For 800 years, the barrier at St. Jyndevad Mill has restricted fish from accessing 100 kilometers of watercourses in the upper part of the Vidå river. Danish Municipality Aabenraa (Southern Denmark) is now starting work to create free passage at the site, reports Danish EAA member Danmarks Sportfiskerforbund.
Restoring free fish passage at St. Jyndevad Mill
In June 2022,
EAA Danish member Danmarks Sportfiskerforbund drafted a list of “worst barriers In Denmark”. Since the start of their work, the removal of the barrier at St. Jyndevad Mill has been selected as a major priority. This barrier – located at Sønderå in the Vidå river (Region: Jutland) – currently prevents migratory fish from reaching 100km of watercourses in the river’s upper part. Areas where most important spawning and nursery areas are located. The dam poses a barrier to the river's fauna, including the rare and critically endangered houting.
According to historic documentation, Sønderå has been dammed since the Middle Ages. Moreover, the Mill Pond, which was built in 1357, has made it difficult for the fish to pass. The dam has therefore been designated as an important focuspoint in the Danish State Water Basin Plan 2021-2027.
Now, however, Aabenraa Municipality is starting to create a fauna passage that includes an approximately 1.3-kilometre-long new stream, which will give fish such as houting, salmon, trout and lampreys free passage past both the approximately 2.5-metre-high dam and the Mill Pond, which for centuries has been a barrier for the fish on their way to spawning and nursery grounds.
Photo credits: Aabenraa Municipality 2025
Design of the project
Focus on both the watercourse and the surrounding nature
The new river’s course will be designed to meet the ecological requirements needs of migratory fish species. Specifically, four areas featuring shallow streams will be established to offer optimal spawning conditions for the fish.
Preparations have begun, with excavation expected to start in April 2025. The construction work is estimated to take around six months. Upon completion, the area will offer improved accessibility for visitors, including a new path along the stream and a bridge over the water.
The project has a budget of approximately DKK 21 million (2.815.638 EUR) and is financed with support from the European Maritime, Fisheries and Aquaculture Fund (EMFAF), the Danish State and the Municipality of Aabenraa.
"The project also has a strong focus on the nature around the watercourse. Sønder Ådalen is an internationally protected natural area, and we are working to ensure that both fish, insects, birds and bats have better habitats. Approximately 20 hectares of new nature will be established around the new river, while the Mill Lake will be preserved”, says biologist in Aabenraa Municipality, Torben Hansen.
Restoring river connectivity is key for improving the state of our freshwater ecosystems and dependent species
This local project is a great step forward for the connectivity of European rivers and the EU’s freshwater fish species population rates. Especially as freshwater migratory fish populations have declined by 93% in Europe within the last 50 years! Also, Europe’s rivers remain the most fragmented in the world, with a mean density of 0.74 barriers per kilometre.
The European Anglers Alliance have been very vocal on the issue of free-flowing rivers – such as under the
Living River Europe Coalition (LRE). Restoring free-flowing river supports the achievement of many pieces of existing EU legislation such as the Nature Restoration Regulation, the EU’s Water Framework Directive, and many others.
Kaare Manniche Ebert – representative of EAA member Danmarks Sportsfiskerforbund – adds, “river regulation has been a common practice in European rivers for decades and in this particular case centuries! Restoring river connectivity has many benefits for nature (nutrient balance, sediment transport, and ecological flows) and for society. This as free-flowing rivers allow EU citizens to access the river and enjoy outdoor activities as angling. We look forward seeing the completion of this project and hope that many freshwater species can reach – after so many centuries – their natural spawning grounds.”
More information
You can read more about the project on the municipality's
website
EAA member Danmarks Sportsfiskerforbund
website
Belletti, B., Garcia de Leaniz, C. Jones, More than one million barriers fragment Europe's rivers, Nature, 588(7838), 436-441. (
Link)
EAA position on the nature restoration law and free-flowing rivers:
Link