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The toxic legacy of WWII shipwrecks

November 15, 2024

Thousands of ships loaded with oil were sunk during the fierce sea battles of the Second World War. That means they’ve been sitting underwater for eight decades, with no maintenance or protection. Scientists fear many of these wrecks are now close to collapse — and that a spike in catastrophic oil spills may be on the horizon.

https://p.dw.com/p/4mymo

Interviewees:

Dr. Matt Carter – maritime archaeologist and research director for the Major Projects Foundation

Dr. James Delgado - maritime archaeologist and senior vice president of archaeology firm SEARCH, Inc.

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Transcript: 

Matt Carter: It's picture postcard - palm trees, sand… There's this beautiful clear blue water, nice and warm, quite a lot of fish life.

And as you kind of descend down, it gets a little bit darker, a little bit darker and as you come down and then there's an enormous shipwreck kind of comes out of the gloom

The Fujisan Maru.

A massive Japanese oil tanker that was bombed by US aircraft in February 1944.

Matt: It's quite a sight to see.

It's just a huge, huge kind of steel object. It's enormous. It's 150 odd metres long, over 9000 tonnes…

It’s sitting on the sea floor - about 60 meters down - in an idyllic atoll in the Pacific Ocean. A place called Chuuk Lagoon… part of the island nation of Micronesia.

SFX American news reel about Operation Hailstone

The Fujisan Maru was sunk during a surprise US attack called "Operation Hailstone."

Japanese forces used Chuuk Lagoon as a major naval base during World War II, and they suffered big losses during the attack.

There are more than 40 large Japanese shipwrecks like the Fujisan Maru in this lagoon, all sunk by U.S. forces. It’s become a kind of underwater ship graveyard.

Matt Carter is a marine archaeologist. And for the last several years, he’s been going on dives to investigate these wartime relics in this part of the Pacific. In the case of the Fujisan…

Matt: It had several bombs dropped on it. And when it hit the bottom, the front sections crumpled. You can still see the bridge where the windows were. There's still the little ladders that people climbed up and down.

Matt loves history, he loves shipwrecks, and he loves diving. But there’s a different reason he’s interested in the Fujisan:

Matt: It was an oil tanker…So when it sank, it was actually holding potentially quite a large volume of oil.

Matt says archive documents suggest it could have had almost 800,000 gallons on board. No small amount. But there’s some crucial information missing:

Matt: We don't know how much of that is still in the wreck today. How much of that has actually gone? Is it all of it? Unlikely. Is it half? Is it 40%?

Chuuk Lagoon in Micronesia has one of the biggest concentrations of wartime wrecks in the world. Wrecks that may well still be holding toxic cargos of oil, chemicals, and unexploded munitions. And that matters, because by now, they’ve been sitting in their underwater resting places for more than 80 years.

Matt: … we do know that they are corroding. Rust doesn't sleep. They do have a shelf life, these shipwrecks

Scientists warn that these ships are weakening, their hulls getting thinner and more likely to collapse, which could trigger large oil spills.

Matt: The people of Micronesia, you know, they are so vulnerable to this kind of disaster. So it's really quite a terrible thing that's waiting out there.

James Delgado: And now what we're facing is in some cases catastrophic releases of oil and there’ve been some that have clearly created a problem, not just in terms of the environment, but devastating fisheries for communities.

This problem isn’t limited to the Asia Pacific region.

It’s global. From the Baltic Sea, to the Atlantic Ocean, to the US Pacific Coast.

There are millions of sunken ships littering the world’s oceans. The International Union for the Conservation of Nature says more than 8,000 of them are potentially polluting wrecks – mostly from the two world wars. 

James: The big picture is scary... When you consider that of all the shipwrecks around the world that are out there and potentially are, as the phrase has been said, ‘slicking time bombs.’ Then you begin to really understand that when you look at the larger picture, there's a problem that has to be dealt with.

So what is being done about these wrecks? That’s coming up on Living Planet. My name is Neil King.

The International Union for the Conservation of Nature warns that over 8,000 WWII shipwrecks may still hold large amounts of oil—possibly up to 6 billion gallons. To give you an idea, that total is 500 times the amount of oil released in the Exxon Valdez spill in 1989.

