Water stress, energy security and adaptation under changing climate: case study of Zeravshan river

Abstract:

Zeravshan a transboundary river in Central Asia is a snow-glacier fed river originating in Tajikistan that use only 4% of its resources, further flows to Uzbekistan who fully utilize river resources for irrigation. Such disparity in river usage causes Tajikistan to consider heavy investments in hydropower dams that will increase social and political tension between counterparts. Traditional irrigation under arid climate causes high rates of water losses in infiltration and evapotranspiration leading to land. Water stress analysis and water resources distribution under climate change and possible adaptation measures were investigated. The framework includes model to analyze available water resources and assessment of the basin efficiency including dam operation and irrigation demand, based on it adaptation measures were suggested. Comparison of the increasing irrigation efficiency in downstream to the 10% rate can decrease water requirements on early stages, however there are still large deficiency of the water resources in the peak irrigation season. Dam operation to benefit irrigation has positive impact while can't compensate the needs of energy in winter months. Cooperation of the both sides are required to address such changes in river flow as interest lies on opposite side. Increasing irrigation efficiency through using return marginal waters and salt tolerant crops under water stress were suggested. The plants were tested on several sites in the downstream of the river using mineralized return waters. The results suggest that using such plants can provide additional outcome for the local community while decreasing demand of the water resources and improving soil conditions. Combination of dam operation for energy production and increasing irrigation efficiency additionally by using return waters can provide a beneficial scenario for the region under future climate change. However, it will require strong political will to address energy swap to achieve nexus on water resources distribution between counterparts.