There's no way that license fees -- direct to CART and indirect via marina fee slicing and commercial licenses -- can pay 100% of the cost of running the canals, and neither should they given the other sources of CART income including property, water extractions and the DEFRA grant, and the use of the canals as a resource by non-boaters.
But it's clear that they are artificially low, and -- even after the recent changes, which will take 5 years to come into effect -- are not graduated enough, the differences between different types of boats and boaters are too small, and there is insufficient enforcement of the rules about moorings, especially overstaying CMers.
Just like the current tax system this has been to the detriment of less well-off boaters with smaller older cheaper boats and to the advantage of better-off boaters with bigger newer more expensive ones, and also has favoured those who bend (or break) the rules to their own advantage (cheap living) while effectively penalising those who follow the rules.
It's also clear that the reduction of the government grant in real terms in recent years and even more so in the future is going to have a severe impact, and doesn't even make sense given their stated view of the canals as a "national treasure" or part of the national infrastructure -- but it's just another example of Tory privatisation-by-stealth, anything to get stuff to disappear off the government books and make it Somebody Else's Problem -- in this case CART, who can do very little about it.
The result of all this has been an ever-increasing maintenance backlog combined with more and more money spent on emergency repairs, more stoppages making it difficult for boaters to actually use the canals for -- well, boating, and a system parts of which are increasingly clogged up with CMers to the point of being well-nigh inaccessible to boaters who actually boat.
The problem is that the two things which would fix these problems -- restoration of the central grant (in real terms) to at least what it was when CART was formed, and a significant and rapid increase in license fees with more graduation (bigger and faster than CART have proposed, with a bigger surcharge for wideboats and CCers to discourage CMers) -- are being blocked, the first by the government and the second by the boaters who would be worse off as a result, including the NBTA... 😞