet) above sea level by the Riparian Association in 1906, and is still used by surveyors today. That means this year’s flooding was still almost a meter (3 feet) below the high mark.It also means that the community of Kihoto on Lake Naivasha where the Ngomes lived lies on riparian land — land that falls below the high water mark, and can only be owned by the government.“It’s a mess established by the government … towards the late 1960s,” said Silas Wanjala, general manager of the Lake Naivasha Riparian Association, which was founded some 120 years ago and has been keeping meticulous records of the lake’s water levels since.Back then, a farmer was given a “temporary agricultural lease” on Kihoto, said Wanjala. When it later flooded and the farmer packed up and left, the farmworkers stayed on the land and later applied for subdivisions, which were approved. In the 60-odd years since, a whole settlement has grown on land that is officially not for lease or sale. This also isn’t the first time it’s been flooded, said Wanjala. It's just very rare that the water comes up this high. That’s little consolation for the people who have been displaced by this year’s floods and now cannot go home without risking confrontations with hippopotamuses.To support those people, the county is focusing its efforts on where the need is greatest.“We are tackling this as an emergency," says Joyce Ncece, chief officer for disaster management in Nakuru County, which oversees Lake Naivasha. “The county government has provided trucks to help families relocate. We have been helping to pay rent for those who lack the finances.”Scientists like Onywere and Muita are hoping for longer-term solutions. “Could we have predicted this so that we could have done better infrastructure in less risk-prone areas?” Onywere said.Muita wants to see a more concerted global effort to combat climate change, as well as local, nature-based solutions centered on Indigenous knowledge, such as “conservation agriculture, where there is very limited disturbance of the land,” to reduce sedimentation of the lakes.But all of this is of little help to Ngome and Wafula, who are still living at the school with their children. As the rest of the world looks forward to the holidays and new year, their future is uncertain. Lake Naivasha’s continuous rise over the past 15 years does not bode well: They have no idea when, or if, their farm will ever be back on dry land. The Associated Press receives financial support for global health and development coverage in Africa from the Gates Foundation. The AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.org.Copyright 2025 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.Photos You Should See – December 2025

A damaged King County levee awaited fixes for years. Then it failed

As an atmospheric river slammed into the Pacific Northwest, water burst through a damaged levee in Washington.

