Ortho-Tokoy Reservoir (Kyrgyz: Орто-Токой суу сактагычы) – a reservoir in Kyrgyzstan.
Located on the Chu River, 2 km west of the village of Ortho-Tokoy, on the border of the Naryn and Issyk-Kul regions. The construction plan of the reservoir was approved by the decision of the Central Committee of the Communist Party of the Soviet Union and the Council of People’s Commissars of the USSR on March 19, 1940.
Construction began in 1941 and was completed in 1960.
The elevation above sea level is 1700 m.
The length is 18 km, the maximum width is 5 km, and the maximum depth is 47 m.
The height of the dam is 52 m, length – 365 m, width – 6 m.
The length of the spillway tunnel is 567 m, diameter – 4.5 m. The average water flow is 12.8 m³/s. It regulates the flow of the Chu River.
The total area of the reservoir is 22 km², of which 17 km² are in Kyrgyzstan and 5 km² in Kazakhstan. The water volume is 470 million m³.