Tainionvirta River restoration set to boost endangered fish populations in Central Finland

The Tainionvirta River, flowing into Lake Päijänne, is set to become more accessible for endangered fish species, which will enhance their chances of reproduction. Restoration work has begun, including the removal of the Virtaankoski dam and the construction of a natural river rapids, facilitating the spawning of trout in the area. Additionally, plans are in place for a fish passage at the Maatiaiskoski dam, enabling fish to migrate upstream to Joutsaan, covering several kilometers.

The removal of migration barriers is expected to significantly impact the overall salmonid populations in the Päijänne area. The restoration of the Virtaankoski began in November after years of anticipation. The outdated hydropower dam will be replaced with a natural setting, as it currently yields very few trout fry.

With the dam gone, a hectare of spawning area will emerge, and fish will gain access to nearby lakes and side streams suitable for breeding. The owner of the hydropower station plans to apply for a permit to build the fish passage, as it is currently the only barrier for fish migrating from the Nuoramoisjärvi upstream.

Despite challenges related to long-standing permits and regulations, the restoration project is on track, with completion anticipated by February 2025. It is hoped that trout will start breeding as soon as next autumn. Overall, the transformation could yield over seven hectares of spawning grounds if the entire Tainionvirta opens for fish, substantially benefiting the local ecosystem. Each improvement will contribute to an increased habitat for migratory fish in Central Finland, addressing the limited spawning streams that currently feed into Päijänne.