Agricultural Drainage Water Reuse

With growing demands on freshwater resources and increasing signs of climate change, pressure is mounting on the agriculture sector so as to continue producing more food and fiber, with less water, to satisfy current and future demands for food security.

Agricultural drainage water reuse, particularly in large-scale irrigation countries, offers an opportunity to reduce the gap between water supply and demand in agriculture and increase the overall water use efficiency, hence preserve fresh water for higher-value uses.

Investment in drainage water reuse represents a low-cost water management opportunity with high economic return. However, environmental risks exist due to the high contents of salts, residues of agro-chemicals and sometimes other biological and toxic pollutants. Therefore, agricultural water reuse has to be managed carefully to safeguard the environment and minimize the negative impacts on water, land, crops and the ecosystem. Similar to fresh water, policies to protect agricultural drainage water from pollution should be in place.

It is recommended to support drainage water reuse in terms of improved legal and institutional arrangements; financial and economic organizations; technology and infrastructure; planning and management tools, as well as knowledge development.