Koçköprü Dam and HEPP
The Koçköprü Dam is located on the Zilan creek in Van province, eastern Türkiye. It forms a reservoir of some 85 million m3 capacity. The primary purpose of the dam is irrigation and hydroelectric power generation. The project included the construction of a 4,350,000 m3 water impermeable clay-core rock fill dam with a structural height of 97 meters, and a length of 700 meters at its crest. A total of 3 million m3 of soil were excavated for the spillway, the powerhouse, and the foundation of the dam, while 120,000 m3 of river dredging were carried out for the tailrace.
Construction of the river diversion required two tunnels to a length of 635 meters and 685 meters respectively. Each tunnel was excavated through the left abutment to a diameter of 6.5 meters and lined with reinforced concrete to an eventual diameter of 5.5 meters. A 2,200-meter long water transportation tunnel was excavated to 4 meters, and lined with reinforced concrete to an internal diameter of 3 meters, delivering abundantly water for the irrigation of 15,000 hectares of land. The power plant comprises two 9 MW Francis turbines paired with their vertical axis synchronous generators.
Construction of the dam and HEPP commenced in 1987, and full site commissioning was achieved in 1992. The Koçköprü Dam and HEPP is owned and operated by the state company General Directorate of State Hydraulic Works (DSİ).