Grand Bisse de St-Jean
After restoration works lasting two years, water can now once again flow down the length of the Grand Bisse de St-Jean. An easy walk between Grimentz and Mayoux follows the route of these irrigation channels typical of Valais.
The Grand Bisse starts from the Torrent des Marais (Grimentz), crosses St-Jean d’en Haut and finishes at Mayoux. All along its course it collects water from a number of small mountain streams. The upper part of the bisse runs through concrete conduits, whose open sections allow the water to flow beneath the open skies. After St-Jean, the bisse falls by 40 m and runs into a stone bed.
Description
- Abandoned since the late 1950s, the Grand Bisse de St-Jean has recently been restored to allow water to flow once again. Two years of targeted work were needed to achieve this:
- The clearing of the bisse
- The dredging of the bed
- The construction of small sluices
- The installation of conduits for some sections
- The consolidation and repair of the banks in accordance with clearly-specified standards
- The Grand Bisse de St-Jean has a dual function:
- Tourism : the Grand Bisse provides a pleasant family walk, graded “easy”, with the various restoration works on the Bisse having opened up sights of additional interest along the way
- Agricultural : along a small section of its course, the bisse has had its original function restored, and some farmland across from Mayoux is again irrigated by its waters.
Practical information
- Grading :T1
- Length :3.9 km
- Access :From Grimentz (post office), follow the signposts to St-Jean and descend towards La Gougra
- Altitude of starting point :1430 m
- Altitude of finishing point :1260 m
