Eichener See

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

Eichener See

The Eichener See is a seasonal karst lake in the Southern Black Forest, Baden-Württemberg, Germany. It only fills with water when the groundwater level is high. There is no surface inflow; water leaves mainly through underground channels or by evaporation. The lake sits in a doline inside a muschelkalk-karst area, near the village of Eichen (part of Schopfheim), Hasel, and Wehr, about 2.5 km west of Erdmanns Cave and just south of the B 518.

Water levels vary greatly. In wet periods the lake can be up to about 3 meters deep above ground and about 250 by 135 meters in size (roughly 2.5 hectares). In dry times the water table can be as deep as 40 meters, with the deepest point around 48 meters below the surface. The surrounding caverns fill with water quickly but drain slowly.

The lake bed is planted with a rich meadow flora, which should not be grazed or fertilised during dry periods. The lake is home to the tiny fairy shrimp Tanymastix lacunae, one of the few places in Germany (and Europe) where this species lives. The drying and refilling cycle is essential for its life.

History and protection: Eichener See was first noted in 1771 after a capsized boat caused five drownings. A scientific description likely appeared in 1782 by Heinrich Sander. It has been protected since 1939 and, since 1983, designated a natural monument covering 3.75 hectares. It is also a European Special Area of Conservation.

The lake can appear or disappear within days, depending on rainfall and groundwater levels.