Hugh Pickens DOT Com writes "Mames McWilliams writes in the NYT that with California experiencing one of its worst droughts on record, attention has naturally focused on the water required to grow popular foods such as walnuts, broccoli, lettuce, tomatoes, strawberries, almonds and grapes. 'Who knew, for example, that it took 5.4 gallons to produce a head of broccoli, or 3.3 gallons to grow a single tomato? This information about the water footprint of food products — that is, the amount of water required to produce them — is important to understand, especially for a state that dedicates about 80 percent of its water to agriculture.' But for those truly interested in lowering their water footprint, those numbers pale next to the water required to fatten livestock. Beef turns out to have an overall water footprint of roughly four million gallons per ton produced (PDF). By contrast, the water footprint for "sugar crops" like sugar beets is about 52,000 gallons per ton; for vegetables it's 85,000 gallons per ton; and for starchy roots it's about 102,200 gallons per ton.
There's also one single plant that's leading California's water consumption and it's one that's not generally cultivated for humans: alfalfa. Grown on over a million acres in California, alfalfa sucks up more water than any other crop in the state. And it has one primary destination: cattle. 'If Californians were eating all the beef they produced, one might write off alfalfa's water footprint as the cost of nurturing local food systems. But that's not what's happening. Californians are sending their alfalfa, and thus their water, to Asia.' Alfalfa growers are now exporting some 100 billion gallons of water a year from this drought-ridden region to the other side of the world in the form of alfalfa.
Beef eaters are already paying more. Water-starved ranches are devoid of natural grasses that cattle need to fatten up so ranchers have been buying supplemental feed at escalating prices or thinning their herds to stretch their feed dollars. But McWilliams says that in the case of agriculture and drought, there's a clear and accessible actions most citizens can take: Changing one's diet to replace 50 percent of animal products with edible plants like legumes, nuts and tubers results in a 30 percent reduction in an individual's food-related water footprint. Going vegetarian reduces that water footprint by almost 60 percent. 'It's seductive to think that we can continue along our carnivorous route, even in this era of climate instability. The environmental impact of cattle in California, however, reminds us how mistaken this idea is coming to seem.'"