A ‘Doomsday wreck’ packed with enough explosives to unleash a tidal wave in the Thames is deteriorating faster than feared and part of it must be removed urgently.

The SS Richard Montgomery sank in the Thames Estuary in August 1944, coming to rest at a depth of 49ft with 1,400 tons of explosives still in her hold.

Her three masts still loom above the surface and plans have been made to remove them over fears that they could collapse on to the deck and trigger a blast.

But now action must be brought forward after a new assessment discovered corrosion on the masts is worse than expected.

Southend Labour councillor Lydia Hyde, who’s familiar with the latest findings, said things have reached a point where it’s safer to act than to do nothing.

A Ministry of Defence report in 2021 said that an explosion could cause a 15ft-high tsunami and cause ‘mass damage and loss of life’. 

A ‘doomsday wreck’ packed with enough explosives to unleash a tidal wave in the Thames is deteriorating faster than feared and part of it must be urgently removed. The SS Richard Montgomery sank in the Thames Estuary in August 1944, coming to rest at a depth of 49ft with 1,400 tons of explosives still in her hold

The SS Richard Montgomery was an American vessel carrying munitions for the allies in the Second World War

She said: ‘There was an assessment in the summer, and then there was a more detailed one in November to basically go and look at the condition of the masts.

‘The concern is that corrosion means they catastrophically fail, their structural integrity goes, the mast falls down and then lands on the wreck, and then that could set off an explosion.

‘Following the dive, they’ve assessed it and they’ve gone “Actually, no, we need to bring this forward because the corrosion was more than expected”.

‘So they’ve got to be taken down.’

The SS Richard Montgomery was an American vessel carrying munitions for the allies in the Second World War.

The SS Richard Montgomery sank off Medway in Kent and has lain on the seabed for nearly 80 years

A Ministry of Defence report in 2021 said that an explosion could cause a 15ft-high tsunami and cause ‘mass damage and loss of life’. Above: A 3D image of the vessel on the seabed

The ship is holding 1,400 tons of explosives that could go off at any time

It’s feared she still holds enough explosive power to unleash a tidal wave in the Thames, earning her the nickname the ‘Doomsday wreck’.

Estimates vary as to the potential height of such a wave – some say 16ft, some just 3ft while others believe there would be no wave at all.

But Ms Hyde believes the impact would be real enough in Southend, more than five miles away.

She said: ‘If that blast was to go off then we’re talking about the windows blowing out on the seafront.

‘I don’t know what the risk to life is at that distance – it might be quite small directly from it.

‘But if it’s enough to blast out your windows, knock people over, and knock people into things, then things could fall on them, so it could be quite dangerous for pedestrians.’

She estimated it would be ‘more severe’ on the Isle of Sheppey – the wreck is less than two miles from Sheerness, the island’s second-largest town.

Plans to remove the masts were first made in 2020.

At the time, the responsible ministry – the Department for Transport – said the masts could be ‘placing undue strain on the rest of the vessel’.

Plans to remove the masts were first made in 2020. At the time, the responsible ministry – the Department for Transport – said the masts could be ‘placing undue strain on the rest of the vessel’

A Department for Transport spokesman said: ‘Our priority will always be to ensure the safety of the public and reduce any risk posed by the SS Richard Montgomery

A sign warns seafarers not to approach the wreck, which is in poor condition

The Ministry of Defence also warned that an explosion could cause damage to nearby oil and gas facilities in Sheerness

But the work has been delayed for years and the masts still stand.

Hyde said they were now slated for removal in March.

She said: ‘It’s obviously been there for a number of decades now, but over time the metal is going to rust.

‘Even though it’s been fine up until now, over time it is degrading and it’s just tipped through that threshold now where the safe thing to do is remove the masts.

‘There’s significant planning and expertise that’s going into this so we don’t expect there to be a catastrophic incident.’

A Department for Transport spokesman said: ‘Our priority will always be to ensure the safety of the public and reduce any risk posed by the SS Richard Montgomery.

‘We commissioned experts to carry out vital surveying work to the wreckage.

‘Based on their findings, we are now reviewing and updating our plans to remove the ship’s masts as soon as safely as possible.’

What is the SS Montgomery and why is it dangerous?

The SS Richard Montgomery was a US Liberty Ship built in 1943 to transport cargo across the Atlantic 

The 7,200-tonne vessel safely crossed the Atlantic on convoy HX-301 without incident and was ordered to anchor off Sheerness. 

The vessel was carrying some 7,000 tonnes of munitions and it was due to carry on to Cherbourg to unload its cargo. 

However, on August 20, 1944, the Montgomery dragged her anchor and ran aground on a sandbank around 250 yards from the Medway Approach Channel. 

The SS Richard Montgomery, pictured, sank in 1944 off the coast of Kent carrying 7,000 tonnes of munitions that were due to be shipped to Cherbourg for invasion of Europe

The SS Richard Montgomery dragged its anchor on August 20, 1944 and ran aground on a sandbank before her hull cracked and started flooding 

A major salvage operation was launched to unload the vessel’s deadly cargo although, within 24 hours cracks began appearing across the hull and the forward areas began flooding. 

By September 25, the salvage operation had to be abandoned after the entire vessel flooded.  

The Richard Montgomery was one of 2,700 Liberty ships built during the war.