Otmuchów Lake is a dam reservoir and retention reservoir built in the years 1928 to 1933, known by the former name Staubecken Ottmachau and situated on the river Nysa Kłodzka, just to the North of the town Otmuchów. At the maximum level of damming at 18.6 metres the reservoir has an area of 20,6 km² and the capacity 130,45 hm³.The reservoir closes its drainage basin of the river Nysa Kłodzka at an area of 2352 km². The capacity was newly estimated in 2001 at 130,45 mln m³, after the river sedimentation in the reservoir had reached 215 metres.
The ceremonial opening of the reservoir with the name Ottmachauer See and commissioning of the hydroelectric power plant occurred on the 17 June 1933. The four turbine hydroelectric power plant, located at the outflow, has two Kaplan turbines with the power of 4.8 MW and supplies energy to the power grid of the country. The flow is at a rate of 2 × 21.5 m³/s at 16 m level difference.
Address 48-385, Poland
Coordinates 50°27'50.45" N 17°7'8.315" E