The UK now has twice as many submarines in storage as it does in service, and has not disposed of any of the boats decommissioned since 1980, the National Audit Office (NAO) said in a scathing assessment.
The oldest of the submarines, HMS Dreadnought, has been laid up afloat at Roysth Dockyard for almost 40 years - double the length of time it spent on active duty.
Douglas Chapman, the SNP MP whose constituency includes the former naval base, said it was unacceptable that “consecutive British governments have for years ignored this issue and instead burdened the communities of Rosyth and Devonport with these ageing subs on their doorsteps”.
The estimated cost of disposing of a submarine is £96 million, the NAO found, while the MoD has put its total future liability for maintaining and disposing of the 20 stored and 10 in-service nuclear-powered boats at £7.5 billion over the next 120 years.
No submarines have been defuelled since 2004, when regulators said facilities did not meet required standards, with the process not due to start again until 2023.
Seven of the decommissioned vessels are moored at Rosyth, with the remainder at Devonport on the English south coast.
The project has been delayed for 11 years with a £100 million cost increase to £275 million, a £12 million annual bill for maintaining and storing the nine fuelled submarines and pressure on dock space at Devonport.
The NAO said the MoD does not have a fully developed plan to dispose of the operational Vanguard and Astute submarines or its future Dreadnought-class boats, which have different types of nuclear reactor
Meg Hillier, chairwoman of the Commons Public Accounts Committee, said: “For more than 20 years the Ministry of Defence has been promising to dismantle its out-of-service nuclear submarines and told my committee last year that it would now address this dismal lack of progress.
“It has still not disposed of any of the 20 submarines decommissioned since 1980 and does not yet know fully how to do it.
“The disposal programmes have been beset by lengthy delays and spiralling costs, with taxpayers footing the bill.
“The ministry needs to get a grip urgently before we run out of space to store and maintain submarines and we damage our reputation as a responsible nuclear power.”
Mr Chapman, MP for Dunfermline and West Fife, said: “This NAO report shines a light on an issue that I have been lobbying the UK Government on for some time. Working on a cross-party basis along with the MP for Devonport, Luke Pollard, I have urged the Government to deliver a properly funded programme to recycle these submarines which, saves the taxpayer money and moves these old submarines out of Rosyth forever.
“Last year we wrote a joint letter to the Prime Minister asking her to expand the civil nuclear clean-up budget to cover submarines. Not only would this deal with a longstanding problem, it would have the added bonus of creating jobs in West Fife. Submarine recycling should be seen as a new economic opportunity to spread our expertise and intellectual property around the globe – we must grab it with both hands.
“However as this damning NAO report points out it is unacceptable that consecutive British governments have for years ignored this issue and instead burdened the communities of Rosyth and Devonport with these ageing subs on their doorsteps.”
A MOD spokeswoman said: “The disposal of nuclear submarines is a complex and challenging undertaking. We remain committed to the safe, secure and cost-effective defueling and dismantling of all decommissioned nuclear submarines as soon as practically possible.”