several reservoirs in the area including Norman Hill, Piethorne, Kitcliffe, Ogden, Rooden and Hanging Lees. The importance of the brook to the locality was recognized by the Oldham historian Edwin Butterworth, circa 1837, when he marked the brook as the River Haugh in one of his early maps of the Oldham district. Name One explanation of the brook's name is that "pie" is short for magpie, and "thorne" for hawthorn, both bird and bush re common in the area. The lowest mill on the brook was called Salt Pye Cotton Mill in the 19th Century. The name "salt pye" is connected to the old packhorse routes and signifies a building, on or near a packhorse route, used for the distribution of salt from Cheshire. Mills Butterworth, writing in 1828, described the area above Newhey, where Piethorne Brook enters the River Beal; he wrote that "there are many woollen mills, supplied with numerous streams of water". The earliest woollen mills were established at farmhouses; Kitcliffe Farm had a fulling mill, powered by a wooden waterwheel, and some of the mill structure can still be seen. In the 19th century, larger mills were built below the brook's confluence with Wickenhall Brook, to use the waters for processing rather than power. The mills were Ogden Mill (bleaching and finishing), Wood Mill (fellmongering), Haugh Mill (woollen), Haugh Mill (cotton), and Salt Pye Mill (cotton waste spinning). Each mill, apart from Haugh Mill, had a reservoir or millpond fed by the brook; Ogden Mill had a reservoir and millpond. Another mill, Lower Two Bridges Mill, took water from the River Beal and also from the brook via the discharge from the Salt Pye Mill reservoir. The latter mill subsequently changed its name to Two Bridges Mill and, after 1919, to Coral Mill. Reservoirs Oldham Corporation began work on Piethorne Reservoir, to be fed by the brook and Cold Greave Brook, in 1858, and it was completed and filled ten years later. It was found that the brooks carried moorland silt into the reservoir and Hanging Lees Reservoir was built as a (silt) settling reservoir, and Norman Hill Reservoir as a higher reservoir. A stone-step cascade, or man-made waterfall, was built for the brook to pass from Norman Hill into Piethorne Reservoir. Diverting the brooks' waters resulted in a significant reduction of flow into the lower brook. In consequence, and as a result of the Gas