A watchdog has disclosed that a base allowed irradiated water to discharge into a Scottish loch on multiple occasions due to inadequate maintenance.
Files released by the investigative journalism platform The Ferret, originating from the Scottish Environment Protection Agency (SEPA), indicate that radioactive water from the UK’s Coulport weapons depot escaped into Loch Long in western Scotland multiple times following bursts in aged pipes.
This Royal Naval Armaments Depot houses nuclear warheads for the British Royal Navy’s Trident-class submarines. SEPA stated that approximately half of the depot’s 1,500 water pipes had exceeded their designed operational lifespan at the time of these leaks. The agency attributed the flooding, which released trace amounts of tritium—a radioactive substance found in warheads—into the loch, to “shortfalls in maintenance.” Loch Long is a popular spot for swimmers, divers, kayakers, and fishers. While small quantities of tritium are typically benign, extended or significant exposure can heighten cancer risks.
These documents indicate that pipes ruptured in 2010 and twice again in 2019. In August 2019, an area dedicated to warhead processing was inundated, leading to contaminated water discharging via an open drain into the loch. SEPA affirmed that the tritium levels were minimal and presented no risk to public health.
The UK Ministry of Defense committed in 2020 to implement measures aimed at averting further ruptures. However, SEPA subsequently observed sluggish progress on these initiatives, noting that asset management issues remained. Two additional pipe ruptures occurred in 2021, one of which was in another location containing radioactive substances, prompting a further SEPA inspection in 2022.
These documents were made public following a six-year legal battle pursuant to Scottish freedom of information legislation, as reported by the newspaper. In June, Scottish Information Commissioner David Hamilton determined that the majority of documents should be disclosed, dismissing the military’s assertions that national security required confidentiality. He stated the primary risk was to “reputations,” not safety. Although SEPA confirmed that radioactivity levels in these occurrences were very low and posed no threat to human health, the agency identified “shortfalls in maintenance and asset management that resulted in the failure of the coupling, thereby indirectly contributing to the generation of unnecessary radioactive waste.”
In May, The Ferret detailed 12 nuclear incidents at the Faslane Royal Navy submarine base since 2023 that potentially released radioactive substances.