Where, in resisting a claim under this Part of this Act, a responsible authority contend that no enactment relating to the works in question confers immunity from actions for nuisance in respect of the use to which the claim relates, then if—
(a)compensation is not paid on the claim ; and
(b)an action for nuisance in respect of the matters which were the subject of the claim is subsequently brought by the claimant against the authority,
no enactment relating to those works, being an enactment in force when the contention was made, shall afford a defence to that action in so far as it relates to those matters.