This summer, Finland’s first downstream migration route with catching equipment for migratory salmon has been introduced at Haapakoski rapids on the Iijoki river. The downstream migration route was implemented as part of the extensive Iijoki river migratory fish project 2020–2022. The route was introduced to the media and public at the opening ceremony held on 22 August 2022.
“Excellent cooperation leads to innovative solutions. The downstream migration route at Haapakoski rapids is a unique solution both nationally and internationally. Its implementation has required significant investments in research and development, as well as an open-minded approach to deployment,” stressed Antti Kurvinen, Minister of Agriculture and Forestry, in his speech at the ceremony.
“By working together with various parties, we have taken a solid step forward in the downward migration of migratory fish at Haapakoski rapids. Going forward, we will test the downward migration solution and develop it further based on the results we get. Research, interactive cooperation and progressing in phases are the key to gaining tangible results to benefit migratory fish in the future too,” says Jani Pulli, managing director of PVO-Vesivoima Oy.
The downstream route for migratory salmon fry, or smolt, at Haapakoski rapids consists of the downstream migration route and a guiding fence. The first part of the downstream migration route has accelerated flow. The purpose is that smolt come to the route entry along the guiding fence, notice the flow and swim to the route attracted by it. Then, the fish are directed either to the catching equipment or along the tube to the power plant’s lower channel to continue their migration. The first smolt entered the route already in the summer of 2022.
“This summer we tried underwater photography along the first section of the route. The conditions for taking pictures are challenging, but it looks as though it could give us important information in coming years about the behaviour of the fish at the route’s entrance and the number of the fish,” explains Mirko Laakkonen, the project manager in charge of the Iijoki river migratory fish project 2020–2022 in the Council of Oulu Region.
The downstream migratory route is in use each year from mid-May to the end of July. The migration of the smolt is estimated to peak at Iijoki river in early June, when the water temperature is about 10 to 12 degrees Celsius. During the first years, the aim is to direct the smolt to the catching equipment and transfer them with a fish truck downstream of the lowest power plant, Raasakka. If the downstream migration equipment turns out to be functional and efficient enough, similar structures will be built on other dams in the Iijoki river. The aim is to enable the fish to migrate from upstream to the sea.
The actual costs of the downstream migration route were approximately EUR 1.8 million. The route will be further developed in the ‘Lohi Iijokeen’ project that starts this autumn. The project also focuses on monitoring fish through extensive research.
Some of the actions taken by the Iijoki river migratory fish project 2020–2022 include the construction of the downstream migration route in Haapakoski and planting of fry, as well as the transfer and monitoring of salmonids. The project is implemented by PVO-Vesivoima Oy, the Lapland Centre for Economic Development, Transport and the Environment, the Ministry of Agriculture and Forestry of Finland, the municipalities of Ii, Oulu, Pudasjärvi, Taivalkoski and Kuusamo, the Council of Oulu Region, Iijoen Vesistön Kalastusalue (the Iijoki Waters Fishing Region), Metsähallitus, the Centre for Economic Development, Transport and the Environment for North Ostrobothnia and the Natural Resources Institute Finland. The project coordinator is the Council of Oulu Region. The total project budget is some EUR 2.2 million.
The project is funded by the migratory fish programme NOUSU by the Ministry of Agriculture and Forestry of Finland. The project improves the living conditions of migratory fish and aims to restore the natural breeding of migratory fish populations in Finnish rivers.
Additional reads: Suomen ensimmäinen alasvaellusväylä vie Haapakoskella lohenpoikaset uudella tavalla voimalaitoksen ohi – Maa- ja metsätalousministeriö (Finland’s first downstream migratory route at the Haapakoski rapids transfers salmon fry in a new way past the power plant – Ministry of Agriculture and Forestry of Finland) (in Finnish: mmm.fi)
Read more about the Iijoki river migratory fish cooperation project 2020–2022 (link: Iijoen vaelluskalahanke 2020-2022 – Pohjoisen puolesta avoimessa yhteistyössä (Iijoki river migratory fish project 2020–2022 – Open cooperation for the North) (in Finnish: pohjois-pohjanmaa.fi)
Mirko Laakkonen, project manager, Iijoki river migratory fish project 2020–2022, Council of Oulu Region, tel. +358 40 685 4036, mirko.laakkonen(at)pohjois-pohjanmaa.fi
Jani Pulli, managing director, PVO-Vesivoima Oy, tel. +358 50 386 2680, jani.pulli(at)pvo.fi