SS Richard Montgomery is a wrecked American Liberty ship that was built during World War II. She was named after Richard Montgomery, an Irish officer who fought in the British Army during the French and Indian War and Pontiac's War and then in the Continental Army during the American Revolutionary War.

She was wrecked on the Nore sandbank in the Thames Estuary, near Sheerness, Kent, England, in August 1944, while carrying a cargo of munitions. About of explosives remain on board presenting a hazard whose likelihood of explosion is variously asserted to be low to moderate.

Construction

Richard Montgomery was laid down on 15 March 1943 under a Maritime Commission (MARCOM) contract, MC hull 1199, by the St. Johns River Shipbuilding Company, Jacksonville, Florida. She was sponsored by Mrs. Rockwell, the wife of the director of MARCOM, Production Division, and was launched on 15 June 1943. She was the seventh of the 82 Liberty ships built by the yard.

Service and sinking

She was allocated to Agwilines Inc. on 29 July 1943. In August 1944, on what turned out to be her final voyage, the ship left Hog Island, Philadelphia, where she had been loaded with 6,127 tons of munitions.

She travelled from the Delaware River to the Thames Estuary, then anchored while awaiting the formation of a convoy to travel to Cherbourg, France, which had come under Allied control on 27 July 1944, during the Battle of Normandy.

When Richard Montgomery arrived off Southend, she came under the authority of the Thames naval control at located at the end of Southend Pier. The harbourmaster, responsible for all shipping movements in the estuary, ordered the ship to a berth off the north edge of Sheerness middle sands, an area designated as the Great Nore Anchorage.

On 20 August 1944 she dragged anchor and ran aground on a sandbank around from the Medway Approach Channel, in a depth of of water. The general dry cargo Liberty ship had an average draft of , but Richard Montgomery was trimmed to a draft of . As the tide went down, the ship broke her back on sand banks near the Isle of Sheppey about from Sheerness and from Southend.

A Rochester-based stevedore company was given the job of removing the cargo, which began on 23 August 1944, using the ship's own cargo handling equipment. By the next day, the ship's hull had cracked open, causing several cargo holds at the bow end to flood. The salvage operation continued until 25 September, when the ship was finally abandoned before all the cargo had been recovered. Subsequently, the vessel broke into two separate parts, roughly amidships.

Status and risk

thumb|Map of the Thames Estuary indicating the wreck of Richard Montgomery, and locations of proposed airports: 1. Cliffe; 2. Grain (Thames Hub); 3. Foulness; 4. Off the Isle of Sheppey; 5. Shivering Sands ("Boris Island").

thumb|upright|Warning buoy marking the wreck of SS Richard Montgomery (masts visible to left)

According to a 2008 survey, the wreck is at a depth of , on average, and leaning to starboard. At all states of the tide, her three masts are visible above the water.

Due to the presence of the large quantity of unexploded ordnance, the ship is monitored by the Maritime and Coastguard Agency and is clearly marked on the relevant Admiralty charts. In 1973, she became the first wreck designated as dangerous under section 2 of the Protection of Wrecks Act 1973. There is an exclusion zone around her monitored visually and by radar. The exclusion zone around the wreck is defined by the following co-ordinates:

In the report of a survey conducted in 2000 by the Maritime and Coastguard Agency the wreck still held munitions estimated by DERA as containing approximately of explosives. This comprises the following items of ordnance:

  • 286 × high explosive "GP" bombs
  • 4,439 × bombs of various types
  • 1,925 × bombs
  • 521-580 fragmentation bombs and 2,297 cases of fragmentation bomb clusters
  • Various explosive booster charges, smoke bombs (including white phosphorus bombs) and pyrotechnic signals it was determined that if the wreck of Richard Montgomery exploded, it would throw a -wide column of water and debris nearly into the air and generate a wave high. Almost every window in Sheerness (population circa 20,000) would be broken and buildings would be damaged by the blast. News reports in May 2012, including one by BBC Kent, stated that the wave could be about high; though lower than previous estimates, this would be enough to cause flooding in some coastal settlements.

