High-Tech Desert

The Great Decoupling of the West's Water

When Bart Fisher returned home from college in 1972, his family’s alfalfa fields outside Blythe in California’s southeastern desert produced 7 tons of alfalfa per acre. Today, the Fishers get 10 tons per acre from the same land. They do it with the same amount of water as a much younger Fisher and his family used four decades ago.

Growing water-use efficiency on farms like Fisher’s is one of the salient features of the evolution of agriculture in the developed world. Nowhere is this more apparent than in Palo Verde and the desert agricultural valleys of southwestern North America. These regions challenge two common narratives about water. The first is that we are blind to a looming disaster, sucking down water and ignoring a reality that will, in the words of Charles Bowden, “slap us in the face and we will have to snap alert. And this slap may come from our kitchen faucet….”1 It is the narrative most famously captured by the journalist Marc Reisner in his polemic Cadillac Desert,2 often read as a prediction that we are on a path toward “an apocalyptic collapse of western US society”.3

The second narrative, common among the technocrats who manage our water systems and the engineering enthusiasts who design them, is that inexorable growth of our population and economy inevitably means that we need more water – bigger dams, new desalination plants, new canals across the continent from wet to dry places, even icebergs towed from the arctic.4

Both narratives hang on a central premise – that more people and more economic activity inevitably means we’ll need more water. Recent experience in the United States southwest suggests both narratives need to be revisited.

In California, farm water use has declined by 40 percent since the 1980s, even as irrigated acreage has risen.6 Farmers like Fisher are growing more food with less water, with some of the saved water being shifted to cities, and modest steps are being made toward returning some of that water to the environment.

In cities too, water use is going down. Every one of the region’s major urban areas that once depended on unsustainable groundwater mining has turned the corner. Conservation and shifts to relatively more sustainable sources of supplies have led to aquifers beneath Los Angeles, the sunbelt of Central Arizona, and Las Vegas that have stabilized or in some cases are rising.5

Contrary to the narratives of apocalyptic doom or a need for ever-growing supply as a result of unsustainable water use, these communities have demonstrated an adaptive capacity that has allowed more people and economic activity using less water. This creates opportunity – to grow more food, to move water to cities, and to begin to reclaim some of the surplus for the environment.

But the needs of a growing population and the likelihood of increasing water scarcity caused by climate change still require coming to terms with our nation’s water use in agriculture. Agriculture continues to use the lion’s share of water taken out of the southwest’s aquifers and rivers for human use, four times as much water as the region’s cities.7 The growing efficiency seen in places like Fisher’s farm is therefore a central feature in understanding how to negotiate an uncertain future.


The Palo Verde Valley is harsh desert with an irrigated heart. Approaching from the east, Interstate 10 drops through a bluff to expose the Colorado River that the eclectic early twentieth-century art critic and travel writer John Van Dyke described as a boundary between wet and dry “drawn as with the sharp edge of a knife. Seen from the distant mountain tops the river moves between two long ribbons of green, and the borders are the gray and gold mesas of the desert.”8 Even in a wet climate, where there is no knife edge between brown and green, water is a landscape’s central characteristic. But in a desert like that of the Lower Colorado River, the impact is profound.

Like much of modern California, Blythe and the Palo Verde Valley as we now know them began their lives as a real estate investment scheme. San Francisco capitalist Thomas Blythe first hired an engineer named Oliver Calloway in the 1870s to drain a swamp and divert Colorado River water at a place called Black Point at the valley’s upstream end. In 1877 Blythe filed one of the oldest water rights claims on the Colorado River. The early ventures were a failure, and Blythe’s death left a legal tangle from which it took decades for valley agriculture to recover.9

But recover it did, and in a big way, because given the goals and policies of a growing nation, irrigated agriculture in this part of the world was inevitable. The combination of fertile desert soil, a year ‘round growing season, and abundant Colorado River water had by mid-twentieth century turned nearly every flat patch of river valley floor from the rugged Colorado River canyon country to the Sea of Cortez into farmland.

Farming has a deep history here. The native people who lived here before the arrival of the Europeans had long ago established a stable existence, practicing “flood recession farming”, planting along the river’s margin as its spring snowmelt peak receded.10 That was far too modest an endeavor for the boisterous newcomers of the young nation of the United States expanding westward from its European immigrant roots. To them, aridity seemed an act of defiance against the vanguard a sprawling empire.

French scholar Emile Boutmy in 1891 described the motivating forces behind the transition sweeping across the North American continent this way: “The striking and peculiar characteristic of American society is, that it is not so much a democracy as a huge commercial company for the discovery, cultivation, and capitalization of its enormous territory.”11

Pushing aside the native inhabitants, we were, wrote historian William Cronon, “bringing (the land) into the marketplace.”12 In the east and midwest, that meant felling timber and plowing prairie into farms. By the time the wave of new settlement reached the arid region west of North America’s hundredth meridian, the land could not be brought into the marketplace without heroic measures to manage the water. Or the lack of water.

