ss richard montgomery unexploded bombs
Illustration: Dan Strange

After Beirut, Experts Warn of the 14,000 Unexploded Bombs Off the UK Coast

A WWII shipwreck packed with bombs has loomed over the British seaside town of Sheerness for 76 years. The explosion could be bigger than Beirut – but will it explode? And what happens when it does?

A lord and a professor walked into a room – but this will be a very long punchline.

It was the 28th of March, 2019, at the launch of the Institute of Strategic Risk Management (ISRM), and the room was in Deloitte’s London office. The lord was Lord Toby Harris of Haringey, chair of the ISRM. The professor was Professor David Alexander, a specialist in risk and disaster reduction at University College London. They were telling each other stories about risk and disaster, as you do at these events, when Professor Alexander began to tell one Lord Harris had never heard, related to research he was about to publish.


The story goes like this. In August of 1944, the American Liberty ship SS Richard Montgomery left the Delaware River in Philadelphia, Pennsylvania and sailed to the River Thames Estuary, near the Isle of Sheppey, Kent, around 40 miles east of London. The Liberty ships were massive vessels, built in only 42 days, and designed to carry cargo to support the war effort.

The SS Richard Montgomery carried 6,225 tons of high explosive bombs and detonators. But after arriving in a force-eight gale, it encountered a number of complications, followed by a calamity of errors, and ran aground on a sandbank in shallow waters. On Monday the 25th of September, 1944, a bold salvage operation tried to retrieve the explosive cargo, but this was abandoned when the ship snapped in half and started to submerge.

It has laid there ever since, in 15 metres of water, just 1.5 miles from the seaside town of Sheerness, the biggest settlement on the Isle of Sheppey. Three ominous masts protrude above the water’s surface at all times, a warning of what lies beneath; 13,961 unexploded bombs remain onboard (this figure is contested – other estimates put it at 14,340 or 15,906 bombs), ranging from phosphorus smoke bombs to cluster fragmentation bombs to colossal 2,000lb general purpose bombs. Locals have reported seeing yellow flames dancing on the surface of the water near the wreck, most likely phosphorus leaking out and reacting with the air.


In 1970, the Royal Military College of Science was asked to study the consequences should an event, however unlikely, cause the entire explosive quantity on the SS Richard Montgomery to blow up at once. They concluded that the result would be a 3,000-metre-high column of water and debris, and a five-metre tsunami, which would devastate the region. Some reports suggested this tsunami could travel down the Thames and flood central London.

Just three miles away from the shipwreck, on the Isle of Grain, stands the largest liquid natural gas storage facility in Europe. Each of the three gas storage tanks are bigger than the Royal Albert Hall. The worry is that an explosion on the shipwreck could cause a secondary enormous explosion at the gas facility, similar to when the Great East Japan Earthquake and Tsunami of 2011 caused a secondary disaster at the Fukushima Daiichi Nuclear Power Plant.

We never normally leave bombs alone. The Ministry of Defence deals with around 60 bomb disposals in the UK per year. When a 500 kg World War Two bomb was found near London City Airport in 2018, local residents were evacuated and flights were cancelled for 48 hours, affecting 16,000 passengers. When a 2,000lb World War Two bomb (of which there are possibly thousands on the SS Richard Montgomery) was safely detonated in an incident near the Isle of Wight in May, 2019, it caused a magnitude three earthquake.


But the shipwreck of Sheerness has remained untouched since that abandoned salvage mission many moons ago. It is surveilled 24 hours a day and surrounded by an exclusion zone marked by buoys, but no action has ever been taken to nullify the threat. The situation, it seems, is almost too huge to conceive, and too titanic to risk assess. Annual reports do little other than evidence that cracks in the hull are getting bigger and the structure is slowly deteriorating.

Wild solutions have been proposed – building a Chernobyl-style sarcophagus over it, or a 1,800-metre dam around it – but none have ever come to pass. Instead, consecutive governments have decided to leave it alone, in the hope that the wreck will become harmless. However, nobody can agree on whether this is a grounded belief.