As rainfall inundated the Pacific Northwest this month, swelling the region’s rivers to record levels, the Desimone levee seemed destined to fail.Severe flooding in 2020 had damaged the 2.2-mile earthen barrier near Tukwila. Muddy waters from the Green River bubbled up on the opposite side and seeped into nearby properties. A King County report months later described the levee’s weakened state as the “most important issue” on the river’s lower reach.The years that followed were filled with red tape and bureaucratic infighting among the agencies most responsible for the region’s levee system: King County, its flood control district and the U.S. Army Corps of Engineers. All the while, cities in the flood plain clamored for help, and the Desimone awaited repair.Construction was set to begin this summer, but the Corps pulled out of the work in January, revoking promised federal funding and setting the project back years, according to interviews and public records obtained by The Seattle Times.Reagan Dunn, chair of the district’s advisory committee and a Metropolitan King County Council member, described a pattern of “tension” between the flood control district and the Corps.This month’s back-to-back atmospheric rivers pushed the levee system like never before. The Desimone was the first of two to fail.Earlier in the series of storms, water had once again begun to seep through Desimone’s earthen barrier, which shields a mostly commercial and industrial hub in Tukwila. On Monday, the river tore its way through, sparking a widespread evacuation. Officials feared the ensuing flash flood might be deadly. Workers plugged the hole quickly. Knowing the levee’s risk, they had already been watching the site for days. No injuries were reported in the breach.The patchwork nature of repairs at Desimone, and levees like it, illuminates the growing challenge of protecting Western Washington communities from flooding worsened by climate change.For generations, Washington has relied on levees as a simple solution to a complex problem, said Alan Hamlet, a former Seattle resident and scientist who now works as an associate professor of civil and environmental engineering at the University of Notre Dame. Explosive growth behind them has combined with an overarching desire to spend the minimum required for flood protection, he said. That often means deferring costlier long-term maintenance, mitigation and upgrades of these emergency barriers in favor of more pressing needs. This has resulted in higher risks for the very communities the levees were designed to protect.The state, and much of the country, stands at the nexus of that growth behind the walls of inadequate infrastructure to keep natural disasters at bay, Hamlet said.“Put all those things together and you have a hidden crisis that is going to begin to express itself more and more frequently,” Hamlet said.The 18-year-old King County Flood Control District shuffles its priority levees based on disrepair that changes with the weather. The district has started to plan for the long term, but in its earliest years, it focused on inexpensive and easy fixes in high-risk areas, Dunn said.“In other words, low-hanging fruit,” he said.Flooding in Washington state 2025Bureaucratic tangleThe Desimone levee has been damaged and repaired multiple times over the past six decades. Most recently, years of disagreements among agencies dragged out Desimone’s renovation.The flood control district asked the Corps to step in not long after the 2020 flood. High waters in the Green River then had not only left water seeping through the levee in at least three places, but also bubbling up from underneath.Federal officials agreed to spearhead a plan to repair the levee and cover 80% of the cost. It proposed estimates up to $16.6 million for a project focused solely on restoring the levee to its preflood condition, records show.Such is frequently the case for levee systems nationwide, Hamlet said. Restoring them to their original condition is typically less expensive and complicated. Expanding them or exploring other options takes more time, money and political will.But the flood district wanted more for Desimone: a design that would fix the damage and relieve water pressure further by setting the levee back, restoring some of the river’s natural bank. It was projected to cost the district about $30 million.The district’s plan would take longer and cost more but reduce long-term risks, said Michelle Clark, the district’s director. “We want to do a bigger project so that we’re not coming back to do more repairs.”The flood control district handles planning, but the project hinged on King County finding land along the river for the new work, records show. But it fell short.These types of repairs are more complicated than they might seem, Hamlet said. Strengthen a levee in one place, and you’ll send floodwaters careening into another. Set a levee back from the river, or remove one to restore a flood plain, and first you have to clear out any homes or businesses already there. These structures aren’t the only way to hold back floodwaters, but in many places, they’re the system that’s already there.A failed dealThe Corps worked in fits and starts, at one point in 2022 halting its involvement due to staffing challenges. Even when the county made headway securing land, the Corps said it had used the wrong language in the agreements. At the same time, the county accused the Corps of clerical errors that dragged out the planning process, according to county records.The county — officials for which said they were unable to immediately comment, citing the ongoing flood emergency — was confident it could secure the land, just not on schedule, according to a county brief from April. It proposed breaking ground in 2026 instead.Citing the county’s “inability” to provide the needed land along the highly developed and industrial area, the Corps backed out of the agreement in a January letter.“We have been pushing them since 2020,” Clark said. “And it’s frustrating.”The Corps “worked diligently with King County” but couldn’t move forward without land for construction, the agency wrote in an email to The Times. Levee rehabilitation can be “complex,” it added. “The federal process, sponsor timelines and real estate actions do not always align well, but we are committed to finding a solution when possible,” the agency wrote.Abandoned by the Corps, the county and its partner cities faced their biggest setback, Clark said.Everybody blamed each other as the flood season approached.Concerns heightened after the Corps pulled its support. In July, city leaders from Tukwila, Kent and Renton asked the flood district to more immediately prioritize the levee repair project.Tukwila officials declined to comment, and Kent and Renton officials did not respond to a request for comment by publication time.As the fall rains approached — and without significant improvements on the levee — officials from Tukwila, Kent, King County and the Corps of Engineers spoke in late October to review the contingency plan in case the structure failed, according to Tukwila city records. They walked the levee bank to flag logistical challenges and clarified roles and responsibilities in case of an emergency.The Corps passed along its nearly complete project design for the Desimone levee, according to its January letter to the district. But without the federal government to offset the cost, the county’s grand plan was too pricey. The district has years of research and $25 million set aside for the levee repairs, but it might not be enough, Clark said; it needs to prepare options before it can move forward with a plan.The King County Flood Control District is now, in many ways, exactly where it was in 2020: waiting for the water to recede, preparing to assess the damage and on the verge of once again planning how to fix the Desimone.--Conrad Swanson and Lulu Ramadan© 2025 The Seattle Times. Visit www.seattletimes.com. Distributed by Tribune Content Agency, LLC.

