The site is formed by the River Vattenån in the east and most of its upstream tributaries in the west, and includes more than 20 freshwater lakes, small mires, streams and some wet forests. River Vattenån supports one of the largest European populations of freshwater pearl mussel Margaritifera margaritifera outside the Russian Federation. The lakes and streams are important spawning grounds for brown trout Salmo trutta, on which the freshwater pearl mussel depend (the larvae grow on the trout’s gills). Nationally threatened species such as otter Lutra lutra and wolf Canis lupus are also present. The pearl mussels and other freshwater invertebrates are being monitored, as former forestry activities, pearl fishing, Rotenone insecticide use and the introduction of pike and char in some of the lakes have reduced the populations of trout and mussels. The Site is remote, but quite popular as a recreational area for fishing and hiking. There are cottages for public use as well as marked trails and information boards. Land use is mainly dedicated to nature conservation.