30In 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 [1951 c. 64.] Rivers (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 II of that Act) ".