In 1964, The Wide World Magazine interviewed Major A. B. Hartley MBE – a former Royal Engineer and the foremost expert on World War Two bomb disposal at the time – about the issue. "Leaving that ship there," he said, "is like finding a long forgotten bomb dump in a crowded suburb and then walking away from it without bothering even to tell anyone. In my opinion those bombs are a major hazard. They won't make themselves safe. On the contrary, as time passes they may become more dangerous. A lot more dangerous.”

Over the years, this story has become marred by the blurry lines of truth and fiction, riddled with exaggeration and understatement. And yet, after 76 years, the central questions still remain unanswered: could the SS Richard Montgomery explode? And what would happen if it did?


‘This is extraordinary,’ thought Lord Harris, when Professor Alexander finished his story. He endeavoured to raise a debate on the matter in the House of Lords as soon as the schedule would allow.

sheerness blast mural

A mural in Sheerness. Photo: Richard Splash / Alamy Stock Photo

I arrived at Sheerness eight days after the explosion in the port of Beirut – which killed at least 190 and injured around 6,500 – and the front page of the Sheerness Times Guardian read: “SHIP FEARS: BLAST BIGGER THAN BEIRUT”.

Sheerness can’t decide if it’s a post-industrial town or a seaside resort, which makes for a strange mix between Middlesbrough and Margate. Ships from all over the world come to its port to offload foreign cars, meat and fruit, via a busy shipping lane, the Medway Approach Channel, which runs just 200 metres away from the shipwreck. This is one of the main risk scenarios: a collision. During foggy conditions during the summer of 1980, a misguided ship came within 15 metres of the wreck. Later that same week, a Danish tanker carrying fuels was on a collision course but rapidly changed direction just six minutes before it would have made contact.

At one end of the beach there was a glistening rubbish dump stacked 30-feet-high with metal fragments. In a fenced off area were 20 shipping containers marked “Chiquita Bananas”, from which there came a constant low drone of activity: lorries stopping, reversing, the occasional crash of a load of stuff being dumped from a great height. But when I turned and walked in the opposite direction, the beach looked like a Martin Parr photograph. It was the hottest week in decades, the sea was perfectly still and the shingle was filled with sunbathers. A sleeping man floated far away on a yellow lilo, and while staring at him enviously I noticed for the first time the four unmoving black obelisks stuck to the water’s surface, a few kilometres beyond: the masts of SS Richard Montgomery.


On a bench on the sea wall, I sat down to interview Colin Harvey, a local historian, and Ken Rowles, a filmmaker, who has been continuously working on a film about the shipwreck for 12 years. The pair regularly give talks and raise local awareness about the issue. Ken had a soft London accent and his face mask slipped off whenever he spoke. Colin had the smooth articulation of a late night talk show host. He rifled through his bag and handed me a photocopy of the ship’s original manifest.

“I’ve been messaging the local MP recently, because of the Beirut situation,” said Ken, 75. “He said, ‘There's nothing similar about it.’ I said, ‘Well, it's two things that can blow up. That's what’s similar!’”

“What happened in Beirut was different explosive materials, but neglect comes into it. People wouldn't accept it was a problem, then it happened. This is a problem,” said Colin, 76, waving his hand at the sea. “We have a lot of doubting Thomases, don't we, Ken?” Ken nodded. 

Ken told me he’s had warnings in the past from the Ministry of Defence to cancel local meetings about the shipwreck, because they were stoking fear. “But the person never identified themselves, and I wondered if it was the local press trying to make a story,” he said. He also said his unreleased film – A Disaster Waiting to Happen, narrated by Golden Globe-winning actor Ian McShane – was rejected by the BBC because “the government won’t allow it to be broadcast”. Colin said he’s had calls from the MI5.


