Rehabilitation of the Cleuson-Dixence Pressure Shaft

The huge outflow of water flooded the mountainside, turning into torrents of mud and rock. Although the power produced by the Grande Dixence hydroelectric complex supplied 17 Swiss Cantons, representing one fifth of the storable energy produced in Switzerland, the Bieudron plant had to be stopped and its 1200 MW capacity halted until the end of 2009.

With damage to a major engineering structure on a destabilised rock mass, the rehabilitation of the complex proved lengthy and sensitive both in technical and safety terms. More than 9 years after the accident, refilling of the Cleuson-Dixence scheme draws to a close. This will restore the total power output of the Grande Dixence complex to 2000 MW, as the same quantity of water will be turbinated two to three times faster.

N.B.: The Valais Canton has 56% of Switzerland’s glaciers and represents the largest hydraulic reserve in Europe