The River Tyne (Tunnels) Order 2005

30.  The Port Authority shall not be liable, in the absence of negligence or breach of any duty hereunder or otherwise, for any damage or injury howsoever caused to the new tunnel or to any of the authorised works (whether temporary or permanent) resulting from the dredging operations of the Port Authority or the carrying out by them in the execution of their statutory powers and duties of any operations in the river or works for the improvement or maintenance thereof; and it shall be a defence to any proceedings for an offence under article 38 of this Order arising from the carrying out of such dredging or other operations or works by the Port Authority that the same were reasonably necessary and carried out without negligence.