Revitalisation of the Inn

Like many other bodies of water in Switzerland, the natural development of the Inn at Celerina has been restricted over the last century by bank reinforcement. Following extensive revitalisation projects in Samedan and Bever, Celerina also followed suit. The project involved measures designed to restore parts of the Inn’s natural freedom of movement. In the process, various constraints – such as the expansion of the settlement, the needs of agriculture and tourism, and groundwater and flood protection – had to be reconciled with the planned environmental improvements. This led to the separation of protective and utilisation zones. The revitalisation work was completed in 2025.
 

The Inn in the Upper Engadine is home to Switzerland’s highest-altitude native grayling population. The fact that the population is able to sustain itself through natural reproduction at this altitude is remarkable and gives it national importance. A key objective of the project was therefore to enhance the natural grayling habitats in the Inn. In addition, target species from other animal groups as well as rare plants also benefit from the revitalisation.
 

1. Prior to canalisation, Lej da Spuondas was a meander of the River Inn. The creation of a central dam separated the river, resulting in the present-day body of still water, which serves as a local recreational area for Celerina. In addition to trout, grayling and minnow, mallards and
tufted ducks live and breed here. The area also provides a habitat for the target species, the white-throated dipper, while deadwood structures serve as protective shelters for fish. The tributary to Lej da Spuondas, with its structured watercourse and gravelly bed substrate, offers an ideal spawning site and juvenile habitat for grayling and brown trout.

2. Instream measures (irregular arrangement of boulders) were implemented to improve the environmental quality of the canalised Inn riverbed. This enabled the aquatic habitat to be diversified and ecologically enhanced in favour of trout and grayling, which are native fish species.

3. To ensure upstream connection with the River Inn, fish accessibility at Lej da Spuondas was optimised by refurbishing the fish ladder.