Agricultural Water Use How can we use less water to grow the produce needed in this country?

Here’s one effect of the drought in California and elsewhere: there’s been a lot of fascinating reporting on water use in commercial agriculture. And the amounts of water that go into some crops, and where those crops are headed, has created something of a controversy.

It comes as no surprise that much of the produce grown in the United States comes from California. Some 95% of all the broccoli, 92% of all the strawberries, 90% of all the tomatoes, and 99% of all the almonds grown in this country come from California. Here’s an informative graphic detailing these amounts as well as the amount of water that goes into their production (eg, it takes 5.4 gallons of water to grow a head of broccoli). While much of this produce is consumed in America, some of it, like almonds, are mostly exported (1.1 gallon of water to grow one almond, or 6.6 gallons to grow a handful of six almonds).

With its large population, you would expect that California’s towns and cities — its people — would use their fair share of the state’s water resources. Turns out, 80% of California’s water goes to agriculture. Its most heavily irrigated crop, the one using the most water, is alfalfa. Humans, of course, don’t eat alfalfa (though it does make a good herbal tea).

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That fact suggests that the biggest consumer of water is meat and dairy production. With beef requiring some 400 million gallons of water per ton of meat produced, experts are starting to question such heavy water expenditures. A recent study (PDF) from the University of Twente in the Netherlands confirms the water demands of meat, measured against the nutrition it provides (lots of protein) is astronomical compared to other crops:

Nearly one-third of the total water footprint of agriculture in the world is related to the production of animal products. The water footprint of any animal product is larger than the water footprint of crop products with equivalent nutritional value.The average water footprint per calorie for beef is 20 times larger than for cereals and starchy roots.

Vegetarians may jump on these figures to point out that the world’s limited water supplies can’t support the ever-increasing demand for beef. And some food experts are suggesting that we need to consider the environmental consequences of eating all that meat. Global meat production doubled between 1980 and 2004 and it continues to mushroom as emerging economies develop a middle class that is hungry for beef. And this directly affects agricultural water use in California. With beef requiring some 400 million gallons of water per ton of meat produced are we now required to come up with ways to raise beef without such a heavy dependence on water? Do we need to moderate our consumption of beef to save water?

We can’t see steak and hamburger lovers or the National Cattlemen’s Beef Association, a rather powerful lobbying force, getting behind any of this. But one thing Americans should know. As we said, alfalfa, grown on over a million acres in California, uses more water than any other crop. And much of the alfalfa grown in California isn’t fed to cattle in the U.S. but shipped to China. Turns out it’s cheaper to send a boat load of alfalfa to China than it is to ship it on trucks from the Imperial Valley, where it’s raised to the Central Valley where the cattle are. This New York Times article on agricultural water use in California suggests that we’re shipping 100 billion gallons of water a year to China in the form of alfalfa.

Outside of meat production, it’s being pointed out that raising crops in California, with its abundant sunshine and lack of water, may not be as good a business model as it was in year’s past. Some columnists have suggested that the real resource that’s been squandered in California is the soil. Establishing soil building programs could go along way, as any organic gardener can tell you, to reducing water use through better moisture retention (as well as reducing the need for expensive chemical fertilizers and pesticides). And California’s agricultural soil has been sadly neglected, even mistreated, for decades.

Soil building programs, certainly not a cure-all for water problems, are a long term process, and not necessarily cost-efficient in their early stages. But their eventual benefits would results in savings of both money and water. Of course, convincing business interests that long-term investment in a world of short-term profit is another problem, especially when the solution points to more smaller, independent farms and less corporate control. Thankfully, some groups are already working on this.