Koryaksky reserve is distinguished by a rich hydrological network. It especially concerns the “Parapolsky Dale” area. Rivers and streams are numerous and full-flowing for most of the year, they are mainly snow-fed. The density of the river network in Parapolsky Dale is 1km/km², practically all big water-bodies are connected with each other.
In the basin of the Kuyul River there are about 10 000 lakes, the biggest of which is Talovskoye Lake with the water surface total area of 43.8 km². Lakes are numerous both in river valleys and in intermountain troughs. The largest among them are Potatgykhtyn Lake (the “Cape Govena” area) and Talovskoye Lake (the “Parapolsky Dale” area). The stream valleys of the “Cape Govena” and “Lavrova Bay” areas are gorge-like, often with canyons and waterfalls. The majority of streams are of mountain character.