There’s something slightly conspiratorial about the way they share these stories, and they can occasionally come across as amateur sleuths on the trail of a tasty mystery, but in some ways they are right to have an air of suspicion.

Since the day it sank, the wreck has been shrouded in secrecy and misinformation. For more than a decade after the war, it was classed as a state secret by the UK government, despite the fact it was visible for all to see. Pleasure boats would take Sheerness locals out for 2 shillings and sixpence and let them touch the masts, but nobody could talk about it, because it wasn’t really there. When Colin was a schoolboy he found a yellow glass tube on the beach and put it in his pocket. “That night I showed it to my dad and he nearly had a coronary,” said Colin. “It turned out to be a vial of nitroglycerine, one of the detonating sources for bombs.”

In 1999, the government commissioned BMT Reliability Consultants to do a risk assessment of the wreck, but then suppressed the resulting report. In 2005, the Evening Standard leaked some of it in a news story titled “Tidal Wave Alert Over Warship”. BMT Reliability Consultants, they wrote, had concluded that a mass explosion was possible, one that could swamp coastal communities and cause upwards of £1 billion damage in a 12-mile radius.

Sources told me a copy of the report lurks somewhere in the Houses of Parliament libraries, but one local, Tim Bell, 75, said his attempts to get permission to view it have always encountered bureaucratic hurdles. Another local man, Mike Barker (who received an MBE in 1972 for his services in bomb disposal for the British Army), has tirelessly chased the government with Freedom of Information requests for the best part of 20 years, with mixed success.


The most recent development was that the Ministry of Defence, on behalf of the Department for Transport, put out a tender worth up to £5 million for a salvage company to cut down or reduce the height of the ship’s masts, for fear that they could collapse and trigger an explosion. This marked a drastic U-turn in their previous policy of non-intervention with the wreck, and suggested to Ken and Colin that perhaps the government are privy to information that the general public are not.

“I interviewed Gordon Henderson [the Conservative MP for Sittingbourne and Sheppey] for my film, and he admitted the worst that could happen is a tsunami,” said Ken.

“A tsunami!” laughed Colin. “This place would get levelled. Two-thirds of Sheppey is below sea level, so it would suffer badly. It's only this wall keeping the sea out.”

I wondered if Ken and Colin had become so fascinated by the ship that they may have become guilty of a little scaremongering; the story does seem to attract men of a certain generation, with a keen interest in the wars. But then, people demanding action from those in power, should the worst thing happen, are often viewed as alarmists, until the worst thing actually happens. Like the Grenfell Tower residents group, who, 18 months before the blaze that killed 72 people, warned of conditions that could lead to a tragedy and were sent a cease and desist letter by their local council for “scaremongering”.


“I think when I know they are going to cut the masts down, I’m going to take a holiday,” said Ken. “But I’m going to approach the company that do it, and talk to them. The way I see it, there’s a story there that should go in my film.”

“It's the film that never ends,” said Colin.

ss montgomery explosives

The visible masts of the SS Richard Montgomery wreck. Photo: Jason Richardson / Alamy Stock Photo

The waters around the UK contain a lot of bombs. After WWII, the British government dumped approximately 1.17 million tons of conventional and chemical weapons into the sea. In 1995, the drilling of an undersea gas pipeline between Scotland and Northern Ireland disturbed a large stash of these discarded weapons in an underwater trench known as Beaufort’s Dyke. Within a month, 4,500 bombs had washed up on the west coast of Scotland.

The waters around the Isle of Sheppey are no different. In an interview with Channel Four, one fisherman (whose identity was protected) admitted that they fish up bombs every five to six hours. The protocol in these situations is to call the Ministry of Defence, who send a team to dispose of the device. The fishermen do this when they drag up something big, like a sea mine, but they don’t have time to do it on every occasion. And so it has become a custom to pull the bombs on deck and dump them in the exclusion zone of SS Richard Montgomery. Why? Because nobody can fish there, so they won’t be dragged up again. A shipwreck full of bombs, surrounded by even more bombs.