That’s just an estimate. Because scientists don’t actually know for sure how much oil is still on board all of these ships. Or even what state they’re in.

Are they still intact? Or were they blown to shreds when they sank?

Answering these questions is crucial to finding out whether a ship could cause a spill. But getting those answers? Well turns out it’s often not so straightforward.  

Still, maritime authorities and researchers in different parts of the world are gradually working to map these wrecks before it’s too late.

In the US, the agency that’s focused on this is the National Oceanic and Atmospheric Administration. It believes that there are more than 80 shipwrecks in US waters that could pose an oil threat. But there’s the slight hitch that around half of them haven’t even been found yet.

Like the Gulfstate – an oil tanker that went down somewhere off the Florida Keys in 1943. No one knows exactly where it is. But what they do know: it likely sank with around 85,000 barrels of oil on board. By the way one barrel is equal to 42 gallons. So in this instance that’s about three and a half million gallons of oil we’re talking about.

Another ship on the agency’s list: the USS Coast Trader.

SFX from Nautilus survey of Coast Trader

On June 7, 1942, the merchant vessel Coast Trader was carrying newsprint and 8,000 barrels of heavy fuel oil when it was hit by a Japanese torpedo off the US West Coast.

James: There was oil released, but how much we didn't know, and we didn't exactly know where the ship was.

The torpedo blasted a huge hole in the ship’s side, sending rolls of newsprint fluttering through the air. The 56 people on board managed to escape on lifeboats. And after 40 minutes, the Coast Trader had vanished below the surface, coming to rest around 150 meters below, on the sea floor.

SFX Nautilus survey

What you’re hearing is audio from a survey team … looking at what they believe to be the long lost wreck. It’s 2016, and this is the first time anyone has actually laid eyes on the ship since it sank.

James: When we find a shipwreck, and the robot or you're diving down and looking at it yourself in scuba, when you see that. Whether you're the first to set eyes on it or not, there still is that sense of entering a space that very few go into, if ever.

James Delgado, a maritime archaeologist, led the survey team. Over his 40-year career, he’s explored more than 100 shipwrecks, including the Titanic.

James: And for you, at least as the observer, as the archaeologist,  it truly is a new experience. For me, it's almost as if I picked up a book. And I'm about to read it, and I'm going to learn many things that I never knew before.

SFX Nautilus survey

Footage recorded by underwater robotic vehicles is beamed back to a big control center on the mainland via satellite.

James: Just as, you know, in space launches.

The team watches the algae-covered wreck slowly reveal itself in the semi-darkness… Fish dart around the structure, and there are white billowing anemones clinging to the hull.

James: What we saw was the last two holds with about half of the oil had been breached by a very powerful torpedo explosion. Probably more than one.

SFX Nautilus survey

James: You could see where the torpedo had hit - this massive wound in the side of the ship. The plating pushed back, peeled away, jagged edged, and collapsed beams from the decks, the frames as the ribs of the hull and the twisted plating. Moving back to where we could see what was left of the stern post where the rudder was hanging, and then the toppled platform with the deck gun still there.

Towards the front of the ship, the hull was more intact…

James: And you could see in the superstructure portholes where cabins and the radio room and all of that was…

The hatches were open, the masts had fallen, but you could still make out the gear and the winches for raising and lowering the cargo.

All these details are being taken in to ultimately draw conclusions about the ship’s threat.

James: So that deductive process is much like a coroner finding an unidentified corpse in an alley.

We use many of the same techniques underwater, and then in this case looking at it and saying: that tank's gone. That tank's gone. That's what they carried and it's a full load. So that much oil came out in 1942. This much oil is left.

After putting eyes on the ship, the team could see that some of it had deteriorated. But otherwise the hull was in reasonably good shape. They concluded that Coast Trader likely still had half its oil inside, but they couldn’t see any sign of a leak….

James: There was no slick, nothing coming out, nothing bubbling, and the hull itself was so solid and intact…

… and that the chances of the ship collapsing in the near future would be slim.

But James says that’s not the case for many of the other ships he’s investigated. Some of them have been leaking oil for years.

Matt Carter, who we heard from at the start of the show, has seen it in the Pacific too:

Matt: And you'll be travelling … to one of the dive sites and you'll go through an oil slick like on most days you're there.

