A nuclear water leak was shocking news in the UK. There was a leak of radioactive water into the sea from the base that holds the UK’s nuclear bombs. It happened after old pipes repeatedly burst, and official files have revealed the incident. A regulator found that the Royal Navy failed to properly maintain a network of 1,500 water pipes on the base.
More shockingly, the reviews filed repeated leaks into the sea. The reports show a pipe burst at Coulport in 2010 and a further two in 2019. There were two further pipe bursts in 2021. The Scottish Environment Protection Agency (Sepa) revealed the information for the leaks.
Nuclear Water Leak: Failure of the Royal Navy
There was a leak of Radioactive water into the sea from the base that holds the UK’s nuclear bombs. It happened after old pipes repeatedly burst, and official files have revealed the incident. There was a leak of radioactive material into Loch Long, a sea loch near Glasgow in western Scotland. A regulator found that the Royal Navy failed to properly maintain a network of 1,500 water pipes on the base.
In fact, the armaments depot at Coulport on Loch Long is one of the most secure and secretive military sites in the UK. It holds the Royal Navy’s supply of nuclear warheads for its fleet of four Trident submarines, which are based nearby. Therefore, nuclear water leaks should not be expected here.
Radioactive Waste with Tritium
The Scottish Environment Protection Agency (Sepa), a government pollution watchdog, compiled files reporting nuclear water leak . They suggest that up to half the components at the base were beyond their design life when the leaks occurred.
Sepa said shortfalls in maintenance were the leading cause of the flooding at Coulport. The flooding resulted in the release of unnecessary radioactive waste in the form of low levels of tritium. Tritium is one of the materials in nuclear warheads.
Secret Files Released: Reputations Threatened
In a report of the agency in 2022, the agency blamed the leaks on the navy’s repeated failure to maintain the equipment. They must keep the equipment in the area devoted to storing the warheads. The report also said plans to replace 1,500 old pipes at risk of bursting were sub-optimal. A cache of confidential inspection reports and emails revealed the leaks. The emails were given to the investigative website the Ferret and shared with the Guardian. However, Sepa and the Ministry of Defense fought to keep the facts secret.
David Hamilton, the Scottish information commissioner, ordered the release of the information about the leaks. He polices Scotland’s freedom of information laws. The revelation happened after a six-year-long battle by reporters for access to the files. The UK government insisted the files had to be secret for national security reasons. However, Hamilton ruled that most had to be released. He said their disclosure threatened “reputations,” not national security. The MoD asked for more time to review them, citing “additional national security considerations”. However, the information was published.
Nuclear Water Leak: History of Pipe Bursts
Nuclear warheads are fitted onto the UK’s supply of Trident missiles at Coulport. The agents load missiles onto Vanguard class submarines before they head to sea for secret patrols as part of the UK’s nuclear deterrent. The UK’s nuclear weapons fleet has been at Faslane on a neighboring loch called Gare Loch since the early 1960s. Tritium is regularly replenished in the warheads to maintain the performance of the weapons. The Sepa files show there was a pipe burst at Coulport in 2010 and a further two in 2019. One leak in August 2019 released “significant amounts of water” that flooded a nuclear weapons processing area. As a result, it became contaminated with low levels of tritium and passed through an open drain that fed into Loch Long.
Sepa said radioactivity levels in that incident were very low and did not endanger human health. In particular, it found there were “shortfalls in maintenance and asset management leading to nuclear water leak. Therefore, it led to the failure of coupling, which indirectly led to the production of unnecessary radioactive waste.
More Bursts and Floods After 2019
After an internal investigation and a Sepa inspection, the MoD promised 23 actions to prevent more bursts and floods in March 2020. Its lack of preparedness had led to confusion, a breakdown in access control, and inadequate communication of the hazards. However, there were two further pipe bursts in 2021. It includes one in another area that also held radioactive substances, prompting another inspection by Sepa in 2022.
Sepa said the progress on completing the 23 remedial actions had been slow and delayed in many cases. However, the events have highlighted shortcomings in asset management across the naval base. David Cullen is a nuclear weapons expert with the defense think tank Basic in London. He said the repeated pollution incidents were shocking and the attempts to keep them secret were outrageous. He said the MoD is almost 10 years into a nearly £2bn infrastructure program at Faslane and Coulport. Yet, they didn’t have a proper asset management system as recently as 2022. This negligent approach is far too common in the nuclear weapons program and is a direct consequence of a lack of oversight.
Campaigners’ Objection: Ministry of Defense Refuses to Explain
In fact, one expert describes the revelations as “shocking” and condemns attempts to keep problems secret. Campaigners said that poor maintenance at a nuclear weapons base was deeply concerning. The Ferret reported in May 2025 that there had been 12 nuclear incidents that could have leaked radioactivity at Faslane since 2023. The Ministry of Defense said the incidents had actual or high potential for radioactive release to the environment. Meanwhile, it refused to give any details of what happened.
A navy review in 2020 assessed vulnerabilities, defects, and corrosion in several systems at Coulport. It found that about 50 per cent of the components reviewed were beyond design life. Sepa said nobody expects a mature management system to make such a huge mistake making nuclear water leak.
