Water source: altitude 1,850m, upstream from Siviez

32km long! This is indeed the longest Bisse of the Valais region. Its course begins passing through the alpine regions of Tortin and Siviez and then cuts through a spruce tree forest up to the level of Haute-Nendaz. Its route continues towards the alpine region of Pra da Dzeu and rejoins the hundreds of larch trees of the mayens of Dzora. Traversing the Forêt Verte (Green Forest) it threads through to Tzoumaz. After jumping over the dévaloirs? hanging over Ecône, it finishes its course in a vertical direction to Saxon.



The inhabitants of this village in the plane of the Rhône must have been in dire need for water for their crops in order to undertake such an ambitious project in the 1860’s. In 1865, work begins under the supervision of a Belgian named Mr Laga. Unfortunately, for technical reasons, the development was interrupted and followed by legal proceedings that lasted around ten years or so. Finally, the work was taken up again in 1875 under different management.



Numerous different structures were built along the way; dry rock walls, tunnels for passages through rocks, and the passage of water through chenaux...some of which are still visible today.



In 1876, water was introduced for the first time into the canal and the Bisse began its working life up to 1964. In order to survey the function of the canal, three wardens were installed along its path. These men lived in well-equipped barns along the Bisse. In 1999, an association called “Garde du Bisse” (Guarding the Bisse) was created with the intention of reviving this canal that holds an important place in the history of the region of the Valais.