The masts of the SS Richard Montgomery, a U.S. Liberty ship carrying 1,400 tonnes of unexploded munitions, were successfully removed from its wreck in the Thames Estuary by October 19, 2026. This operation mitigates a decades-long public safety concern surrounding the sunken vessel.

This work addresses the risk of the masts collapsing onto the ship's unexploded cargo, a scenario that experts have warned could lead to an explosion capable of devastating a Kent coastal town and generating a tidal wave affecting London. The removal marks a significant step in managing the danger posed by the wreck.

What the Records Show

The SS Richard Montgomery was a U.S. Liberty Ship, built in 1943 by the St. John's River Shipbuilding Company in Jacksonville, Florida. In August 1944, loaded with approximately 7,000 tons of munitions, the ship was bound for the UK and then Cherbourg. On August 20, 1944, it dragged its anchor in shallow water and grounded on a sandbank near the Isle of Grain, about 250 meters north of the Medway Approach Channel. Intensive salvage efforts managed to remove about half of the cargo by September 25, 1944. However, a crack appeared in the hull, and the forward end flooded, forcing the abandonment of the salvage operation. An estimated 1,400 tonnes of explosives remain in its forward holds. The wreck has been designated as dangerous under the Protection of Wrecks Act 1973.

Timeline of Events

August 1944: The SS Richard Montgomery, carrying munitions for Allied forces, grounded on a sandbank in the Thames Estuary.

July 14, 2026: The government confirmed that work to remove the masts would begin in early September.

September 2026: Resolve Marine Group began the mast removal operation, constructing an underwater platform for specialist maritime engineers.

September 30, 2026: The third and final mast was safely cut and removed from the wreck.

October 19, 2026: UK ministers announced the successful completion of the mast removal project. The removed masts were transferred to The Historic Dockyard Chatham for conservation.

What Changed and For Whom

The successful removal of all three masts has reduced a direct structural risk to the wreck. The Department for Transport and the United States Maritime Administration oversaw the operation, which was carried out by Resolve Marine Group. This action addresses concerns that the masts, visible above the water for decades, could collapse onto the unexploded cargo. The existing exclusion zone around the wreck will remain in place, and continuous monitoring will continue. For the local communities and maritime traffic in the Thames Estuary, the site has been made