Thirsty cities seek to grow as farmers increase efficiency
YUMA, Ariz. (AP) -- The water in the Colorado River could fill the needs of all the homes and offices in Phoenix, Tucson, Las Vegas and much of Southern California, but much of it irrigates vast fields of wheat, alfalfa, cotton and vegetables.
That has painted a target on farms as urban water managers search for sources to meet future demands.
However, water experts say the issue has grown more complicated than transferring water from one user to another. The conflicts have evolved from cities versus farmers to more nuanced sustainability issues, such as trading future urban water supplies for locally grown food.
"We don't want to get into a situation of saying 'My use is better than yours,'" said Tom Davis, general manager of the Yuma County Water Users Association. "But there needs to be a better way than just whoever has the most money gets the most water."
More than a billion gallons a day go to irrigating fields. The fields soak up 70 percent of the water supply, but crops yield about 1 percent of Arizona's annual economic output.
Farmers can take so much water because they staked their claim first. Most of the irrigation districts in Yuma hold rights to the Colorado River that predate Hoover Dam, which means if the river starts to run dry, the farmers get their share before anyone else. They can lease water to other users while keeping the long-term rights.
Together, the largest water districts in the Yuma area can divert more than 750,000 acre-feet of water from the Colorado each year. An acre-foot is 325,851 gallons, enough to supply two typical households for a year.
Metropolitan Las Vegas, with a population of more than 2 million, can draw just 300,000 acre-feet a year.
Farmers say they manage their resources carefully, more so, they argue, than the cities.
"The real end user of that water isn't the farmer, it's the guy who buys the lettuce or the cauliflower," Davis said.
"If this basic industry is reduced because cities want their golf courses and their lawns, how long before we can't feed our own country?" he said.
Urban areas have long viewed agricultural water as a backup supply during a drought or other shortage, but farmers fear some cities want the water as a permanent supply for future growth. The shift has already happened in Phoenix, where the Salt River was once lined with citrus groves and cotton fields. As recently as 1965, 80 percent of the water delivered by Salt River Project was used by agriculture. Today, that number is just 15 percent.
Farmers and others argue that growing food is a more sustainable use of water because locally grown produce reduces the need to import fruit and vegetables, which shrinks fuel consumption and adds certainty to the food supply.
"We can start out asking, 'What food do we need to nourish Arizona's population?' and 'What do we do to meet Arizona's food security?'" said Gary Nabhan, a research social scientist at the University of Arizona's Southwest Center. "I think the most water- and energy-efficient way to do that is dedicating our farmland to low-water food crops."
Those would be vegetables and some grains that can grow on drip irrigation systems and require less water than alfalfa, cotton or some kinds of corn.
Nabhan said Arizona has grown under the false impression that retiring farmland in favor of cities will conserve water.
"The farmers have already reduced water use for reasons of economics and water restrictions," he said. "We've already seen greater efficiency without a very straightforward program. And yet we've put tons of money into urban water programs and we haven't made that great a gain."
Most water experts say it's likely that cities and states will look for ways of moving at least some water from farms to urban uses.
Rick Sellers farms about 4,000 acres between Yuma and the U.S.-Mexico border. He makes his best money during the winter, when he grows lettuce, cauliflower, broccoli and fennel.
He admits that the vegetables take a lot of water. "But we manage the heck out of it. We try to stretch it as far as we can," he said.
Sellers uses sprinkler pipes across many of his fields instead of running water down ditches, and he spent $48,000 this year to line a section of dirt ditch with concrete. He employs a small army of irrigators to make sure crops get only the water needed.
"Frankly, I think we're about as efficient as we're going to be," he said.