Irrigation in the Aral Sea Basin

Abstract

Irrigation is highly developed in the Aral Sea basin. In 2010, irrigation networks covered 8.1 million ha here and accounted for 84 % of all water withdrawals. Irrigation as a highly consumptive user of water is the primary cause of the desiccation of the Aral Sea as it has severely diminished the inflow to the Aral from the Amu Darya and Syr Darya. Irrigation has a long history in the Aral Sea Basin dating back at least 3,000 years. During the Soviet era, irrigation was greatly expanded and water withdrawals for it increased considerably, primarily to grow more cotton. In the post-Soviet period, the area irrigated only increased slightly while water withdrawals for it declined somewhat. The latter has been primarily due to shrinkage of the area planted to high water use crops such as rice and cotton and not to the introduction of more efficient irrigation techniques on a substantial scale. Irrigation systems in the Aral Sea Basin since collapse of the USSR have badly deteriorated owing to lack of proper maintenance of them and insufficient investment in them. And the problems of soil salinization and water logging continue to worsen. There is certainly much that could be done to improve irrigation and use less water for it. This in turn could allow much more water to be supplied to the Aral Sea. But significant improvement of irrigation will require much greater effort and investment along with institutional reforms.