Target species of Sharesalmo project are migratory fish, so river fragmentation represents one of the main threats to their survival because dams and barriers stop them and make their moving difficult. Ticino defragmentation was solved under other conservation projects, but the fragmentation of the Sesia River is a problem yet. In Sesia the Adriatic grayling survives, but its population is in a precarious situation because the part of the river suitable for the species has barriers that avoid fish movements. Sharesalmo makes this part of the Sesia river viable to Adriatic grayling (and to other species). The river part object of defragmentation is in Varallo municipality (VC), where there are two artificial barriers built for hydroelectrical use, one in Baraggiolo and the other one in Baraggia. Near each barrier Sharesalmo builds an artificial fish passage, that allows fish to overcome the barrier gap (both in ascent and descent directions), like a stair. There are different types of artificial fish passages, the Sharesalmo ones are subsequent basins: the gap to overcome is divided in several little basins, with hydraulic and geometric properties allowing fish moving.

RESULTS

Blue infrastructure: in 2019/2020 inspections were made and interventions were planned. At the end of 2020, the first steps were made, and the project team prepared for the implementation phase. On spring 2021 the job was assigned, and the construction has started. In April 2022 works are almost complete.

Strategies/action plans