If a 'doomsday wreck' carrying a s**t tonne of bombs actually explodes in London, an expert has revealed what a worst case scenario would look like.
The SS Richard Montgomery, an American liberty ship, has been stuck at the bottom of the River Thames Estuary near Sheerness, Kent, for over 80 years.
Destined for Cherbourg, France, it arrived at the Thames carrying around 6,000 to 7,000 tonnes of munitions on 20 August, 1944.
How did the 'doomsday wreck' sink to the bottom of the Thames?
Whilst the vessel was ordered to anchor off Sheerness at the Great Nore, a force eight gale caused the anchor to drag. The heavy ship drifted away while the middle of it was grounded on a sandbank as the tide receded.
When the tide fell, the ship broke in half and the bombs were never fully offloaded.
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It now lies in shallow waters, partially submerged, with its masts visible above the surface.
Why should we care? Well, the Montgomery is decaying at an alarming rate, and it may or may not explode at any moment.
Worst case scenario if 'doomsday wreck' explodes
David E. Alexander, Professor of Emergency Planning and Management at University College London, told LADbible that a worst case scenario was put together by the Royal Military College of Science way back in 1970.
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They warned that a five meter high tsunami was possible if everything on board exploded at once.
This 'amounts to 14,283 bombs of very different kinds, and 1434 tons of TNT', said Professor Alexander.
However, he notes that the 'one thing that makes this unlikely is that the bombs are of many different types, and it's hard to see how they would all explode at once'.
Where will the 'doomsday wreck' explode?
So, in a worst case scenario the risk expert says the blast could cause significant damage 5.1 kilometres away from the wreck.
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"Sheerness, which is 2.4 kilometers away," he explained. "You can walk along the front or the beach in Sheerness, and you can see the mast of the Montgomery, and it would include parts of the Medway estuary and the Isle of Grain, which is 5.1 kilometers from the wreck.
"Along the Isle of Grain, facing the wreck, there are 28 petroleum storage tanks and five natural gas holders, which are about the size and shape of the Royal Albert Hall.
"You also get ships passing very close to the Montgomery, within 200 meters of it, mainly container ships, a few cruise ships, but rarely, and natural gas. Liquefied natural gas ships, which are about five stories high, they usually contain three tanks full of liquefied natural gas.
"It’s remarkable that none of them have run into the Montgomery over the last 80 years, given how close they pass by."
Three ways the 'doomsday wreck' might explode
1) Collapse of the structure
Although this year's annual survey suggested that the ship is decaying faster than expected, Alexander says that it only applies to the outside of the ship. They don't know what's going on in the inside.
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"Well, you might get some form of triggering, some form of explosion through the collapse of the structure of the ship," he said.
"Bits of the deck are subsiding. Bits are falling off the edges, simply because mild steel in cold water is going to decay over time. Indeed, some of the Russian ships in the Baltic, the steel is like wet cardboard.
"Now, they were built to an even lower standard, so the ship itself is falling apart, and that might have some influence."
2) Navigational error
"The second possibility is either a navigational error or a malfunction of a passing ship that sends it to the Montgomery," the professor suggested.
3) Terror attack
He said that there was extra surveillance around the Montgomery when the 2012 Olympics was going on in London.
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Although a possibility, he doesn't see it happening.
"But I don't believe that continued afterwards. On the other hand, even though a novel was actually published about a terrorist attack on the Montgomery, in 80 years, nobody has done it," Alexander noted.
There is no guarantee that the 'doomsday wreck' will explode
The professor said we can't be certain that the wreck will explode and even if it did, a tsunami isn't likely.
"We had the case of an absolutely massive explosion of 50 tons of TNT at Silvertown on the River Thames in the direction of Gravesend in 1917... It broke some windows in central London, but that was all," he recalled.
"This is far enough away that it is pretty unlikely that much would happen if there were a tsunami.
"It could wash across the isle of grain and proceed up the Thames. On the other hand, to have a tsunami, you tend to need much deeper water than we've got here.
"So we might have a wave effect caused by blast, but I'm not convinced that it will produce a very large wave."
Proposals to remove the bombs from the ship with robots
The reason why the bombs haven't been removed is because it's simply too dangerous of an operation. Although the professor claims there is one company out there who could do it.
"We talked to SMIT Salvage, which is the world leader in marine salvage Dutch firm. They said they could do it," he insisted.
"They could make the Montgomery safe and salvage what's needed so it could be removed from the site. I will put my faith in it. I don't know what they were charged for it, but anyway, they haven't been asked to do it.
"It was suggested that if they did this, they would need to evacuate the Isle of Sheppey for up to a year."
He added: "I think they could build a temporary glass wall along the front at Sheerness, possibly the same along part of the Isle of Grain and do it.
"They will probably need robots. They would need a lot of care. It would be a very difficult and sensitive and delicate operation, but I think we have enough salvage expertise that it could be done."
The Department for Transport say the Montgomery's condition remains 'stable and experts are continuing to monitor the site'.
Anish Vij