UK’s largest proposed datacentre ‘understating planned water use’

Analysis suggests consumption at Northumberland site could be 50 times higher than US operator QTS estimatesThe UK’s largest proposed datacentre is understating the scale of its planned water use, according to an analysis.The first phase of construction for the hyperscale campus in Cambois in Northumberland has been given the go-ahead by the local council. The US operator QTS, which is developing the site, has promoted its “water-free” cooling system as proof of its sustainability. Continue reading...

The UK’s largest proposed datacentre is understating the scale of its planned water use, according to an analysis.The first phase of construction for the hyperscale campus in Cambois in Northumberland has been given the go-ahead by the local council. The US operator QTS, which is developing the site, has promoted its “water-free” cooling system as proof of its sustainability.But research published this week calls that claim into question. A study of the power and water footprints of AI production by the data scientist Alex de Vries-Gao highlights the underestimated scale of indirect, or embedded, water consumption caused by datacentre operations.QTS estimates the two initial data halls will consume 2.3m litres of water annually, according to documents it submitted to Northumberland county council. Yet applying De Vries-Gao’s methodology to the electricity generation required for the site’s AI servers produces a figure more than 50 times higher, at 124m litres a year, according to analysis by Watershed Investigations and the Guardian.When all the 10 planned halls are operational, the Cambois campus could indirectly consume about 621m litres annually – equivalent to the average yearly use of more than 11,000 people.The company uses a closed-loop system, which typically reuses the same water repeatedly for cooling, but uses more energy to chill the machines. QTS says there will be no pressure on water supply for people in the north-east fromits direct datacentre operations.In a statement, QTS said: “Our power is typically carbon neutral and comes from a range of sources including wind, hydro, nuclear, tidal, etc. QTS does not control the quantity of any water utilised in the power generation process.”But according to De Vries-Gao, datacentre operators must acknowledge the water footprint linked to their massive energy demands, in the same way that power-intensive industries are held accountable for the carbon emissions generated by their electricity consumption.De Vries-Gao said: “The datacentre operator will be responsible for creating the power demand which leads to the consumption of this water. For the same reason, the greenhouse gas protocol already mandates disclosure of indirect emissions related to electricity consumption.”Another potentially understated problem is the air pollution from the datacentre from increased power generation and potential greater use of diesel generators than stated.In the US, researchers and environmental groups have sounded the alarm about worsening air quality as a result of growing emissions of fine particulate matter and nitrogen oxides (NOx) from the power plants and backup generators datacentres rely on. Increased emissions are a result of surging power demand to produce AI systems, according to a recent study. According to Shaolei Ren of the University of California, one of the study’s authors, the evidence connecting datacentre growth to harmful health outcomes from air pollution is already “very strong”.“What is missing is awareness and precise quantitative accounting. The critical gap is that we still do not know, in a transparent and systematic way, how much criteria air pollution data centres actually contribute at the local and regional levels,” Ren said.Common pollutants include ozone, fine particulate matter, carbon monoxide, sulfur dioxide, nitrogen dioxide and lead, which damage human health and the wider environment.This pollution is not only the result of electricity generation from the grid. A proportion often comes from highly-polluting diesel generators, installed to ensure the nearly constant “uptime” demanded by the datacentre and AI industry.Once complete, the Cambois campus will rely on nearly 600 diesel generators for “backup” power – up to 58 per data hall. QTS estimates that regular testing of the system would mean running each generator for five hours a year.The generators have been designated as a backup power system to be used in emergencies if the grid fails. But in Virginia’s “datacentre alley”, a hub where QTS has a datacentre, regulators are considering expanding diesel generator use for planned outages, while environmentalists have warned of pressure to permit generators during grid stress.Julie Bolthouse from the Piedmont Environmental Council, a conservation organisation, said: “They are incrementally increasing under what circumstances they can run and de facto how frequently and how long they can run the thousands of generators we have permitted here in Virginia. Once the generators are in place it is only a matter of time before they use them.”The potential impact of this scenario playing out in Cambois could have negative effects on the local community’s health. Cambois primary school’s playground has been identified by QTS as directly affected by emissions from the generators.In a statement, QTS said: “Generators can occasionally be utilised on a temporary basis to bridge power needs while permanent connections are finalised, but the primary use of generators is for emergency backup purposes.“Diesel generators are not the main source of power for our datacentres. Generators are tested once a month for a short period of time for routine maintenance. Each data centre has a publicly available emissions limit and our normal operations are designed to stay well within those requirements. In the highly unlikely event of a complete grid outage in the UK, backup generators would run only for the duration of such grid outage and at reduced power. Regarding Virginia, QTS has zero control over our competitors.”

