The American West faces its fifteenth year of low rainfall, sparse snowpack, and warming temperatures in what climatologists believe is only the beginning of a climate-change-induced megadrought that may last a century or more. Major cities across California recorded historically low precipitation levels in the last two years. At least 78 percent of the state is now categorized as suffering “extreme drought,” including the state’s Central Valley, the nation’s most productive agricultural region. California hasn’t been this dry in 1,200 years.

We tend to blame the exurban sprawl dweller for water waste. The profligate of the cul-de-sac, he obsesses over car washes, floods the Kentucky bluegrass on his lawn, tops off his swimming pool, takes the kids to water parks, and tees off at green golf courses tended among cacti. He is the wrong object of our ire, however. Personal and industrial consumption for drinking, washing, flushing, watering the lawn, detailing the car, and cooling nuclear plants, accounts for less than 10 percent of water use in the eleven arid states of the West.

We’d do better to look at what we eat when casting about for villains of the water drama. Food production consumes more fresh water than any other activity in the United States. “Within agriculture in the West, the thirstiest commodity is the cow,” says George Wuerthner, an ecologist at the Foundation for Deep Ecology, who has studied the livestock industry. Humans drink about a gallon of water a day; cows, upwards of 23 gallons. The alfalfa, hay, and pasturage raised to feed livestock in California account for approximately half of the water used in the state, with alfalfa representing the highest-acreage crop. In parts of Montana, as much as 90 percent of irrigated land is operated solely for the production of livestock feed; 90 percent of Nevada’s cropland is dedicated to raising hay. Half of Idaho’s three million acres of irrigated farmland grows forage and feed exclusively for cattle, and livestock production represents 60 percent of the state’s water use. In Utah, cows are the top agricultural product, and three-fifths of the state’s cropland is planted with hay. All told, alfalfa and hay production in the West requires more than ten times the water used by the region’s cities and industries combined, according to some estimates. Researchers at Cornell University concluded that producing one kilogram of animal protein requires about 100 times more water than producing one kilogram of grain protein. It is a staggeringly inefficient food system.

One obvious and immediate solution to the western water crisis would be to curtail the waste of the livestock industry. The logical start to this process would be to target its least important sector: public lands ranching. The grazing of cattle and sheep on hundreds of millions of acres of federally managed land has been a fact of western rural life for over 100 years. It is considered an almost sacred profession. Yet its impact on the economy is actually quite small. According to University of Montana economist Thomas Power, public lands ranching produces just $1 out of every $2,500 in income and one out of every 2,000 jobs. Of concern to the steak lover: If this form of ranching ceased to exist tomorrow, the effect on the price and availability of beef would be negligible.

Grazing cattle and sheep in this arid landscape is the single most important cause of erosion and desertification on a public domain whose trees, rich soil, and grasslands function as ecosystem watersheds. “Livestock production, along with its coddled baby sibling, public lands ranching,” says Jon Marvel, founder of the Idaho nonprofit Western Watersheds Project (WWP), “is responsible for the largest single human use, degradation, and pollution of public watersheds in the western United States.” Stockmen cause over 95 percent of all western public land “dewatering”—when streams go bone dry—by diverting the natural flow to water cattle or grow hay. According to Marvel, a single cow on public land can deposit over a ton of waste on the ground every month, with a high percentage of that waste seeping into surface water. A single cattle feedlot in Idaho, located a mile from the Snake River, produces more untreated solid and liquid waste every day than four cities the size of Denver. “Every stream on public lands grazed by livestock is polluted and shows a huge surge in E. coli bacterial contamination during the grazing season,” says Marvel. “No wonder we can’t drink the water.”