Water is important for the flora and fauna, local climate, soil and humidity in the national park.
Streaming, undisturbed watercourses are particularly valuable. The watercourses in the national park have a rich wildlife and plant life. Many different species of fish and benthic fauna live here. Several of them are sensitive to pollution and acidification which confirms the value of protecting the area. The White-throated Dipper and the Grey Wagtail are characteristic birds in the area.
Several small streams flow along the ravines. Ponds, wetlands and swamp forests provide valuable variation in the area and contribute to the significant biodiversity. Odensjön is the national park’s only natural lake, the ponds Härsnäsdammarna and the pond Skärdammen are landscaped.
Skärdammen was built in 1929 mainly to enhance the views from the tourist hotel situated where the current visitor centre is. Today the pond is very popular among visitors and birds alike with whooper swans nesting in the pond. Unfortunately the pond is a migratory obstacle. The new built bypass, built to imitate a natural stream, should enable migration from the coast and up the streams of the national park. The bypass will also be used for education.
The bypass is about 200 m long and varies in depth. All rocks were excavated during the buildning process while gravel were purchased in the region. The height difference is about 2 m and the fall is about 1%.
You are welcome to wade and play in the stream - everybody is welcome!
But please leave the rocks and stones where they are. The bypass is supposed to have different structures and water speed as different species have different demands on their environment.