The Cregg River once powered three watermills, of which the converted Cregg Mill is the remaining example. The three mills stood together around the Cregg Mill bridge. The bridge there consists of seventeen arches, but only one arch is currently used. The nineteenth century Ordnance Survey Ireland maps show that the river was much wider at that point. However, due to artificial changes to the water level of Lough Corrib and the canalisation of the river, the river is now much narrower.