Klingnauer reservoir is an artificially dammed lake in the Swiss canton of Aargau. He is in the water castle of Switzerland, on the lower course of the river Aare between Klingnau and Koblenz, shortly before its confluence with the Rhine. The reservoir was created in the construction of a power plant in the 1930s, is now a nature reserve and an important habitat for endangered bird species. It is about three kilometers long and at its widest point 500 meters wide.
The population of the lower Aare valley had been damaged in past centuries, over and over again by floods. Shortly before the end of the 19th century, a flood protection embankment was built on both sides of the river, which reached almost to Koblenz from Böttstein up. During the construction of the dam, a large watercourse was cut off on the west bank; by a Altwasserlauf was ( very calm waters, which is only fed by seepage water).
In 1900 the construction of the hydroelectric power plant Beznau took place south of the lake today. The Altwasserlauf was filled with the excavated material of the headrace partially. On the surface thus created spruce were planted. About half of the Altwasserlaufs (area about 23 hectares ) remained as riparian forest and is now a nature reserve.
During the First World War another power station would be built north of Klingnau. It was built in an access bridge. But then feared the investors, the current not being able to sell and let fall the project. The semi- finished bridge remained a ruin left. This so-called half-bridge was demolished in the fall of 2005 for security reasons.
From 1931 to 1935, a second power plant at Klingnau was then still built, but about two miles to the north ( and about a kilometer before the Aaremündung ). The Aare river was dammed and greatly reduced the flow rate. It was formed by a flood embankments limited lake. Within a few years, the new lake has developed into a wintering ground of northern migratory species or breeding ground and habitat for native birds. Also, the beaver has become home again in recent years.
Klingnauer reservoir is today a Wetlands of national importance, which will be expanded in the coming years.