Where a navigable watercourse is to be diverted in pursuance of an order under section 108(1) above or of any order or scheme falling within section 108(4) or (5) above, any new length of watercourse provided in pursuance of the order or scheme shall be such as will or, but for any bridge or tunnel constructed over or under it in pursuance of any order or scheme falling within section 108(4), would be navigable in a reasonably convenient manner by vessels of a kind which immediately before the date of the coming into operation of the order or scheme were accustomed to use that part of the watercourse which is to be replaced by the new length.

Where works for the diversion of a watercourse are carried out by a highway authority in accordance with any such order or scheme and any person suffers damage in consequence thereof by the depreciation of any interest in any land to which he is entitled or by reason of the fact that his right of access to a watercourse is extinguished or interfered with then, unless the works are carried out on land, or in the exercise of rights, acquired compulsorily in the exercise of highway land acquisition powers, that person is entitled to recover from the highway authority compensation under this subsection in respect of that damage.