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Afghanistan

How the water flows: A typology of irrigation systems in Afghanistan

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Executive Summary

This paper develops and presents a typology of irrigation systems in Afghanistan. It is intended to enhance knowledge of irrigation methods and management with the aim of improving system performance and productivity. It is also intended to provide those involved in irrigation r e h a b i l i tat i o n and natural resources management with a better understanding of the link between irrigation systems and livelihood sustainability. The importance of irrigated agriculture is undeniable since it is the mainstay of food security and income for the majority of the rural population, accounting for more than 70 percent of total crop production.

For the past 30 years, the rural sector has been severely impacted by war and civil unrest. The structures of irrigation systems have been damaged directly and sometimes deliberately. While many rehabilitation efforts by necessity have been emergency assistance, long-term strategies to improve the performance and reliability of irrigation systems are also required.

It is important to note that a great deal of information, resources and institutional capacity for accurate monitoring and reporting on natural resources were lost during the years of conflict. While significant efforts are underway to fill the information void, many inaccuracies and gaps remain.

National overview

The topography and climate of Afghanistan are the principal influences on the development of the type, range and distribution of irrigation systems. With predominantly dry continental climate, most of the country's cultivable area receives low or negligible rainfall during the irrigation season. Most annual precipitation occurs at high elevations in the Hindu Kush mountain range. The quantity, timing and distribution of precipitation chiefly determine water availability for irrigation.

Along with land allocation, the occurrence and distribution of water resources primarily determine the type and location of irrigation systems in the country. Average annual volume is estimated at 95 billion m3 of which 88 percent is surface water and 12 percent is groundwater.

While Afghanistan has five major river basins, nearly 60 percent of water resources come from the Amu Darya in the north. Surface water flows peak in the spring and early summer following snowmelt. The timing and duration of these flows presents both an opportunity to harvest water and a challenge due to the risk of floods.

Afghanistan's groundwater resources lie in a number of aquifers from which water has traditionally been extracted through karez an wells. To date, however, there appears to be little detailed research conducted on these water resources.

The cultivable area of Afghanistan is estimated to be 7.7 million ha, which is roughly 12 percent of the country's area. A land use survey from the 1990s estimated 3.2 million ha was irrigated of which 48 percent was intensively irrigated and 52 percent was intermittently irrigated with one or more crops. Of the five river basins, the Helmand supports the largest irrigated area (44 percent) in the country.