Eutrophication is caused by the surrounding farms and the water that flows from the fields into the river.
For five years, Hushållningssällskapet Halland, together with landowners, has laid out about 20 wetlands along the river with successful results.
- The wetland acts as a natural filter, so nutrients that flow out of the fields end up on the bottom and the water becomes cleaner, says John Strand project manager for LIFE Goodstream.
Cameras show clear results
With the help of game cameras, Hushållningsällssällskapet can now show the public the rich wildlife that exists in and around the small river.
- We have seen small whales, herons, otters and lots of animals that you almost never see with your own eyes, says Sofia Hedman, nature conservation biologist at Hushållningsällskapet.
But there are clouds of unrest, the poison PFAS has been found in the nearby Kistingebäcken which empties into the Trönningeån river.
Hear more about the project in Trönningån in the clip above.