When the condition of the munitions was originally assessed there was concern that copper azide, an extremely sensitive explosive, would be produced through reaction between lead azide and copper from fuze components (lead azide would react with water vapour, rather than liquid water, to form hydrazoic acid, which could react with copper in the detonating cap to form copper azide).

Critics of government assurances that the likelihood of a major explosion is remote argue that one of the fuses of the 2,600 fused-fragmentation devices could become partially flooded and undergo the reaction producing copper azide. A knock, such as caused by the ship breaking up further, or a collision on the busy shipping lane, could cause the copper azide to explode and trigger an explosive chain reaction detonating the bulk of the munitions. The Maritime and Coastguard Agency (MCA) said in 1998, "as the fuses will probably all have been flooded for many years and the sensitive compounds referred to are all soluble in water this is no longer considered to be a significant hazard". The wreck site has been surveyed regularly since 1965 to determine the stability of the structure, with a diver survey being completed in 2003. The report states that "Whilst significant structural collapse does not appear to be imminent, surveys suggest that this prospect is getting closer."

The 2010 survey report, Mayor of London Boris Johnson said that engineers had found the wreck would not prevent construction of an airport, and the wreck area would have to be considered. A Department for Transport (DfT) spokesperson said however, that the ship remained stable and the likelihood of an explosion was remote; the matter of the ship was unrelated to the ongoing development of the aviation strategy. The Ministry of Defence warned that the collapse of a mast could detonate ordnance, and Royal Navy specialists would need to remove them safely. In December 2021 it was reported that a contractor supported by the Navy would remove the ship's masts, starting in June 2022. At the end of June 2022 it was reported that the work to remove the masts would be delayed another year. In June 2023, unidentified objects found on the seabed around the ship caused the original plan to remove the masts to be deemed as too dangerous, and the removal was, again, delayed. In December 2023, the MCA determined that the masts had degraded more than expected and scheduled their removal for March 2024. In April 2024 18 metallic objects were found around the wreck and work delayed again.

In May 2025, the Secretary of State for Transport restricted flying below within a radius of 1 nautical mile of the wreck.

In April 2026, a £9.5 million contract was signed for the removal of the masts amid concerns that the site was vulnerable to drone attack or underwater sabotage. This was soon followed by calls for the masts to be preserved and put on display in Sheppey and Southend upon removal.

In media

Saturday-Night Theatre first broadcast in 1979 on BBC Radio 4 the crime drama Blockbuster — scripted by Stephen Barlay, adapting his own novel of the same name — of a blackmail conspiracy to obtain a million pounds from the Bank of England under the threat to cause a detonation of the wreck of the SS Richard Montgomery and so destroy the East End of London. The drama starred Brian Cox, Malcolm Hayes, Haydn Jones, Peter Woodthorpe, and Frances Jeater.

The SS Richard Montgomery was the subject of a plot line in season three of the BBC one drama Waking the Dead from 2003, in the episode titled "Walking on Water".

In the 2018 Indian movie Vishwaroopam II, the SS Richard Montgomery is the target of an attempted terrorist attack using caesium weapons.

In the second season of the National Geographic documentary series Drain the Oceans, broadcast in 2019, the story of the SS Richard Montgomerys sinking and the status of the wreck was the third story of an episode.

In the second series of the Sky political thriller COBRA, broadcast in 2021, the SS Richard Montgomery, (unnamed in the series), explodes as a consequence of undersea earthquakes, with the consequences predicted in the 1970 BBC report: heavy flooding and property damage in Sheerness with great loss of life — including that of the local MP.

See also

  • — WWII shipwreck in the Irish Sea containing explosives.
  • List of accidents and incidents involving transport or storage of ammunition

Notes

References

Bibliography

  • Maritime and Coastguard Agency website page, including links to survey reports. Updated periodically with new publications.