According to the UN, the population of Central Asia will increase from its current approximately 65 million people to a well over 90 million by the end of this century. Taking this increasing population into consideration, it is impossible to project development strategies without considering three key factors in meeting the demands of a growing population: water, food and energy. Societies will have to choose, for instance, between using land and fertilizer for food production or for bio-based or renewable energy production, and between using fresh water for energy production or for irrigating crops. Thus water, food and energy are inextricably linked and must be considered together as a system. Recently, tensions among the Central Asian countries over the use of water for energy and energy production have increased with the building of Rogun Dam on the Vakhsh River, a tributary of the Amu Darya River. The dam will provide upstream Tajikistan with hydropower, while downstream countries fear it could negatively impact their irrigated agriculture. Despite recent peer reviewed literature on water resources management in Amu Darya Basin, none to date have addressed the interconnection and mutual impacts within water-energy-food systems in face of constructing the Rogun Dam. We examine two potential operation modes of the dam: Energy Mode (ensuring Tajikistan's hydropower needs) and Irrigation Mode (ensuring water for agriculture downstream). Results show that the Energy Mode could ensure more than double Tajikistan's energy capacity, but would reduce water availability during the growing season, resulting in an average 37% decline in agricultural benefits in downstream countries. The Irrigation Mode could bring a surplus in agricultural benefits to Tajikistan and Uzbekistan in addition an increasing energy benefits in Tajikistan by two fold. However, energy production in the Irrigation Mode would be non-optimally distributed over the seasons resulting in the most of hydropower being produced during the growing season. Neither operation mode provides optimal benefits for all the countries, emphasizing how difficult it is to actually reach a win-win scenario across the water-energy-food security nexus in transboundary river basins. (C) 2016 Elsevier B.V. All rights reserved.
