Fortum and Oulun Energia to conduct breeding area study of migratory fish in the River Oulujoki

The study will examine potential breeding areas for migratory fish in the River Oulujoki and the feasibility of the study areas will be determined. Additionally, the significance of the study areas in terms of strengthening the breeding opportunities and natural circulation of migratory fish will also be reviewed. The work will begin in spring, and the results are expected to be ready by the end of August 2021.

Included in the seven study areas located in conjunction with the power plants are the diversion channels of e.g. Fortum’s Montta, Pälli and Nuojua power plants, and the old channel of Oulun Energia’s Merikoski power plant located in the heart of the city of Oulu.

“Together with Oulun Energia we will determine which of the study areas would best promote the breeding of migratory fish and natural circulation in the river,” says Fortum’s Environmental Specialist Katri Hämäläinen.

“Collaborating with Fortum enables the review of the river area as a whole. The study will provide important information on which areas, from the sea to Oulujärvi lake, would be the best for breeding areas,” describes Oulu Energia’s Quality and Environmental Director Tarja Väyrynen.

The study will be conducted by Sweco Rakennetekniikka Oy and is the first step for the later planning and possible implementation of the selected breeding areas.

Breeding area study is part of broader migratory fish collaboration in the Oulujoki water system

The study will use maps and topographic surveys to examine what kinds of water flows are technically feasible to direct to different areas, and what kinds of breeding areas might be possible. Then the water flow volume needed to create a sufficient size breeding area will be determined as well as how much gravel and rocks, for example, would be required for the realisation of a fry and spawning area.

“A preliminary feasibility study of the areas with the most potential will be conducted to assess the technical and economic feasibility opportunities of the breeding areas, and the natural lifecycle prerequisites based on small fish and smolt production analyses and the Natural Resources Institute Finland’s models,” Hämäläinen says.

The study is linked to broader efforts aiming to strengthen the natural circulation of migratory fish populations and fish in the Oulujoki water system. Thus the work supports also the ongoing Oulujoki water system vision in which regional municipalities, authorities, Fortum, and Oulun Energia are together mapping ways to develop the river area while harmonising natural fish populations and hydropower production.

“We already collaborate with Fortum in stocking fish and improving the recreational use of the river area through the Oulujoki OUMO voluntary project. The breeding area study is a good extension of this collaborative effort,” says Väyrynen.