Resolve Marine Group cuts masts from SS Richard Montgomery ahead of schedule

Resolve Marine Group has completed the removal of three rusting masts from the SS Richard Montgomery, a World War II shipwreck resting in the Thames Estuary. The U.S.-built vessel, which sank in 1944, still contains an estimated 1,500 tons of munitions. The engineering firm finished the project earlier than planned and under the budgeted cost.

The Montgomery grounded on a sandbar off Sheerness, approximately 40 miles from London, while transporting explosives for the Allied forces after the D-Day landings. The ship broke apart during salvage attempts and settled on the seabed with its cargo intact. For decades, the masts protruding from the water served as a local landmark, but recent surveys indicated the structure was deteriorating.

Nolan Conway, a naval architect at Resolve Marine Group, stated that the vessel had begun to lean. He explained that the primary concern was the masts collapsing onto the cargo, which could trigger a detonation. Conway noted that some of the munitions are believed to have pressure fuses, meaning an impact from the falling structures could set them off. The goal of the project was to reduce the stress on the hull before that risk became critical.

To execute the removal safely, the team built a custom lifting frame designed to raise each mast without swinging or swaying. They also utilized a remotely operated underwater diamond-wire saw. This device clamps around the mast with hydraulic arms and cuts through the metal, allowing the work to proceed without divers entering the water.

U.K. Maritime Minister Keir Mather confirmed in the House of Commons that the project was completed on budget. The total cost was just under $13 million. Mather described the masts as having placed a heavy load on the structure, and their removal reduces the risk to the wreck. He said the work supports the long-term safe management of the site.

The explosives themselves remain in place because extracting them carries considerable risks. Experts disagree on the scale of a potential explosion. Conway said estimates range from minor effects on the shoreline to a tidal wave traveling up the Thames. He added that the outcome could also be a relatively minor event that might only close a nearby shipping channel. Officials currently judge the overall chance of an explosion to be low.

The government maintains an exclusion zone around the wreck, which lies about 1.5 miles off the Sheerness coast. Mather stated that the site will continue to be subject to continuous monitoring and control through that zone. The removed masts have been moved to the Historic Dockyard Chatham museum, where they will be displayed to recognize the ship's role in supporting Allied forces during the war.