By 1898, reservoirs at Swinburn and Colt Crag had been completed, and a new reservoir at Catcleugh was in progress. The water was conveyed to Hallington by pipelines and aqueducts, and when flows from there to Whittle Dean exceeded per day, the aqueducts overflowed with a corresponding loss of water. The company looked at building a new pipeline with a capacity of per day, but when they presented a bill to Parliament they had decided on a new tunnel, running parallel to the existing tunnel near Ryal, into which water would be fed by a pipeline from the Hallington reservoir. The Act also allowed them to build a narrow gauge railway from Matfen, at the eastern end of the tunnel, to Wylam, on the River Tyne, via Whittle Dene. An extension from there, across the river to connect to the North Eastern Railway was also authorised, and the bill passed through Parliament unopposed, becoming an Act of Parliament in August 1898.