Joint Use of Surface Water and Ground Water of the Fergana Valley (Central Asia) as Way of Overcoming of Water Deficiency

The Fergana Valley shared by Kyrgyzstan, Tajikistan, Uzbekistan. Socio-political situation in the Valley is characterized by acute land and water resources deficit and their exhaustion, a number of difficult environmental problems, etc. Water shortage is a sharp problem for the Valley, and it becomes complicated in dry years. Per separate years and seasons the sharp water deficiency is observed in the Uzbek part of the Valley. For example, many crops were lost in 2006 because a water shortage during growing season (April - September). In particular, in 2006 the water availability for irrigation has made: April - 15.4%, May - 45.5%, June - 46.7%. At the same time, rather low salinity of groundwater (0.5-1.5 g/l) in the top horizons of it allows to lower water deficiency at their use for irrigation. Agrees by expert estimations, the volumes of groundwater for possible use is estimated in 3-4 cubic km., which can be withdrawn without damage to surface water and ecological restrictions. Idea and project on joint use of surface and groundwater is offered for local level of water users. Realization of idea will allow receive the following effects: 1. Ecological: reduction of groundwater drain of high salinity to river systems. As a rule, high salinity water from the bottom layers of groundwater deposit are squeezed out in the river and pollute its water; 2. Economic: sharp increase of coefficient of useful water use: it will be close to 1.0 as a consequence of reduction of way from water source to field, while efficiency of irrigation systems (canals etc.) makes 0.55-0.63. Economy of used water resources will make about 40 %; 3. Social effect will be reflected in reduction of water deficiency's risk, accordingly - in increase of access to water of local population and increase of productivity of private enterprises.