The Water Footprint of Foods
“California is experiencing one of its driest years in the past half millennium. It also happens to be the country’s leading dairy supplier. With profits surpassing $7 billion in 2012, the California dairy industry is far and away the most valuable sector of the state’s enormous agricultural bounty. Unfortunately…dairy products use a whole lot of water…According to a 2012 study in the journal Ecosystems, 
University of California-Davis plant scientist, Dan Putnam, used a University of Wisconsin study to estimate the amount of milk an acre of alfalfa hay can produce in a year. His calculations, combined with the California Dept. of Water Resources’ statistics on the yield of an acre of alfalfa, demonstrate the water footprint of a gallon of milk: It takes 683 gallons of water to grow 6 pounds of alfalfa hay to feed one cow to produce 1 gallon of milk.
Here are some other top water users: yearly use is in billions of gallons:
Alfalfa, 1,700 gallons
Almonds and pistachios, 1,300 gallons
Rice, 900 gallons
Orchards, 800 gallons
Corn, 775 gallons
Grapes, 600 gallons
Cotton, 380 gallons
Tomatoes, 300 gallons
Onions and garlic, 150 gallons
Potatoes, 50 gallons
Water use to produce milk products compared with nut and bean “milks”:
One stick of butter, 109 gallons
One Greek yogurt, 90 gallons
One scoop of ice cream, 42 gallons
Two slices of cheese: 40 gallons
One yogurt, 35 gallons
One glass of milk, 30 gallons
One glass of almond milk, 23 gallons
One glass of soymilk: 9 gallons
The water footprint of meat products is even bigger than that of dairy. It takes 425 gallons of water to produce a 4-ounce serving of beef in the US. The same size serving of pork takes 164 gallons of water; for chicken, 66 gallons.
The same New York Times piece suggests that replacing half of the animal products in your diet with plant-based foods reduces our food-related water footprint by 30%. Going vegetarian reduces it by 60%. (Just think how going vegan, even part-time, reduces our water footprint.)
Source: “It Takes HOW Much Water to Make Greek Yogurt?!” by Julia Lurie and Alex Park, http:..m.motherjones.com/environment/2014/03/California-water-suck