PRINCIPAL TRENDS AND PROSPECTS OF THE USE OF WATER RESOURCES IN THE USSR

The increasing demand on water in the Soviet Union and the problem of assuring water quality require the construction of long-term water-management balances by drainage basins. These balances, based on predicted demand and water availability, would suggest the need for water-management projects within basins and interbasin transfers. Water needs would be evaluated both in terms of water requirements by categories of users and in terms of water quality. The most crucial regional problems involve the increasing shortage of water in Central Asia (with the prospect of interbasin transfer from Siberia) and in southern regions of the European USSR (with the problem of diverting water southward from the northern runoff slope). The Caspian Sea is expected to require a supplementary inflow of 80 to 100 cubic kilometers a year by the end of the century if the decline of its waterlevel is to be arrested. But southward diversion of northern waters is not expected to add more than 50 to 70 km³ at best, with a possible saving of an additional 10 to 20 km³ through decline of evaporation from a reduced Caspian Sea surface. The preservation of conditions in the Sea of Azov, the Aral Sea and Lake Balkhash pose additional water problems. [The senior author died in October, 1974].