Geographical Reference: Toktogul Reservoir is formed by the dam of the Toktogul Hydroelectric Power Station on the Naryn River, located in the Osh region of the Kyrgyz SSR. Its filling began in 1974. Area: 284 km²; volume: 19.5 km³, length: 65 km, maximum width: 12 km, average depth: 69 m, maximum depth: 180 m; the water level fluctuates within 63 m. Elevation above sea level is 880 m.
Climatic Conditions: The climate at Toktogul Reservoir is hot and moderate. Air temperature in summer reaches 35-38 degrees during the day and 22-25 at night. Wind conditions are moderate. Winters are snowy and not very cold. Water temperature in summer reaches 25-27 degrees. The thermocline occurs after 35-42 meters. The lake does not freeze over.
Diving at Toktogul Reservoir is quite interesting. Overall, the shores of the lake consist of clayey rocks. However, closer to the Toktogul Hydroelectric Power Station, the lake narrows and forms a rocky canyon that is 14-16 km long and 300-600 m wide. This is where all the diving takes place. The canyon can only be accessed by water. Steep cliffs and scree exclude any possibility of reaching it by land. The depth of the canyon varies from 120 to 180 m. The height of the surrounding cliffs reaches 400 m. Visibility in the canyon reaches 15-18 m, but drops sharply after depths of 18-22 m to about 4-6 m. The water in Toktogul is warm in summer, reaching 25-27 degrees. The thermocline occurs after 40 m. Schools of fish are often encountered. The lake is home to carp, crucian carp, silver carp, marinka, white amur, and trout. Large specimens of silver carp and white amur, reaching 10-12 kg, are often found. During our last trip, we discovered small jellyfish (10-12 cm in diameter). The lake also has a large population of shrimp. Underwater, the canyon is rich with vertical and negative walls, rocky peaks, and small grottoes. Occasionally, submerged trees and bushes can be found.
