This was in the transfer document when control was passed to CRT from BW:
7.1
The British Waterways Board (‘British Waterways’) is a public corporation with a
statutory responsibility for operating and maintaining those waterways, docks and
harbours in Great Britain that were transferred to
it in 1963 as one of the successors to the
British Transport Commission under the Transport Act 1962 together with waterways and docks acquired or restored since then. British Waterways is required by statute to
maintain the majority of the waterways in a suitable condition for the craft which use
them. British Waterways’ 2,200-mile network of historic canals, rivers and docks is
visited by 13 million people a year and delivers an annual £500m in benefits to the
nation, from amenity, flood relief and employment to green infrastructure, neighbourhood renewal and wildlife corridors.
There is also a post on this forum discussing licensing of a boat (see section below in blue) http://www.canalworld.net/forums/index.php?showtopic=78861&page=64 Where CRT state:
"The Claimant believes that unless it is granted an Injunction against the Defendant, . . . . . . . . . . the Defendant will simply move or tow the Boat to another mooring on the Canal or another canal or inland waterway controlled by the Claimant such that these proceedings will not have achieved their objective and will not enable CRT to comply with it's statutory duty to ensure that the inland waterways controlled by CRT are safe, well-managed and properly conserved."
This to me is an admission that they have a legal duty to do maintain the waterways. Otherwise they can't use it as an argument against anyone else.