The Blackball Coal Company's mine near Blackball was on the opposite side of the Grey River to the Stillwater - Westport Line, and in the late 19th century an aerial cableway was used to transport coal from the mine across the river to a railway station in Ngahere.
During 1909, the Public Works Department began carrying coal along the Blackball Branch, and in September that year, the State Mines Department began operating the Roa Incline.