First trout have been transferred upstream over the Leppikoski hydropower plant in Finland – Leppikoski Fishheart inaugurated

01 October 2021, 10:00 EEST

Leppikoski Paltamo

The Fishheart fishway at the Leppikoski hydropower plant in Paltamo was inaugurated on 1.10.2021. Since the start of its test use in August at Leppikoski, Fishheart has been used to successfully transfer many 60+ centimetre mature lake trout. All in all, the Fishheart fishway has transferred about 2,000 fish upstream from the Leppikoski power plant dam. In addition to trout, Fishheart has registered other fish species, including perch, lamprey, bream, vendace, whitefish, and pike perch.

Fortum’s goal is to strengthen the natural cycle of the threatened Oulujärvi lake trout in the vicinity of the Leppikoski hydropower plant in the Hyrynsalmi route. National Fish Way Strategy’s key sites in the Oulujoki river system for restoring fish migration are located in the Hyrynsalmi route which has breeding areas and habitats, a prerequisite for the natural life cycle of migrating fish.

“At Fortum, we want to find effective solutions that both support the strengthening of fish stocks and enable the production of renewable and climate-friendly hydropower. Each river and hydropower plant is unique, and thus solutions vary by river and hydropower plant. To enable fish migration, a variety of different tools and measures are needed. I am proud of the Finnish Fishheart fishway, which is a good alternative for hydropower plants such as Leppikoski with a tightly built environment. Fish passage is implemented quickly and, at the same time, we determine the potential for the natural life cycle of fish,” says Simon-Erik Ollus, Executive Vice President, Generation Division.

Dam by-pass solution is one prerequisite for the natural life cycle of fish

The inauguration of the Fishheart is part of a set of measures being implemented to strengthen the natural life cycle of lake trout. The tributaries upstream from the Leppikoski power plant provide potential habitats and breeding grounds essential for the life cycle of the trout population; this year there have been habitat restorations at Torvenkoski and Tolosenjoki. Moreover, we are annually stocking lake trout fry on the Hyrynsalmi route in an effort to strengthen the fish population that imprints to the river.

“The Oulujärvi lake trout can now migrate to spawning areas upstream from the Leppikoski dam. This autumn will be the first season that we’ll test the Leppikoski Fishheart system’s optimal functioning and see the numbers and species of fish migrating upstream. Based on the initial experiences and results, we’ll develop the operation and research with Kalasydän Oy, the Paltamo Fishing right owners’ association, and the Fisheries Authority,” says Fortum’s Environmental Manager Susanna Hyrkäs.

The hydraulic Fishheart fishway is a Finnish innovation enabling fish to migrate past obstacles. Fishheart is a floating, mobile system installed in the power plant’s tailrace channel; the system has an attraction flow that guides fish into the opening. Fishheart uses artificial intelligence to detect fish that swim into the tube and then moves them over the dam.

Fishheart has been used previously in a power plant environment at the Taivalkoski hydropower plant on the River Kemijoki and in Sweden. At Leppikoski, the Fishheart system will be tested until mid-October, and its use will continue next summer.

Leppikoski’s Fishheart is one of Fortum’s voluntary measures advancing biodiversity with the aim to improve habitats and strengthen populations.


Further information:
Susanna Hyrkäs, Environmental Manager, Fortum, susanna [dot] hyrkas [at] fortum [dot] com, tel. +358 40 158 1825

Pikku Juttu


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