So do the people of Sheerness live in terror? Not quite. If the COVID-19 pandemic has taught us anything, it’s that human beings cannot stay in a heightened state of anxiety for long, before they eventually normalise or ignore the situation. The ship has become an object of affection and heritage. Locals call it “the Monty” or “old friend”. On the outside wall of the seaside amusement arcade, there was a large mural. It featured a stern-faced mermaid, lying on the beach with her hands on a TNT detonator, a wire running out to sea to the masts of the wreck. “Welcome to Sheerness,” it read, “You’ll have a blast.” A recent survey by risk and disaster researcher, Ane Gundersen, found that love for the ship and anxiety over its threat was basically a 50/50 split.

This is an island crowded with the ghosts of history, and one can understand how a sunken bomb ship has simply become part of the furniture. It was called Barbed Wire Island during WWI, because of how fortified it was with trenches, barbed wire and gun emplacements, preparing for a German invasion that never came. Five miles out at sea is a sight like something from War of the Worlds: seven abandoned red towers in a watery blue expanse, like tin boxes on legs, with walkways running between them: WWII sea forts where soldiers would live at sea for six weeks at a time, firing at incoming German aircraft.

A few miles from Sheerness, at Warden Point, a WWI sound mirror – huge concave concrete monoliths that were used to detect the engine noise of aircraft, before the time of radar – has fallen down the cliffs and lies cracked on the beach, a victim of erosion. The same rapid erosion that has been luring houses and caravans on Sheppey into the sea for decades, turning cliff-side communities into beaches. The same beaches that fossil collectors travel to from far and wide, for they are teeming with prehistoric snakes, crabs and shark’s teeth. Ghosts upon ghosts upon ghosts.


“What can I say about the ship?” said Laurie, 51, an artist who has lived on Sheppey since the age of four, and attended one of the talks organised by Ken a few years ago. “It just is. It's just there. We all presume it must be safe because it’s been left. Surely they wouldn’t let us carry on living here and building houses if it wasn’t safe? Right?”

sheerness beach cycle

A teenager cycling along Sheerness beach. Photo: Richard Splash / Alamy Stock Photo

Professor David Alexander is a master of disaster. For 30 years he has conducted risk and disaster research, and published books such as Natural Disasters (1993), Confronting Catastrophe (2000) and How to Write an Emergency Plan (2016). He has spent his life wondering ‘What if?’, before helping institutions prepare for every scenario that follows. He is currently involved in inquiries into both the Grenfell Tower Fire and COVID-19.

His article on the Sheerness shipwreck – titled, “The Strange Case of the Richard Montgomery: On the Evolution of Intractable Risk” – was published in the peer-reviewed science journal, Safety Science. It is a meticulous review of almost every major piece of research on the shipwreck, an analysis of its credibility, and then an academic investigation into the possible scenarios that could lie ahead. “It seems a tacit assumption by decision makers is that, left alone, the wreck would slowly become harmless,” he wrote. “There is no evidence to support this idea.”

“I’ve never been to Sheerness,” he told me, when we spoke over Zoom. “I plan to never go. I don’t ever want to see the Montgomery in person, because it would seriously give me nightmares.”


He wasn’t convinced by the tsunami idea. In his opinion, tsunamis require a big vertical displacement of water, and the Montgomery sits in fairly shallow water. Of much greater concern to him is the blast affect.

“When you see bombs go off in Hollywood films, it's basically just a can of petrol going up,” he said. “With real bombs, the fire is irrelevant – it's the blast. It makes buildings disintegrate, compresses vehicles, lifts people off their feet. That's to say nothing to what it does medically: how a blast affects the interior of the body. So, yeah, blasts are a big deal.”

