I think there are two distinct problems with the only common ground, being actually water.
Firstly CART do not already have enough income to offset the degradation of the network, caused by natural ageing, wear and tear, and an increasingly stormy weather. Regardless of how efficient, or not, they are. This is going to become even more pronounced as the Government further reduces it's funding.
Secondly, the growth of the number of boats on the network, moving and parked up, just like cars on our roads, is causing environmental degradation, and a decline service delivery. Providing more roads, and even more carparking, is easy compared to enlarging the waterways and waterways facilities, to cope. And for how many more?
The debate, now for the waterways, exactly parallels that for the roading network. Ever enlarging the facilities is just kicking the can down the road.
So how is future supply going to be rationed? before roading and waterways systems become constipated and service levels decline to near useless?
Pricing is the obvious tool, but the consequence would be that the UK's CART waterways would become far far less egalitarian, and therefore loose a lot of their diversity, colour if you like, and for me, a huge amount of their charm.
They would become much more like the masses of salt water marinas, in temperate, and tropical climates, inhabited very largely by a monoculture of smug well healed, and very largely boring. More like the Thames if you like.