The Liberal Democrats have called for a full public inquiry into potentially catastrophic flooding at the Atomic Weapons Establishment site at Burghfield, in Berkshire during the 2007 floods.
The revelation came to light at the weekend, that the floods had disabled radiation alarm systems designed to detect an impending nuclear accident.
A report by the campaign group Nuclear Information Service (NIS) said electricity to "virtually the whole of" the Atomic Weapons Establishment site at Burghfield was switched off when it was flooded during torrential rain on July 20 last year.
"This is just not good enough," said Liberal Democrat shadow defence secretary Nick Harvey. "Nuclear weapons sites should be capable of withstanding attacks by enemies and terrorists, but these seem to have been unable even to resist the rain.
"A full inquiry needs to be held to get to the bottom of what happened and to ensure that such near misses can never take place again."