By reducing tolls, the Aire and Calder managed to increase traffic from 179,295 tons in 1855 to 291,313 tons in 1863, but traffic gradually reduced after that, as railway links to the coalfields were built. The canal structures were increasingly affected by subsidence from the mining, and an inspection of the aqueduct in 1866 revealed ""fissures in the rock and cracks in the arches"". In 1870, Barnsley Corporation ordered the canal company to stop extracting water from the River Dearne, as they needed the supply. Faced with a dilemma, the Barnsley and the Aire and Calder companies negotiated, and the result was the Barnsley Canal Transfer Act of 1871, which authorised the takeover of the canal by the Aire and Calder, the replacing of ten of the twelve Walton locks by an inclined plane, and protection of the water supply at Barugh.