freshwater body in eastern Kazakhstan, in a hollow between the Altai and Tarbagatay mountains at an elevation of 1,266 feet (386 m). Formed by the Irtysh (Ertis) River, which enters the lake in the east, it was originally 60 miles (100 km) long, 20 miles (32 km) wide, and 26 feet (8 m) deep, with a surface area of about 718 square miles (about 1,860 square km). Its level has been raised 20 feet (6 m) since it became part of the Bukhtarma Reservoir downstream, which is 375 miles (603 km) long and has a total area of 2,125 square miles (5,500 square km). Fishing—sturgeon, sterlet, carp, and others—is important, and there are shipping services.