Undens FVO

Lake Unden in Tiveden is classified as national interest. It is a rift valley lake, about 40% of the total inflow is groundwater that comes through the bottom of the lake. Unden is one of our country's leading large char lakes, both the lake's topography and its ecosystem are suitable for char. Unden has clear cold water, the average depth of the lake is 34 m and the greatest depth is stated to be 108 m.

Unden's area is 9540 ha and the lake has 13 streams as tributaries. Draining takes place through three power plants located in Edsån, which connects Unden with lake Viken. The average water flow in Edsån is 3.5 m3 per second. Göta Kanalbolag AB, which has the original water rights, supplies Göta Kanal with the required water level for navigation.

In the lake there are char, trout, whitefish (3 varieties), pike, perch, lake, Norway pout, roach/leg, roach, roach, and yaw. The biggest fish caught in Unden are; char 10.5 kg, trout 14.4 kg, whitefish 3.2 kg, perch 2.8 kg and pike 17.0 kg.
The trout spawn in running water in the larger streams. The newly hatched trout live one to two years in the hatching stream, and then go out into the lake and eat themselves big. After a few years, a number of these go back to the birth stream for new spawning.

The tributary streams and Edsån which connects Unden with Viken does not belong to the fisheries management area.