In paragraph 17(2) of Schedule 7 to that Act (which relates to the confirmation of byelaws made by a water authority under section 5 of the Rivers (Prevention of Pollution) Act 1951) for the words “section 5 of the M1Rivers (Prevention of Pollution) Act 1951” there shall be substituted the words “section 31(6) or 33(1) of the Control of Pollution Act 1974” and after the words “a stream” there shall be inserted the words “or the controlled waters (within the meaning of Part 11 of that Act)”.