Does food trade save water ? The potential role of food trade in water scarcity mitigation

With increasing global water shortages and awareness of the environmental impacts associated with irrigation, the concept of trading in virtual water (the amount of water used to produce an agricultural commodity) is receiving attention. Instead of striving for food self-sufficiency, water short countries should import food from water abundant countries, because this has a large potential to alleviate water scarcity.

Food trade reduces water use at two levels. At a national level, a country reduces water use by importing food rather than producing it. At global level, trade reduces water use because, at present, production in exporting countries is more water efficient than in importing countries. In particular, cereals are mainly grown under rainfed conditions in the USA, Canada, Argentina, Australia and the European Union.

The Comprehensive Assessment of Water Management in Agriculture presented in this policy brief quantifies global virtual water flows in the past from 1981 to 2000 and in the future in 2025.

Trade in food and virtual water results in real water savings when the water saved can be reallocated to other uses, such as environmental uses. Under rainfed conditions, rainwater usually cannot be allocated to other uses besides alternative rainfed crops, but reductions in irrigation water depletion result in real water savings.

Food trade as an answer to water shortages is appealing, and has a large potential to minimising investment in irrigation infrastructure, but firmly established political, social and economic interests in agricultural trade limits the potential of this option.