Lac d'Émosson
The Lac d'Émosson (Lake Émosson) is a reservoir in the canton of Valais, Switzerland. It is located in the municipalities of Salvan and Finhaut. The closest small city in Switzerland is Martigny. The lake has a surface area of 3.27 km² and an elevation of 1,930 m. The maximum depth is 180 meters. The purpose of the Émosson Dam is hydroelectric power generation. Water from the reservoir first powers the 189 MW Vallorcine Power Station downstream and just over the border in Vallorcine, France. Water is then sent through a headrace tunnel to the 190 MW La Bâtiaz Power Station, 12 km (7 mi) to the east in Martigny, Switzerland. The drop between the dam and La Bâtiaz Power Station is 1,400 m (4,593 ft).[1]
| Lac d'Émosson | |
|---|---|
 | |
  Lac d'Émosson  Lac d'Émosson  Lac d'Émosson  Lac d'Émosson  Lac d'Émosson | |
 Map | |
| Location | Valais |
| Coordinates | 46°4′18″N 6°55′10″E |
| Type | reservoir |
| Primary outflows | Barberine |
| Catchment area | 34.91 km2 (13.48 sq mi) |
| Basin countries | Switzerland, France |
| Surface area | 3.27 km2 (1.26 sq mi) |
| Max. depth | 161 m (528 ft) |
| Water volume | 227 million cubic metres (184,000 acre⋅ft) |
| Surface elevation | 1,930 m (6,330 ft) |
The first dam of Émosson (also known as Barberine Dam) was built in 1925. The current dam with a height of 180 m was constructed between 1969 and August 1973 and floods the old dam. The reservoir was fully impounded on 10 September 1975, it increased the reservoir's volume from 40 million m³ to 227 million m³.[1] The old dam can still be seen when the water level in the Lac d'Émosson is very low.
The lake serves as the lower reservoir for the 900 MW Nant de Drance Hydropower Plant which began operations in 2022.[2]
In 1955, another dam was built 300m higher above the now existing lake. This lake is now known as the Lac du Vieux Émosson.
The dam can be reached by road or by a funicular-train-funicular trip. The Funiculaire du Châtelard is the first used from the valley bottom, it is the steepest 2-cabin funicular railway in the world with a gradient of 87 percent.[3][4] Mini-Funiculaire d'Emosson runs next to the dam with a maximum incline of 73% for a difference of elevation of 140 m.
Construction of the new Émosson dam, 1971
Detail of the arch dam
Lac d’Émosson, viewed from Col du Passet
Mini-Funiculaire d'Emosson (2004)
The old gravity dam is visible when the water level is low
See also
Notes
- "Électricité Émosson SA" (in French). Electricity of Émosson. Archived from the original on 2 June 2012. Retrieved 29 April 2013.
- "20GWh pumped hydro energy storage plant starting operations in Switzerland". Energy Storage News. 29 June 2022. Retrieved 2 July 2022.
- The Châtelard funicular Archived 10 August 2014 at the Wayback Machine
- Funimag: Funiculaire Minifunic
External links
- Cycling profile for climb to Émosson (in French)
- Cable car and attraction park
- www.emosson.ch Archived 8 August 2014 at the Wayback Machine
Media related to Lac d'Émosson at Wikimedia Commons