In 1979, Lake Kemnade was completed as the last impounded lake along the course of the River Ruhr so far. The lake is located between the towns of Witten-Heven and Bochum-Stiepel, and was created by the Ruhrverband following a commission from the company Freizeitzentrum Kemnade GmbH (FZK). It is primarily used for various recreational activities. As a side effect, it contributes to water purification.
The weir has four openings equipped with hydraulic gates. A fish ladder and boat chute are situated right next to the weir. At times of maximum flood, the entire installation is submerged. A power plant is currently under construction.
The Ruhrverband is authorised to lower the water level of Lake Kemnade by 20 centimetres to balance off low water levels in the River Ruhr. In 1995, the Ruhrverband took over management of the Kemnade impounded lake. However, leisure activities continue to be managed by FZK.