Hogging the water

Agriculture consumes 80% of water in the US, and 56% of that water is for crops to feed livestock. On top of that, livestock themselves drink huge quantities of water — 34 trillion gallons a year in the US. A cow drinks about 20 gallons of water per day.

About 1,000 litres of water are required to produce 1 kilogram (kg) of cereal grain, but 43,000 litres to produce 1 kg of beef. There is more nutritional value in beef than cereal per kg, but certainly not 43 times as much.^​1​

Another study showed that on average, it took 0.5 cubic metres of water to produce 1,000 kilocalories from plant-based food, and 4 cu m of water to generate that amount from beef – eight times as much.^​2​

Grazing animals may find part of their own food requirements, but they still need water.  Aside from issues surrounding water scarcity, fossil fuels must be extracted and burned to treat and transport water for livestock and the crops grown to feed them.