Several stakeholders are working together to ensure that the Stångån River, located south of Sundsvall in Sweden, will once again become a completely free-flowing watercourse without barriers. This summer, two dams are being removed through a project led by Sportfiskarna (Swedish Anglers Association) and supported by the Open Rivers Programme.
Stångån is a tributary of the Ljungan River that has been closed to fish migration for hundreds of years. It flows roughly 30 km from Lake Torringen to its confluence with the Ljungan. Just a year ago, there were eight dams in the watercourse. Four of these were removed in 2024 and, in 2025, two more dams are due to be removed as part of a project funded by the Open Rivers Programme, which also includes one of the barriers removed in 2024.
The first of these is the Torringen dam and hydro-lake, which were used to store water during the summer period for energy production in autumn and winter. This created high/low flows that are completely contrary to natural river conditions and have therefore had a major impact on aquatic life. Demolition work on this dam began in early July and the dam is now fully removed.
Torringen dam during removal works, Sweden – July 2025 © Torbjörn Bergkvist
The Torrsjö hydroelectric facility dams the Stångån River and channels the water into an underground headstock pipe. The original 390-metre-long riverbed is almost entirely drained of water. The dam has been a complete obstacle to fish migration, but its removal is already underway.
The dam at Torrsjö power plant seen from downstream, Sweden © Sportfiskarna
These two barrier removals form part of a holistic approach to the catchment area. The watercourse and all eight lakes in the main river have not currently achieved good ecological status, partly due to lack of connectivity but also because of the changed hydrological regime due to hydropower. The project therefore contributes to restoring good ecological status in the Stångån River catchment area, beyond the barrier removal. The biggest single ecological benefit is that a more natural flow regime will be recreated, benefitting the biological diversity in the whole 223 km² catchment area.
Migratory species such as sea trout, eel and river lamprey are among those that will benefit in the long term. Stångån is the only major tributary of the Ljungan where these species can migrate for reproduction. There are also other species associated with Stångån’s unique environments, such as white-throated dippers, otters, resident trout and freshwater pearl mussels.
When the dams are removed, the ambition is to continue restoring the ecological functions within the catchment. This includes restoration after timber floating as well as wetland restoration. An important factor in achieving the overall approach in Stångån has been close cooperation with the company Torrsjö Kraft, which owns several of the dams. Torrsjö Kraft has also been able to receive compensation for their decommissioning costs from The Hydroelectric Environmental Fund in Sweden.
The Open Rivers Programme considers Stångån a unique project that provides a strong example of a whole-catchment approach and will continue to serve as a model for future river restoration projects in the area. More about this project.
Torringen dam during removal works, Sweden – July 2025 © Torbjörn Bergkvist
