Until 1960 the Aral Sea was considered the 4th largest lake in the world by surface area. The Aral Sea has two main inflows - the Amudarya and Syrdarya rivers with about 30 tributaries. From early 1960s because of extensive water use - unreturned withdrawal of water for irrigation and consequent drying up of many tributaries before reaching the main rivers - the water level in the Aral Sea began falling very rapidly. In 1965 the Aral Sea received about 56 cubic km of fresh water yearly, but this number fell to zero by the early 1980s.
By 1990 the level of the Aral Sea water fell by more than 17 m, the volume of water decreased by 75%, the salinity of seawater increased up to 30 g/l, and the surface area of the sea reduced from 66,400 sq. km to 31,500 sq. km.
The ecological situation in Aral Sea zone has became very dramatic. It has led to the changing of climate in the region, irrigated soils becoming deserts, deterioration of underground and surface water quality, reducing of available water for domestic and agricultural needs, loss of Aral Sea fishing and transportation importance, numerous other problems and finally put the health of present and future generations under threat.
This situation not only does not promote further development of the economy of the region, but has also caused damage with irreparable negative consequences. The fact is that the basis of the regional economy is fishing and other associated businesses. Since Uzbekistan is most agricultural country its economy has serious complications. In order to prevent further deepening of this catastrophe and to improve the present situation in this area the Government of the Republic of Uzbekistan has developed a series of measures: in particular it developed efficient water use schemes, changing the cotton situation (that during the Soviet period was grown as monoculture) by planting less water-consuming varieties, reviewing using of fertilizers in agriculture etc. The Aral Sea drought became an international disaster. World Bank, UNESCO, BMBF and others attacked the problem to protect the Aral Sea.