Matt works with the Major Projects Foundation. It’s a non-profit focused on marine research and conservation, and they’ve just finished surveying all the Japanese wrecks in Chuuk Lagoon. This is the first time it’s been done, and it’s part of a project that’s funded by the Australian government.

Right at the start, to get an idea about what a ship might have been carrying, they begin with desk work and archive research…

Matt: One of our historians actually taught himself to read Japanese so he could read the Japanese archives.

They also use satellite data to track any oil on the ocean surface, as well as multi-beam sonar to map a wreck, before they go diving at the site for a closer look. The aim is to work out which ones might cause a catastrophic spill.

Matt says three-quarters of the ships they’ve flagged as being a potential pollution risk are already leaking oil every day. He remembers seeing little black oil bubbles escaping from a hole on a Japanese ship called the Heian Maru.

Matt: And we've just done quite a long dive mapping it. We had to stay at six metres … before we could come up to avoid getting the bends, getting decompression sickness.

And so we're on the top of the ship and we're quite close to this little stream of bubbles. And we were there for half an hour and the little bubbles just were coming up the whole time. And I was trying to calculate if they're coming up this fast, and you take that back 80 years, you know, how much oil has already come out of the ship? It was this kind of surreal moment of just watching it, and knowing it is chronically poisoning that bit of the environment.

We do see impacts where, you know, you are seeing kind of the fish eating these little oil bubbles as they come up because they look like food and that's, you know, it's toxic.

Some of the other wrecks he’s dived to have been full of oil.

Matt: And there's just this enormous kind of, well, void almost, and it's just this black thick oil …it just looks horrible. It's this thick, gluggy…  and you know what it is straight away when you see it. It's just, yeah, very nasty looking stuff…I try and stay away from it as much as possible.

It's right there and it's just one tiny pinhole of corrosion from leaking out into the surrounding environment. So they're this close.

These drip drip bubble leaks are obviously nasty, but Matt’s team is most worried about the prospect of a major spill, which could happen if a ship actually breaks apart or collapses. They’ve done modelling to predict what would happen in Chuuk Lagoon if the Fujisan Maru were to have a spill. Remember, that’s the ship Matt introduced us to at the start of the episode.

Matt: It’s very close to the coast. And in 100% of the models, the oil reaches the land. There's no, no way of avoiding it. If there is a decent enough, large enough slick, it will hit land.

That’s just if one-tenth of the oil estimated to be on board the tanker gets out.

Matt: Even that 10%, if it's released, can do some serious damage to a place like Micronesia, to Chuuk Lagoon, that's so incredibly reliant on the ocean for everything.

In the Asia Pacific region, there are an estimated 3,800 potentially polluting wrecks that were sunk during the Second World War – including more than 300 oil tankers. When they went down, these vessels had up to 1.5 billion gallons of petrochemicals on board.

The Major Projects Foundation, where Matt works, is investigating World War II wrecks off the coasts of Micronesia, the Marshall Islands and the Solomon Islands.

These island states were not party to the war. But Matt says today, they would have the most to lose in the event of a spill. An oil slick could threaten not only wildlife but also food security, tourism and the livelihoods of islanders.

Matt: For Fujisan, for example, if it spills a significant amount, then it will absolutely take out the local fishing industry, the tourism industry and these have massive flow on effects - through to things like not being able to afford school fees for your kids because you can't get the money and that can impact all sorts of different parts of society.

Matt: The ocean is central to everyday life. It's all so connected in the Pacific Ocean that when you have something like an oil spill, it disrupts so much more than kind of, I guess in some of the other, other countries.

After an earthquake in the Solomon Islands two years ago, there was an oil spill thought to come from one of the nearby wrecks… important fishing zones had to be shut down.

Matt: And the local villages couldn't fish for several weeks in that area. So, you know, it does have these impacts, but so far we haven't seen kind of the, I guess the full potential or the full scale of what is predicted to happen. And that's yeah, that is the disruption of… people kind of living their lives, and on a on a pretty major scale.

Scientists estimate shipwrecks corrode at about 1 millimeter a decade – so their hulls are gradually getting thinner overtime. Climate change also isn’t helping the situation.

