Regulation 4 Fish passes
(1)
The operator of every dam shall ensure that it is provided with a fish pass which facilitates the free passage of salmon at all times except during any period when, for natural reasons, the flow of the river at the point where the dam is located is so low that salmon would not reasonably be expected to seek passage.
(2)
In this regulation “natural reasons” means any reason which is not related to—
(a)
the operation of the dam, or
(b)
the abstraction of water from the river by the operator of the dam or for a purpose for which the dam was constructed or is being used.