These giant sea reptiles lived in freshwater rivers, too

Scientists thought mosasaurs - giant sea reptiles - lived in oceans. But the discovery of fossils in North Dakota shows they may also have lived in freshwater. The post These giant sea reptiles lived in freshwater rivers, too first appeared on EarthSky.

Watch Melanie During of Vrije University in the Netherlands talk about mosasaurs in the late Cretaceous. Researchers found a tooth from a mosasaur in North Dakota that dates back 66 million years. The find suggests these giant sea reptiles lived in freshwater as well as oceans. Video via Genuine Rockstars (Dennis Voeten and Melanie During). EarthSky’s 2026 lunar calendar is available now. Get yours today! Makes a great gift. Mosasaurs were the apex predators of the sea during the late Cretaceous, 94 to 66 million years ago. But they also lived in freshwater habitats, such as rivers, according to a new study. Environmental changes during the late Cretaceous may have driven mosasaurs to adapt to freshwater areas in North America’s inland sea. Chemical analysis of a mosasaur tooth reveals a surprise Mosasaurs were giant aquatic reptiles that lived 94 to 66 million years ago. While T. rex was the dominant predator on land, mosasaurs were the apex predators of the sea. But scientists from Uppsala University in the Netherlands said on December 12, 2025, that they have new evidence showing mosasaurs also lived in freshwater, in inland rivers. Their diverse habitats suggest they were adapting to a changing environment. In 2022, researchers found a mosasaur tooth at an unexpected location in North Dakota. They recovered it from ancient river deposits alongside a T. rex tooth and the jawbone of a freshwater crocodile-like (or crocodilian) reptile. Plus, the area was known for its fossilized Edmontosaurus duck-billed dinosaurs. How did a seagoing mosasaur’s tooth end up in a freshwater river? In this new study, scientists found answers in the mosasaur’s tooth enamel. A chemical analysis of certain elements revealed that this mosasaur had, in fact, lived in freshwater, not salt water. The researchers published their study in the peer-reviewed journal BMC Zoology on December 12, 2025. Artist’s concept of a mosasaur in a river, having just caught a crocodilian. In this new study, scientists suggest that late Cretaceous mosasaurs could have lived in freshwater. Image via Christopher DiPiazza/ Uppsala University. These giant sea reptiles were apex water predators Mosasaurs were large swimming reptiles of the late Cretaceous, 94 to 66 million years ago. Scientists have found most of their fossils in marine deposits, therefore associating mosasaurs as sea creatures. Along with most dinosaurs, mosasaurs perished 66 million years ago, during the K-Pg extinction event. That’s when a massive asteroid crashed into our planet, causing the extinction of many species. Scientists think the tooth they studied came from a mosasaur of the genus Prognathodon. These creatures had bulky heads with sturdy jaws and teeth. The tooth was about 1.2 inches (30 mm) long. Therefore, based on what they knew about other, more complete mosasaur fossils, the researchers extrapolated the size of this individual to 36 feet (11 meters) in length. That’s about the size of a bus. Per Ahlberg, of Uppsala University in Sweden, is a paper co-author. He said: The size means that the animal would rival the largest killer whales, making it an extraordinary predator to encounter in riverine environments not previously associated with such giant marine reptiles. On the left, different views of the mosasaur tooth. On the right, an image of the T. rex tooth in the ground. The red rectangle shows the location where the mosasaur tooth was recovered. Image via During, M. A. D., et al./ BMC Zoology (CC BY 4.0). Probing the tooth enamel with isotope analysis For some elements, an atom has the