More frequent and severe storms could speed up the breakdowns of shipwrecks. Warming sea temperatures can increase corrosion. And acidification caused by the oceans absorbing excess carbon dioxide also weakens corals that in some cases are protecting the wrecks.

Here’s Matt again:

Matt: And what I guess we're worried about is this kind of perfect storm situation where you do have something like a typhoon come through, and multiple wrecks get damaged by wave action, they collapse. And then you're in a situation where …on land, you might not have any power, you might not have any running water, any communication. And you've got thousands of litres of oil washing up on your beach as well. So you're getting kind of hammered from everywhere. And that's, that's not an unlikely scenario in a place like Micronesia, which gets hit by typhoons. So that is, you know, it's a worst case scenario, but it could very well happen.

Researchers like Matt stress it is easier and cheaper to take action early. Rather than waiting for oil to wash up on the beach and then having to restore a damaged ecosystem.

Cleaning up pollution from the world’s wrecks - without preemptive action - could cost up to $340 billion by one estimate.

But what does preemptive action even mean? Well, one option is pumping the oil out of the wreck.

That’s what happened with the tanker USS Mississinewa. It was sunk by a Japanese torpedo in Micronesia in 1944, and lay undiscovered for decades. But in 2001, it started leaking oil into the Ulithi lagoon after a storm. 24-thousand gallons of the stuff leached out and started threatening nearby reefs, fisheries and turtle breeding grounds. For a time, all fishing in the lagoon was banned. Then, in 2003, the US paid around $6 million for a major salvage operation to pump 1.8 million gallons of oil out.

The same thing happened with another wartime oil tanker, the British supply ship Coimbra. It was carrying around 75,000 barrels of oil when it was shot by a German U-boat off the coast of Long Island in 1942. But in 2015, the wreck started leaking increasing amounts of oil. So it was pumped out, to avoid a catastrophic spill that would have led to oil washing up along the US east coast.

Matt: Around the US, Norway, Finland. These kind of ships are pumped out quite regularly. So salvage companies, this is this bread and butter for them. They come along, pump out the oil, take it away and dispose of it. Job done. Unfortunately, that comes with a price tag. That's the only real kind of thing stopping this work being done in the Pacific, is the sheer amount of money it costs per shipwreck.

How much exactly? Matt says their estimates for pumping oil off ships in Micronesia range from 5 million to 8 million US dollars a ship.

Matt: In the Pacific, there's just no resourcing for that kind of thing. Any country in the world would struggle with this many pollution sources scattered around the their homes. So to put that on the hands of Chuuk. You know, it would be hundreds of millions of dollars for them to be in a position where they could, yeah, avoid the impacts. And that's, that's just not realistic.

There’s another problem we haven’t mentioned yet. But it is worth talking about. And that is – what then happens to the oil once it’s removed? In the case of the USS Mississinewa, the oil recovered from the wreck was shipped to Singapore to be sold. Matt says that in other cases in the US, the oil has been used in manufacturing processes.

Matt: In the Pacific, there's really strong kind of regulations around hazardous waste and transporting hazardous waste across national boundaries. There's also very few places in the Pacific who are capable of disposing of this oil to environmental standards. The distances involved from getting oil from Micronesia, from Chuuk, to somewhere else are huge. Even getting the ships there is incredibly expensive… The removal of the oil, for a start, is expensive, and then disposing of that oil could be, you know, even more expensive than that.

Which brings us to another key question – who should foot the bill? 

Here’s where it gets even murkier, because this is a cross-border problem.

So whose responsibility is it to clean up a ship that belonged to Japan, but was bombed by the US, and that now lies to rest in waters off Micronesia?

Or a British ship that was hit by a German U-Boat in the Atlantic? Here’s maritime archaeologist James Delgado.

James: I think, ultimately, it will inevitably be the issue for a coastal state. That is, if it's in your waters and it's affecting your fishing, it's going to affect your beaches. Then it becomes your problem to deal with.

It gets more complicated when wrecks lie outside national borders - somewhere in the deep ocean. James says in cases like those, there needs to be a concerted international effort. Some governments are taking action. But James says the issue is increasingly being taken up by not-for-profit groups. And there’s also been growing attention on the plight of communities in the Global South that just don't have the resources to deal with a spill.

