The 44 hectare large Valdaora reservoir, dams the Rienza river which traverses the Val Pusteria.
In 1958, an artificial lake came into operation in the Val Pusteria, the 44 hectares large Lake Valdaora in the municipalities of Valdaora and Monguelfo. It is located next to the state road into the Upper Pusteria valley and dams the water of the Rienza river and its tributaries (Rio Anterselva, Rio Brunstbach, Rio Furkelbach and Rio Vila) for the Brunico-Valdaora Hydro. It can hold 4,800,000 cubic metres of water.
Lake Valdaora is a popular excursion destination. Nice hiking paths proceed around the lake, moreover the Pusterbike Cycle Route goes past it. Lake Valdaora is also well-known among fishermen, in summer fishing is allowed with a licence and in winter, the Valdaora Fishermen Association organises ice hole fishing.