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Spending water to produce meat

Raising animals for meat requires much more water than growing plants of equal nutrition. Meat-eating has a larger “water footprint,” scientists say.

Researchers in the Netherlands have published a study showing the true cost of animal products globally – from a water perspective. The study was published online on January 24, 2012 in the journal Ecosystems by Arjen Y. Hoekstra of the University of Twente and his team. It shows that increased global meat production is a potentially major environmental problem, because raising animals requires a lot more water than growing plant products of equal nutrition. Because water resources vary around the globe due to differences in rainfall and ground water supplies, where the water is coming from is a very important aspect of the total water cost, or water footprint of meat, these scientists say.

Image courtesy of: Pima Community College

The global demand for meat and animal products is skyrocketing as human population grows, and as wealth increases in rapidly developing nations like India and China. Global meat consumption doubled between 1980-2004 and will probably double again by 2050. This new paper from Hoekstra’s group, the Water Footprint Network gives a thorough report on the global water demand of raising animals, and categorizes water use into “green” (rainwater), “blue” (surface and groundwater), and “gray” (water needed to dilute pollutants and wastewater treatment).

Green water is the largest part of the water footprint for all countries surveyed. However, more industrialized and concentrated animal farming operations rely heavily on blue and gray water compared to traditional production systems where animals graze or are “free-range”. The heavy reliance on blue water in industrial animal farming is due to the need for producing concentrated animal feed that is water costly, and a large amount of gray water is needed to dispose of large amounts of animal wastes.

Because increased demand for animal products will likely lead to greater industrialization of animal farming, the authors speculate that there will be a significantly higher blue and gray water footprint (water per unit of meat consumed) in the coming decades, with the potential to stress municipal and crop production water demands.

Bottom Line: Producing animal products requires a lot more water than producing plant crops of equal nutritional value, according to a new study of meat production’s water footprint published January 24, 2012 in the journal Ecosystems by Arjen Y. Hoekstra of University of Twente in the Netherlands and his team. These researchers say that policies aimed at supporting sustainable agriculture need to address not only the amount, but type of water being used.

Benjamin D. Duval