The Commissioners could build any or all of the five reservoirs. As well as having powers to borrow money to fund construction, they could collect rates from individual mills, which were based on the number of feet of fall in level at that mill. Any corn mill with less than 6 pairs of stones did not have to pay rates, while the Barley Bridge corn mill at Staveley was exempt. The Act also stated that the Commissioners were the only ones authorised to build reservoirs in the named valleys. This fact was overlooked by Manchester Corporation in 1962 when they considered building a reservoir for drinking water supply in Bannisdale.