The Nile Delta covers an agricultural area of approximately 2.5 million ha, irrigated by a dense network of waterways, including 40,000 km of canals that branch off the Nile River and convey water to over 2 million farmers across several nested geographical scales and institutional levels. Conventional irrigation efficiency is low in average, but the intensity of water reuse in the delta drastically increases macro-level efficiency.
With a current population growth rate of 2.1%, concern over a growing dependency on food imports and the need to compensate for the loss of highly productive agricultural land associated with urbanization, the Egyptian Government has pursued a strategy of vertical expansion (i.e. intensification on existing cultivated lands) and horizontal expansion into the desert (‘New Lands’), which is predicated upon better management and water savings in the ‘Old Lands’.
Land and water management practices are closely linked to the way people work and interact, and to institutions in general, including sets of formal/informal rules and practices. These practices in turn determine the patterns of water circulation and use, both in terms of quantity and quality, and govern which sources of water are tapped; the efficiency of water use at different scales; the spatial distribution of shortages in supply; the magnitude of the different return flows; the amount of salts applied and removed from fields; the spatial and temporal variation in salt contents; and the suitability of drainage water for reuse.
The most salient characteristic of the delta, and the source of much complexity in managing land and water resources, is the interconnectedness between users and managers across a maze of waterways.