Comment: Unsustainable water practices, drought and climate change are causing a water crisis across the US Southwest. Solving this problem will require major intervention to help farmers use less water – and cities can help.
“Are you running out of water?” is the first question people ask when they find out I’m from Arizona. The answer is that some people have already done this, others will soon, and without dramatic changes it will get much worse.
Unsustainable water practices, drought and climate change are causing this crisis across the US Southwest. States are withdrawing less water from the Colorado River, which supplies water to 40 million people. But water levels in Lake Mead and Lake Powell, the river’s two largest reservoirs, have dropped so low so rapidly that there is a serious risk that one or both will soon encounter a “dead pool,” a level at which no water will flow flows from the dams.
On June 14, 2022, US Bureau of Reclamation Commissioner Camille Calimlim Touton warned Congress that the seven Colorado River Basin states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming — were rerouting their Colorado River diversions 2 million to 4 million acre feet by 2022. One acre foot is enough water to cover one acre of land about the size of a soccer field with one foot of water—roughly 325,000 gallons. If the states don’t come up with a plan by August 2022, Touton can do it for them.
To meet the Touton target, states must focus on the region’s largest water consumer: agriculture. Farmers use 80% of the water consumed in the Colorado River Basin. As a longtime analyst of Western water policy, I believe that solving this crisis will require comprehensive intervention to help farmers use less water.
Lawn in the desert
It is no exaggeration to describe the water shortage in the Southwest as a crisis. Falling river levels affect hydroelectric power generation, affecting the power supply to millions of people. Farmers lay down fields and use less water for their crops. This in turn jeopardizes food production, which has already been globally affected by the war in Ukraine. Drought conditions could wipe out endangered species, particularly salmon.
There is something deeply unsettling about the lush green landscape of Southern California, a desert transformed by the power of water. The average annual rainfall at Los Angeles International Airport from 1944 to 2020 was 11.72 inches (30 centimeters). That’s not much more than Tucson, Arizona, in the middle of the Sonoran Desert, gets.
Now, however, western states are imposing unprecedented restrictions on water use. On June 1, 2022, the Metropolitan Water District, wholesaler for 20 million Southern Californians, urgently requested a 35% reduction in water use. In response, the Los Angeles Department of Water and Energy limits residents to watering their lawns twice a week for eight minutes per session. Other providers only allow weekly watering.
The California Water Resources Control Board has ordered many farmers and cities in the San Francisco Bay Area to stop diverting water from the San Joaquin River system. Golf course operators are under significant pressure to reduce water use.
Focus on watering
Still, agriculture uses far more water than lawns and golf courses. In 2017, US farmers irrigated about 58 million acres (23 million hectares) of farmland, nearly two-thirds of it in the west.
In recent decades, western farmers have changed their irrigation practices significantly. Many have switched from flood systems that literally flood fields to pressure systems. Typically these are central pivots that apply water from sprinklers connected to a large arm that moves slowly around a core, creating those large, usually green, circles that plane passengers in the west can see. This shift reduces water losses through evaporation, seepage into the soil, and runoff.
In 2012, US farmers used pressure systems on 72% of their fields, up from 37% in 1984. That leaves 28%, or 20 million acres (8 million hectares), that will be flooded.
And center-pivot systems aren’t as efficient as drip or micro-irrigation, which deliver water directly to the plants’ root zone through hoses embedded in the soil. Drip irrigation delivers water slowly, reducing runoff and evaporation. Micro-irrigation systems use 20% to 50% less water than traditional sprinkler systems.
Balancing rural and urban needs
Helping farmers transition to high-efficiency irrigation systems would benefit the entire Southwest. I propose a two-pronged approach.
First, Congress would provide funds to the US Department of Agriculture to offer farmers more generous financial incentives to switch to micro-irrigation systems. The Infrastructure Act of 2021 includes $8.3 billion to help western states adapt to drought and climate change. I believe this financial aid, with support from the Federal Bureau of Reclamation and the USDA, could persuade millions of American farmers to take the plunge.
Second, to expand the federal program, state, municipal and local interests, including government agencies and private companies, would create funds to meet the entire cost of converting farms to micro-irrigation. The way I envision it, cities could offer to cover 100% of the purchase and installation costs of microsystems in exchange for a percentage of the water farmers would save by switching.
A free program for farmers would be far more attractive than existing federal programs. In my view, locally funded programs managed in partnership with farming communities could redistribute a lot of water in a short amount of time. This could be done either through a formal transfer of water rights or through short- or medium-term leases with farmers who retain water rights.
In the past, farmers have been rightfully suspicious when city officials have arrived with proposals to purchase farm water. All too often, such transfers have triggered economic death spirals for rural communities. But it doesn’t have to be that way.
Since farmers use about 80% of western water, while residential, commercial, and industrial use less than 10%, I believe that reducing agricultural use by a few percentage points would meet municipal and industrial water needs. If farmers can achieve that reduction thanks to the increased efficiencies of micro-irrigation systems — paid for by cities — farmers could grow as much product as they do now with a little less water.
This transition could bring economic and technical challenges. For example, most farms would likely abandon or reduce production of low-value crops such as alfalfa, which could affect feed prices. And one downside to drip irrigation systems is that ground squirrels like to chew on the plastic hoses, so farmers would need an animal control program.
Nonetheless, I see voluntary, compensated water transfers as a strategy that would protect the long-term viability of rural communities and keep faucets running in western cities. Restrictions on watering lawns will not solve the West’s water crisis.
This article was republished by The Conversation under a Creative Commons license. Read the original article.
Robert Glennon is one of the nation’s pre-eminent experts on water policy and law. He is Regents Professor Emeritus and Morris K. Udall Professor of Law & Public Policy Emeritus at the University of Arizona.