The Evançon
From the Monte Rosa glaciers to Verrès Castle
The Evançon has shaped the Ayas valley. It rises at more than 3,000 metres, beneath the glaciers of Monte Rosa. It then runs down the whole valley, past Champoluc and Brusson, and joins the Dora Baltea at Verrès, at the foot of the castle that overlooks the mouth of the valley. Along the way it has carved deep gorges, formed waterfalls and traced meanders across the flatter stretches.
Trout, minnows and high-altitude flowers
The water of the Evançon is cold, clear and well oxygenated. Brown trout live in it, along with less conspicuous fish such as the minnow. There are also plenty of aquatic insects and a few amphibians.
On the banks, larch forests alternate with alpine meadows and scree. Each of these habitats has its own plants. Some are rare and protected, such as the edelweiss, which is adapted to the cold, the wind and the poor soils of the high mountains.
Water in great demand
The valley depends on its torrent. Its water irrigates the meadows, supplies the municipalities with drinking water and drives hydroelectric power stations. Such intensive use has consequences. Discharges from upstream, roads and dams that cut through natural habitats, and climate change, which is shrinking the glaciers and altering rainfall, all weaken the torrent.
What is being done to protect it
- Protected areas: some sections are subject to strict rules to preserve species and their habitats.
- Restored banks: works strengthen them and limit erosion. Local species are planted there, which hold the soil together and link natural habitats to one another.
- Visits and educational programmes: these explain to residents and visitors why the torrent needs protecting.
Hiking, cycling and fly fishing
The Ayas valley lends itself to many outdoor activities:
- hiking: many waymarked paths lead from the larch forests to the summer pastures, and up to the edges of the glaciers. One path follows the Evançon for part of its course;
- mountain biking: routes for all levels criss-cross the mountains of the valley;
- fly fishing: anglers come here in search of brown trout;
- white-water sports: canyoning descents are offered in the gorges of the Evançon.
