In the district of Erding, east of Munich, the Isen River is considered a rare gem among flowing waterways that still retains its natural meandering, deadwood areas, and gravel banks. However, the river has been obstructed by weirs and barriers, which severely hinder the historical spawning migrations of endangered fish species such as the nase, barb, and brown trout. To counter this decline, the Munich Water Management Office (WWA) is partnering with local hydropower operators to restore a continuous flow of the river over a stretch of 30 kilometers from the municipality of Isen to the Mühldorf district border. This initiative is also supported by the World Wildlife Fund (WWF), highlighting its significance for conservation efforts in Bavaria.