Farm Water Management Lessons from the Desert

From National Geographic, Published on 27 September 2015

In this patchwork quilt of irrigated green farms tucked into a vast expanse of desert, cacti and mesquite, it seems improbable that water-loving vegetables could be sustainably produced on a large scale.

Yet Arizona is second only to California as the country’s largest grower of lettuce, spinach, melon and other such crops. Year-round warm temperatures and decades of smart water planning have earned the state its place in the market.

Unlike California, however, Arizona is not currently facing a water crisis, even though it too is enduring prolonged drought. “We’ve created resiliency in our water supply, ” said Arizona Department of Water Resources Director Thomas Buschatzke at a recent drought panel.

Large-scale vegetable production in the desert may be a challenge over the longer term, but in the short to medium term Arizona is faring far better than California at managing its scarce water resources.

Minimal rainfall as a perennial condition has forced Arizonians to learn how to grow food on a lean water budget. The state’s landmark 1980 Groundwater Management Act and other water policies have incentivized Arizona farmers to develop some of the country’s most water-efficient farming practices, according to a recent study .

Perhaps even more important, tight water budgets have bred a water-first mindset among farmers. Robert Knorr, a fourth generation farmer who grows jalapeno peppers, melons, wheat, corn, sunflowers and potatoes on his 3,000-acre Maricopa farm, exemplifies this attitude.

“We track water like we do financial statements, down to the acre inch that’s applied, where it’s applied, how it’s applied and when it’s applied,” he said on a recent visit to his farm.

Knorr grew up outside of Minot, ND, where the farming season is short and wheat is king. Arizona’s longer growing season, crop diversity and stable water supply drew him to the state in the mid 90s.

Though he started growing wheat and cotton, he quickly moved into jalapenos. Salsa sales were exploding in the U.S., and food processors like Pace were searching for a year round supply of fresh peppers to fill the gap left by California’s and Mexico’s growing seasons.

Today, the entrepreneurial Knorr is one of a handful of major growers in the United States supplying jalapeno peppers to major food companies like Hormel, Pepsi-Co and Campbell’s Soup, which owns Pace Salsa.

Like many farmers in Central Arizona, Knorr gets his irrigation water from the Colorado River through the Central Arizona Project, a 336-mile diversion canal. He calls it the “lifeline to Arizona agriculture.”

Groundwater over pumping in Central Arizona during the 1960s and 70s led to the state’s passage of the Groundwater Management Act, and in exchange for tighter restrictions on well water, the state made Colorado River water available to farmers at subsidized rates.

Knorr receives four and a half acre-feet of (or roughly 1.5 million gallons) per year and he metes out every drop judiciously. Over the past decade, he’s gradually shifted one-third of his acres from furrow (a form of flood) irrigation to highly efficient subsurface drip irrigation.

“In the past, we’d use 10 to 15 acre feet of water per acre on the high value crops like jalapenos.” he said. “Today we use less than eight acre feet for the entire harvest.” Switching to subsurface drip irrigation has also cut his fertilizer costs in half while increasing his productivity 40 percent.

Brian Betcher, who oversees the Maricopa-Stanfield Irrigation District, says that Knorr’s attention to water conservation is typical of farmers in his district. Others have adopted basin level irrigation, which uses precision laser to level farm fields, and can improve furrow irrigation efficiency up to 85-90 percent.

“Farmers have to dance and parry with all the resource circumstances and it makes them pretty smart, or if they’re not they’ll have to get out of the business and do something else,” Betcher said in a phone interview.

In stark contrast from California, which just last year passed first-ever rules for groundwater pumping, the Maricopa-Stanfield District not only restricts, but physically controls, the groundwater wells used by farmers. Farmers like the system because it helps ensure they’ll have a guaranteed source of water, says Betcher.

“If we have a well go down, we either switch to another one or use more Colorado River water. In the old days, if a well went down it could take three months to repair and you could lose the crop.”

Energy savings are another benefit as power providers can more efficiently manage the flow of energy to one centralized source than to hundreds of individual farms.

Need for Finance

While many agree that the right policies in Arizona have incentivized farm water conservation practices, financing is a limiting factor.

Drip irrigation costs Knorr roughly $2,000 to $2,500 per acre. Basin level irrigation costs may be about half of drip, thought Betcher.

Without the help of 50/50 cost-sharing grants he receives from the conservation district EQIP program, Knorr says he would not be able to invest in the system. In fact, he’d like to convert all of his acres to drip irrigation, but the conversion will take time because of limited funding.

Betcher adds that, “even a 50/50 cost share won’t make the numbers work out for some of these guys when the farm economy is poor.”

Other financial support, such as from buyers, could be helpful, and there are successful models for buyer support for their growers.

“I’d love anyone to help me with water conservation,” agrees Knorr.

Water Challenges Ahead

In the years ahead, Arizona farmers will need to further tighten their belts.

“We’re looking at a 900,000 to 3 million acre foot supply demand imbalance in the next 25 to 100 years,” Buschatzke says.

In fact, Arizona dodged a bullet in August when the U.S. Interior Department declared that Lake Mead’s elevation was sufficient to forestall cuts in water allocations to the seven states sharing Colorado River water. Had Lake Mead’s level dropped three feet lower, Arizona would have lost about 11 percent of its Colorado River allocation, and the brunt of that loss would have fallen on farmers.

Eventually, Arizona will face cutbacks to its Colorado River allocation. Water experts predict a 52 percent probability of that event occurring in 2018.

While Betcher predicts that over the longer term, irrigated acreage will decrease in Central Arizona, he thinks a public policy approach could find the right mix of Colorado River water and groundwater to ensure a certain acreage of farming.

Further to the southwest, in Arizona’s top vegetable producing region, Yuma, farmers are already experimenting with rotational fallowing.

“We’re on the cusp of figuring out how to find some financial ways to help farmers convert from alfalfa and cotton because at some point you will need a crop with a lower consumptive use,” says Steve Olson, a state water expert who works with farmers in Yuma.

Knorr is well aware that his future water allotments are likely to be smaller while his costs get higher. “We evaluate from a big picture farm plan: how much land do we have, what return can we get, but it’s going to come down to how much water,” he says.

Suggested additional reading about water management:
Golden State, golden lawn? Xeriscaping: A Water Management Practice
Why California’s Drought is a Global Issue
Water at the Heart of the Global Resource Nexus