Roselend Dam

The Roselend Dam is an arch-buttress dam located 5 km east of Beaufort in the Savoie department of the Rhône-Alpes region in south-eastern France. It is located just west and below the Cormet de Roselend mountain pass. The dam was designed by Coyne et Bellier and construction began in 1955. The reservoir began to fill in 1960, the power station was operational in 1961 and the dam complete in 1962. It was constructed for the primary purpose of hydroelectric power generation and supports the 546 MW La Bâthie Power Station.

Design and operation
The dam has a maximum height of 150 m and a length of 804 m. It is 3 m wide at its crest and 22 m wide at its base. The dam has a structural volume of 945000 m3. Its reservoir, Lac de Roselend, can store 187000000 m3 of water and has a surface area of 3.2 km2. Directly over the river bed is the dam's concrete arch with a 215 m radius. Flanking it on either side are concrete buttresses supporting the dam wall. Water from the dam is transferred west via a 13 km long penstock to the underground power station in La Bâthie. At the power station, the water feeds six 91 MW Pelton turbine-generators. The difference in elevation between the power station and reservoir affords a hydraulic head (drop) of 1250 m. Water from the St. Guerin Dam, 5 km to the southwest at 45.65°N, 6.57944°W and Gittaz Dam, 4.5 km to the northeast at 45.71111°N, 6.64611°W, provide additional water to Lac de Roselend as well.