With dam-building subsidies from a United States government bent on manifest destiny, each stretch of desert farm valley that could grabbed a portion of the Colorado River’s scarce water such that today the river almost never reaches the sea. Sixty miles up river from where Fisher and the other Palo Verde farmers take their water, Los Angeles dips its straw into the Colorado with a system of pipes, pumps, and canals that move water more than 200 miles to the growing cities of the coast. But the farms were here first. While the casinos of Las Vegas and the golf courses of Palm Springs and Phoenix stand as the icons of our modern desert civilization’s excesses, it is still agriculture that consumes 70 to 80 percent of the river’s water.

The history matters because it is what makes agriculture central to the communities that grew up here, even if Boutmy’s cultivation and capitalization of the territory has been elbowed aside by a twenty-first-century economy siphoning off water to coastal metropolises that dollar for dollar produce vastly more computer chips and software than food.

Agriculture today makes up just two percent California’s economy and provides four percent of its jobs.13 But the institutions we built to control and distribute the water and the rules meant to support farming, and communities and cultural traditions that grew up around it, were built for a very different world. It is not something easily unwound.


Fisher Ranch is famous for its honeydew melons, and melons are a lucrative, high-value crop for Palo Verde farmers. But in 2014 just 3 percent of the Palo Verde’s land was planted in melons. Alfalfa has always been the backbone of valley agriculture, taking up nearly two-thirds of the Palo Verde Irrigation District’s land in 2014. Alfalfa, used as feed for cattle and dairy cows, is what is often called a “low value crop”, by which we mean the dollars returned per acre of land and gallon of water are low relative to melons or the winter vegetables that now dominate the cash flow through desert agriculture. But with low labor and capital costs and a stable price compared to the ups and downs of the produce market, alfalfa to feed our desires for meat and dairy has always been a smart bet for desert farmers. Our love of hamburgers and ice cream ensures a reliable market.

Critics have long complained that it makes little sense to grow alfalfa in a desert, but such rhetoric ignores agronomic reality. With abundant sun and available water, places like Palo Verde are ideal places to grow alfalfa. In fact in terms of the environmental footprint of agriculture, the desert may be the best place to grow it.

Recall Fisher’s 10 ton per acre production. In a place like Idaho, another major alfalfa producing state facing issues with water scarcity, it takes twice as much land to produce the same amount of crop. The year ‘round growing season, allowing farming 12 months a year with no need to slow down in the winter, makes places like Palo Verde and the other nearby desert valleys by some measures ideal – if they can find the water to irrigate the land. “We don’t take winter or summers off,” explained Tina Shields, water manager for the nearby Imperial Irrigation District.

But in terms of dollars into a farmer’s bank account per acre of land and gallon of water use, alfalfa falls short of other crops. That is why thirsty metropolitan Southern California came calling on the Palo Verde Irrigation district in the 1990s looking to make a deal. The law allocating Colorado River water to the farm district made it impossible for wealthy, rapidly growing Southern California to simply take the water it needed, so the Metropolitan Water District of Southern California came offering money instead.

One of the features of modern water management that sometimes baffles economists is the relative value, in monetary terms, of water in different uses. With Metropolitan willing to pay farmers more for their water than they could make by using it to irrigate land, a simple free market economic transaction would have moved all the water to coastal cities. But Palo Verde’s negotiating team, led by Fisher, was not willing to allow a deal like that. Instead, they negotiated a lucrative arrangement under which some of the valley’s land can be fallowed in a year when Met needs water, paying farmers for the lost crop revenue.

That matched Met’s variable supply needs. While annual municipal water use is relatively stable, Met’s supply comes from three different sources – Colorado River Water, an aqueduct from Northern California, and groundwater and annual runoff within Southern California itself. When one of those supplies runs short, as has happened in recent years with deliveries from drought-plagued Northern California, Met needs to call more on its other sources, especially the Colorado River.

Flexibility in drawing on diverse sources of supply was critical to Met’s resilience, its adaptive capacity. But the leaders of the Palo Verde Irrigation District had some resilience goals of their own. To protect the long term viability of Palo Verde’s agricultural economic base, - their ability to retain, in the words of resilience scholars, the “basic structure and function” of their community - the program was capped. The most Palo Verde land that could be fallowed in any year was 28 percent. The rest of the valley would remain in production. The agreement struck a balance between the economic realities, the needs of growing city populations, and the desire of the desert farm community to retain its agricultural core. The result is a program that in 2015 fallowed 16 percent of Palo Verde’s least productive acres, moving the water that would have been used to irrigate it to Metropolitan.

The same basic story is being repeated again and again in Colorado River Basin agriculture – water moved from marginal lands to more economically valuable non-agricultural uses, while agricultural productivity on the land that remains continues to rise, either through shifts to more lucrative crops, or to more efficient irrigation techniques, or both.


California’s water books are not being balanced on the backs of agriculture alone. Alongside the striking increase in agricultural efficiency is a parallel phenomenon in Southern California’s cities.

