|A gricultural activity is a sector consuming the main volume of water resources (for agricultural needs up to 90% of the consumed water is used).|
Since the 60s irrigated territories in the region have been increased 2 times - to 7.5-7.7 million hectares, the population of the region increased 7 times exceeding 50 million people. Due to this fact growth of water consumption led to stop flow of the two main river systems of the AmuDarya and SyrDarya into the Aral Sea. Water deficit in watering period became considerable even in Kyrgyzstan and Tajikistan, which have many water resources.
Poor use of modern agro-technology, unsatisfactory technical conditions of irrigation and water distribution systems, wear out of the equipment, lack of water saving technologies led to water quality deterioration, salinisation of irrigated territories, swift development of desertification.
|Years||Sources||Farming drinking||Agricultural water supply||Industrial technical||Fishery||Irrigation||Others||Total|
|from surface (transboundary)||0||20||0||100||7960||185||8265|
|from surface (local)||0||10||60||50||2040||100||2260|
|re use of CDW||0||0||0||0||100||300||400|
|from surface (transboundary)||0||0||0||0||350||0||350|
|from surface (local)||48||20||6||5||4120||0||4199|
|re use of CDW||0||0||0||0||84||0||84|
|from surface (transboundary)||0||102||150||30||9198||20||9500|
|from surface (local)||175||333||199||110||232||0||1049|
|re use of CDW||0||0||0||0||370||0||370|
|from surface (transboundary)||145||40||289||35||22274||0||22783|
|from surface (local)||0||0||0||0||0||0||0|
|re use of CDW||0||0||0||0||45||0||45|
|from surface (transboundary)||0||0||450||350||35040||0||36240|
|from surface (local)||0||0||0||530||7280||0||7810|
|re use of CDW||0||0||0||0||3800||0||3800|
|Total water intake in the region on the average is 137.46 km³|
A number of natural and human factors influence water quality. Among natural factors one can point out formation of suspended particles, especially in mountainous regions, after heavy rain or intensive melt of snow and ice, and water mineralisation depending on soil kind of river beds. To the human factors: discharge of pollutants in water reservoirs.
|The water use efficiency in the Aral Sea Basin is 62 percent. This figure includes the effect of re-use, which may have resulted in some "hidden double counting."|
|Balance item||Average||Up||Middle||Down||Amu Darya||Syr Darya|
|Small rivers (g/m³)||475||431||547||500||449||506|
|Used drainage water (g/m³)||1927||1645||1980||-||1998||1053|
|Internal use (g/m³)||3131||2220||3493||3099||3501||2799|
|Total water supply (g/m³)||710||483||717||989||647||807|
|Disposal to Aral Sea (g/m³)||1142||-||-||1142||976||1650|
|Drain/irrigation salinity ratio||446||425||580||307||551||334|
In the SyrDarya basin, the average salinity of the river water is about 50 percent. This is about 20 percent higher then in the AmuDarya basin. Therefore the conditions for irrigated agriculture in the SyrDarya basin, especially in the lower reaches, are less favourable than those in the AmuDarya basin, especially in the upper and middle reaches. This is because more return flow of effluent occurs in the SyrDarya basin than in the AmuDarya basin, where comparatively more saline effluent is evacuated to evaporation ponds.
The salinity of the drainage effluent is about 30 percent higher in the AmuDarya basin than in the SyrDarya basin. This could indicate a higher irrigation and leaching efficiency in the SyrDarya basin, and more salt mobilisation by the subsurface drainage system in the AmuDarya basin. The highest salt mobilisation is in the middle reaches of the AmuDarya basin.
During last years many industrial enterprises stopped functioning, that's why industrial sewage into reservoirs is reduced considerably. However, wear out of canalisation and refining stations, practically complete lack of reconstruction or construction of new ones aggravate water quality deterioration of surface reservoirs. Volume of pollution coming into water from atmosphere, residual chemicals, pouring from irrigated fields, uncontrolled growth of farms on the banks of the rivers, dung sewage wash off, pollution from gardening co-operatives, located on the banks of the rivers lead to slow degradation of surface water quality.