Biggesee

The Biggesee or Bigge Reservoir (Biggetalsperre) is a reservoir in Germany. It lies in the southern part of the Sauerland between Olpe and Attendorn. The lake serves to regulate the rivers Ruhr and Lenne as well as providing water for the Ruhrgebiet. It is fed from the Bigge, a tributary of the Lenne. The lake serves primarily to store water for the Ruhrgebiet so as to maintain the same level of water in the Ruhr. The lake can deliver, via the rivers Bigge and Lenne, up to 40% of all the water supplied by all the reservoirs in the river system of the Ruhr combined. A hydroelectric power station produces around 24 million kWh electricity annually. The power of the three large and one small Francis turbines amounts to 17.52 MW. The owner of the lake is the Ruhrverband. Along with the Listertalsperre, the Biggestausee forms a large reservoir system. The formerly self-standing Listertalsperre joins immediately on to the Biggesee. In middle of the Biggesee itself is the circa Gilberginsel which, together with the neighboring lakeshore area, forms a nature reserve. In 1956, the Landtag (parliament) of North Rhine-Westphalia passed a law for the financing of the Bigge Dam. On 1 August 1956, the Bigge Dam Law came into force. According to this, each municipality was obliged to extract 1.2 pfennigs from every consumer of water for every m2 of water they used – the so-called "Biggepfennig" – which went towards financing the construction of the Bigge Dam. The building of the dam began in 1956 and was finished in 1965, although the planning could be said to reach back as far as 1938. The Listertalsperre, dating from 1912, became an arm of the new reservoir. The complete system encompasses a volume of water of 172 million m3, of which the Biggesee has 150 million and the Listertalsperre 22 million. Therefore, the Biggesee system is the fifth largest reservoir in Germany in terms of capacity. The catchment area of both lakes comprises an area of . The lakes themselves have a surface area of with a length of ca. .