Watchdog blames poor maintenance for repeated pipe bursts at Coulport depot

Radioactive water from the Coulport armaments depot, the UK’s secure storage site for nuclear warheads, leaked into Loch Long near Glasgow after repeated pipe bursts caused by poor maintenance, according to official files cited by The Guardian.

The Scottish Environment Protection Agency (Sepa) found that the Royal Navy failed to properly maintain a network of 1,500 water pipes at the base, leading to low-level tritium contamination in the loch. Tritium is a radioactive isotope used in nuclear warheads.

The documents, released after a six-year freedom of information battle by investigative site the Ferret and shared with the Guardian, reveal that up to half the base’s components were beyond their design life at the time of the leaks. The UK government had sought to keep the files secret, citing national security, but Scottish Information Commissioner David Hamilton ruled that disclosure risked “reputations” rather than security.

Sepa linked incidents in 2010, 2019 and 2021 to “shortfalls in maintenance” and “slow” progress on promised remedial action. In August 2019, a major burst flooded a nuclear weapons processing area, with contaminated water draining directly into Loch Long. While Sepa concluded the radioactivity levels posed no health risk, it criticised the Ministry of Defence (MoD) for “unnecessary radioactive waste” production and poor asset management.

An MoD spokesperson, as per The Gaurdian, said it placed “the utmost importance” on handling radioactive substances safely and that “there have been no unsafe releases” into the environment. Sepa has since reported “substantial improvements” at Coulport and Faslane, with no repeat of such incidents.