His article described the case as “a rare example of ungovernable risk for which there are no easy solutions”. But he feels he exaggerated. He meant there are no cheap solutions. “It would be very expensive. Standard procedure means you would evacuate the entire area likely to be affected by it, before you start,” he said. “That would require up to 40,000 people to be evacuated for around six months, plus or minus. You'd probably need a consortium of salvage companies and the best experts on bomb disposal, and it still wouldn't be safe. You’d need to build some sort of temporary blast wall around Sheerness. And divert the shipping, which might have serious implications for the ports nearby.”

While combing through the National Archives during his research, he discovered declassified government meetings about the shipwreck dating all the way back to the 1960s. “Every meeting consisted of a number of people with no expertise being told what it was all about,” he said. “Then everyone would agree unanimously to do nothing about it. That was it. Over and over again. Decade after decade. For goodness’ sake. Inertia has created this situation.”


Last summer, on the 3rd of July, Lord Harris raised the topic for a one-hour debate in the House of Lords. Professor Alexander briefed him extensively beforehand. The discussion was lively. “If anybody wanted to cause serious trouble, they could put a bomb on a drone and decide to bomb the SS Richard Montgomery,” exclaimed Lord Berkeley. “Keep calm and carry on monitoring,” said Lord Patten. But the government minister who drew the short straw to answer questions in the dispatch box knew very little about the topic, and there were few repercussions to the debate.

Afterwards, Lord Harris told me, “Various former transport ministers came to me and said they saw the debate and that it was one of those things they were briefed about when they came into office, one of those, 'Oh, and by the way, minister, nothing to worry about, but you ought to know there is this wreck in the Thames.' They said they asked what could be done about it, but were told it was very difficult.”

A vacuum of accountability has opened up around the shipwreck, in which nobody is willing or able to make the major decisions needed to address the situation. The main responsibility lies with the Maritime and Coastguard Agency and the Department for Transport. After combing through their most recent survey reports of the shipwreck (from 2016 and 2017), I contacted them to request an interview with Camilla Moore, the Receiver of Wreck, but I was told she was on leave and unavailable for an interview. They passed me on to the Department for Transport, who told me they “won’t be available to partake” in my story, and redirected me back to the survey reports of the shipwreck I had already read.

“If this shipwreck exploded,” I asked Professor Alexander, “and anything close to the worst case scenarios occurred, would this be seen as a tragic and fatal failure of government?”

“In real moral terms, the answer is an emphatic yes,” he answered. “In terms of the reality of what might happen, we have to look and see what happens with COVID-19. We knew that was coming too. But when it came, the plans had been forgotten, shelved, ignored, and emergency planners had been sidelined and underfunded. I’ve been quite involved in the inquiry into Grenfell Tower, too. Some good work has been done. But the government has 32 QCs defending it, at an enormous and staggering cost to the taxpayer.

“So what is going to be the outcome of that? And what can we expect from a COVID-19 inquiry? And what would we expect from an SS Richard Montgomery inquiry? Some of the truth would come out, but would that actually mean justice? Would real culpability be established? This, I honestly wouldn't like to bet on. In a way, there ought to be an inquiry about the shipwreck right now. You have a situation of risk – some would say extreme risk. Can we honestly say the government has managed this in the best possible way?”

At the end of my day in Sheerness, I walked back along the beach for one last look at the SS Richard Montgomery. The sea was perfectly still, green water slopping on the shingle, shells of all shapes and colours, barely a wave. A thick haze sat on its surface and a mirage on the horizon made passing ships seem like eye floaters. The shingle banks stretched far out beneath the shallows, meaning a child could stand nearly 30 metres out and barely have water around their knees.

Families were sunbathing and swimming, dogs were being walked, and people queued at a beach bar advertising “thick shakes, candy floss and slush puppies”. And down on the stone beach steps, I found a poem written in large letters in thick white paint:

The masts of a liberty ship
Like little crosses
Mark the water not far out to sea
Fourteen hundred tonnes of high explosives
Buried in the belly of its liberty
Snapped in half on the sands of beyond.
All help
The truth of it - this wartime souvenir
Is common knowledge
But whisper to yourself
That you can see the end of the world from here.