same number of protons but a different number of neutrons. These different forms of an element are called isotopes. For example, carbon-12, carbon-13 and carbon-14 are three carbon isotopes. They all have six protons. But they also have six, seven and eight neutrons, respectively. The ratio of isotopes for an element can vary depending on the type of environment. In this study, the scientists looked at three elements: oxygen, strontium and carbon. They found there was more oxygen-16 in their mosasaur’s tooth enamel compared to mosasaurs found in marine environments. Therefore, they concluded, this animal lived in freshwater. Strontium isotope ratios also suggested the same. Melanie During of Vrije University in The Netherlands is the paper’s lead author. She said this about carbon isotope ratios they found: Carbon isotopes in teeth generally reflect what the animal ate. Many mosasaurs have low carbon-13 values because they dive deep. The mosasaur tooth found with the T. rex tooth, on the other hand, has a higher carbon-13 value than all known mosasaurs, dinosaurs and crocodiles, suggesting that it did not dive deep and may sometimes have fed on drowned dinosaurs. The isotope signatures indicated that this mosasaur had inhabited this freshwater riverine environment. When we looked at two additional mosasaur teeth found at nearby, slightly older, sites in North Dakota, we saw similar freshwater signatures. These analyses shows that mosasaurs lived in riverine environments in the final million years before going extinct. Melanie During prepares a sample of the mosasaur tooth for strontium isotope analysis. Via Melanie During/ Uppsala University. An ancient sea in North America During the late Cretaceous, an inland sea divided North America, separating the east and west sides of the continent. This sea is known as the Western Interior Seaway. The amount of freshwater entering this sea increased over time. As a result, the seawater gradually transformed from salt water to brackish water, and then to mostly fresh water. The scientists think that this created a halocline. In other words, salt water – which is heavier because of dissolved salts – formed a layer at the bottom of the sea. Meanwhile, the lighter freshwater sat on top of it. These giant sea reptiles might have lived in freshwater Ahlberg commented that their isotope analysis confirms the theory about halocline conditions in the Western Interior Seaway: For comparison with the mosasaur teeth, we also measured fossils from other marine animals and found a clear difference. All gill-breathing animals had isotope signatures linking them to brackish or salty water, while all lung-breathing animals lacked such signatures. This shows that mosasaurs, which needed to come to the surface to breathe, inhabited the upper freshwater layer and not the lower layer where the water was more saline. Late Cretaceous mosasaurs may have adapted to the changing salinity of the inland sea. During said: Unlike the complex adaptation required to move from freshwater to marine habitats, the reverse adaptation is generally simpler. The scientists cited modern examples of these adaptations. For instance, river dolphins live in freshwater but they’re descended from marine ancestors. The saltwater crocodile in Australia is able to move between freshwater rivers and the sea. Bottom line: Scientists used to think that mosasaurs were exclusively sea-dwellers. But new research suggests that North American late Cretaceous mosasaurs might have lived in freshwater. Source: “King of the Riverside”, a multi-proxy approach offers a new perspective on mosasaurs before their extinction Via Uppsala University Read more: Nanotyrannus, a T. rex mini-me, coexisted with the big guysThe post These giant sea reptiles lived in freshwater rivers, too first appeared on EarthSky.

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