Grand’Maison Dam

Description

Built between 1978 and 1985 and commissioned in 1987, the Grand’Maison Dam is one of Europe’s major hydroelectric structures. Operated by EDF, this facility has an installed capacity of 1,800 MW, making it the most powerful hydroelectric power station in France.

It connects Lac de Grand’Maison, at an altitude of around 1,700 metres, with Lac du Verney, further down the valley. An underground tunnel runs through the Rissiou mountain range, carrying water to the power station. When electricity demand is high, the water is released through the turbines to generate electricity. Conversely, when demand is lower and electricity is available, water is pumped from the lower reservoir back up to the upper one. This system makes it possible to bring a substantial amount of electricity generation capacity online very quickly.

This major construction project left a lasting mark on the history of Vaujany. During the works, the village welcomed many workers involved in building the facility. The income generated by EDF’s operation of the dam provides revenue for the municipality, helping it develop its facilities and tourism offer. The construction also permanently changed the landscape, particularly at Le Collet, where spoil from the works was used to reshape the terrain. Today, this area is home to a popular summer sports and leisure centre.

The dam is not open to visitors, except during the European Heritage Days. A public viewing point offers a chance to admire the structure and the surrounding mountain scenery.