James: In places, particularly in the Pacific, where these wrecks have potential for economic harm or environmental harm, where people depend on fishing those reefs and if they're covered with oil and we're not talking about making money, we're talking about putting food on their table. Then it becomes a problem. Do they have the money or the requisite technology in their island nation to deal with that? No. So then it becomes somebody else's responsibility. In the case of a warship, nations never abandon their warships. They have the same legal status as a consulate or an embassy. So with that, if you're going to assert that, then you better clean up your own mess. And that's what the United States has been doing with wrecks like the Mississinewa at Ulithi

Matt says for many years the issue of polluting wrecks and their impact on Pacific islands was ignored. But that's starting to change.

The organization he works for, The Major Projects Foundation, was founded in 2018 and has been leading surveys of wrecks in the Pacific. Groups like the global safety charity Lloyd's Register Foundation and the Ocean Foundation have set up an international coalition that aims to build a global framework by 2028 to assess shipwrecks, share data and intervene to avoid pollution risks. 

In August, the US and Japan put out a statement saying they were planning to explore the possibility of a joint collaboration on removing oil from the sunken ships in Chuuk Lagoon. 

Matt: So it is getting some momentum. We are going in the right direction.

Matt says it may be a complicated problem. But it's one that can definitely be solved. 

Matt: When we look at climate change, we look at sea level rise, now those are challenging problems. As an individual, it's like how, how can I work on that? But with these shipwrecks, it is solvable. It is something where all we need is the right amount of political will and funding that comes with that. And you could take the oil out of the highest risk 5 shipwrecks in Chuuk starting in a couple of weeks’ time. You know, you could methodically do that. And there you go, you've kind of prevented that environmental disaster.

The thing about shipwrecks is, they’re not exactly visible. They’re largely hidden to us land-dwellers. Especially those that are in the deep ocean.

James says he believes this is the main obstacle to tackling problematic wrecks -- a lack of public awareness. 

James: It's not in your neighborhood. It's out to sea. In some cases it's well out to sea, but out of sight, out of mind.

We're not doing enough, as a planet, as a global community, because there's so many of these. And if in the next few years, more of these continue to deteriorate, particularly those in warmer and more shallow waters, we will have massive releases of oil that cumulatively are far worse than Deep Water Horizon or the Exxon Valdez or Amoco Cadiz or many of the other disasters that have become famous.

What made some of those famous, however, was when that oil came ashore and then when the rest of the world suddenly said, wow, this isn't just somewhere out in the ocean, it's right here and it's covering birds and it's destroying a fishery.

Shipwrecks can mean different things, depending on who you ask. But for many people, they probably don't immediately conjure up ideas of environmental catastrophe. 

They're archaeological sites, 

war graves for sailors, 

playgrounds for diving enthusiasts

… or cultural icons that inspire music and films – just look at the Titanic.

Given time, wrecks can also be colonised by sea life – serving as an artificial reef and haven for fish. This shows that, if managed safely, sunken ships could even boost biodiversity rather than poison it.

We'll give the last word to James: 

James: I would just say that, of the millions of shipwrecks that are out there, I think the majority of them date to the last century, particularly with the two world wars.

They represent a variety of things to us all. They're a record of our history. The ocean is our largest graveyard. But it also is a sensitive part of the planet's ecosystem.

The oceans are tied to all life. If we kill the oceans, we kill the planet. So if there's one thing that I learned from shipwrecks a long time ago, is the only way to survive is if you have a lifeboat. And if you don't have a lifeboat, you do everything to keep your ship afloat. This planet does not have lifeboats. So unless we take care of problems like this. We're not going to survive.

This episode was produced by Natalie Muller and edited by me, Neil King. Our sand engineer was Gerd Georgii.

If you have questions, comments or suggestions please do send us a voice message or an email to [email protected]. And while you’re online, we’re always very grateful for any reviews or ratings that you can give us on podcasting platforms such as Apple Podcasts or Spotify. You can also find Living Planet on YouTube, just go to DW Podcasts for that. That’s it. Thank you for listening and sharing Living Planet with friends and family. Living Planet is brought to you by DW in Bonn, Germany.

 

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