a reservoir formed by the dam of the Saratov Hydroelectric Power Plant on the Volga River, in Saratov, Kuibyshev, and Ul’ianovsk oblasts, RSFSR. The reservoir was filled in 1967 and 1968. It occupies an area of 1,831 sq km and has a volume of 12.9 cu km, a length of 357 km, a maximum width of 25 km, and an average depth of 7m. The reservoir regulates flow on a daily and weekly basis. The water level fluctuates in the range of 0.5–1 m. The reservoir was created in the interests of power engineering and inland water transport. It is used as an industrial and municipal water supply and for irrigation. There is also fishing (European bream, pike perch, pike, carp). The many populated areas situated on the reservoir include the cities of Kuibyshev, Chapaevsk, Syzran’, Khvalynsk, and Balakovo.