Between 2004, the year the Palo Verde deal was signed, and 2015, total water use in the greater Los Angeles-San Diego metropolitan area declined 25 percent, even as the region’s population grew by 6 percent.14 Southern California has unique characteristics because of drought and water supply constraints that have made its water conservation performance better than many modern cities. But it is by no means unique. The decoupling between water use, population, and economic growth is even more stunning in the US municipal water use sector than it is in agriculture.

When it comes to water, the cities of the western United States get the most attention. Aridity and the struggle to overcome it have long defined the place and the stories we tell about it. Chinatown is the cinematic definition of Los Angeles, and Cadillac Desert the region’s non-fiction backdrop. But the pattern seen in L.A. and the region’s other arid cities is not merely a series of localized responses to geographic constraints. Rather, it is part of a pattern not only across the United States but through much of the developed world.

In the first decade of the twenty-first century, water use in the United States passed a remarkable milestone. For much of the life of the nation, water use rose with the growth of the nation’s population and its economy, both in per capita and absolute terms. Individually and collectively, our water use kept going up, contributing to a dominant cultural narrative of scarcity and risk. But beginning in the 1980s, the relationship between water, population, and the economy had begun to break down, with per capita municipal water use flattening out. Sometime between 2005 and 2010, the decline in per capita use became so rapid that total municipal water use in the United States began to decline, even as the nation’s population and economy continued to grow. 6,15

Government has played a central role. The Energy Policy Act of 1992, signed by Republican President George H.W. Bush in October of that year, imposed a federal mandate. After 1994, all toilets sold in the United States would have to meet a 1.6 gallon per flush standard, about half the norm at the time. It set standards for faucets, showerheads, and clothes and dish washing machines. That made water conservation automatic in each new building and whenever an old appliance was replaced, and established a base on which communities like Southern California could build, with rebates to replace old plumbing fixtures. Amy Vickers, the engineer and water conservation expert who wrote the 1992 legislation, has estimated that it results today in a savings of 20 gallons per person per day in the United States.

It is unclear how low the rich world’s municipal water use can go, but there is no reason to think that we are anywhere near the bottom. The World Health Organization offers a boundary – 25 gallons (100 liters) per person per day to meet basic indoor consumption and hygiene needs in a home with multiple water taps and continuous, 24/7 access to water. 28 That suggests a boundary condition well below the current US level of 89 gallons (340 liters) per person per day.6 It does not include outdoor water use for urban landscaping, which is critical in the long run because the water we put on our lawns and trees is generally fully consumed by evapotranspiration, and it does not include water used by businesses. So one should not expect water levels to drop that far.

But survey data and operational experience suggests the American public is willing to cut back far more than it is currently doing if needed.17 California learned this lesson well in recent years, with state-imposed mandatory municipal water use reductions leading to substantial savings beyond those already achieved by municipalities that had long been pursuing conservation measures.18 Per capita water use within the Metropolitan Water District of Southern California’s service area declined 14 percent from 2014 to 2015.26


While the nation’s water conservation success is undeniable, the environment continues to suffer from a century of decisions to remove water from rivers and aquifers for human use. In few places is that more apparent than the tail end of the Colorado River, which for its last 100 miles through Mexico to the Sea of Cortez is routinely dry save a modest amount of agriculture runoff from the farms of the Mexicali Valley.

What is left of the Colorado River as it flows through the deserts between Arizona and California is largely an agricultural water delivery system. Token wildlife refuge lands flank it at several points in its final run toward the sea. But when the river hits Morelos Dam on the Arizona-Baja border, humans divert its entire flow for farms, drying up its channel completely. It is, in the words of the late Philip Fradkin, a “river no more”.19

Even as efficiency gains in upstream farms and cities have increased the system’s reliability for human users, the environment remains a largely ignored water user. But water management decisions built atop growing efficiencies suggest opportunities to begin reversing that trend, including a major policy initiative in a most unlikely place.

Since 2003, agricultural water managers in the Imperial Valley have been quietly carrying out the Colorado River Basin’s largest experiment in shrinking agriculture’s footprint to provide water for a vast once-dry basin called the Salton Sea. Located northwest of the Imperial Irrigation District, the Salton Sea fills a sink below sea level, a shallow bowl created by a quirk in the region’s geology. It was a dry salt flat when early Imperial Valley irrigation works failed in 1905 in the midst of a flood, and the entire Colorado River took a hard right turn. For more than a year the river flowed into the sink instead of the ocean. Human engineering turned the river back to its original course, but agricultural runoff soon came into balance with desert evaporation and the Salton Sea became a permanent feature on the landscape.

The Salton Sea gets little attention in part because the environment at risk is ugly and smelly, not the sort of pristine high mountain trout stream or riparian valley whose aesthetics draw support from traditional environmental constituencies. But with the Colorado River desert’s wetlands all but gone, the Salton Sea has become one of the last toeholds left for migrating birds along the Pacific Flyway.

Its “unnatural” origins and dependence on agricultural runoff rather than a native river complicates the Salton Sea’s place in environmental politics. But the birds don’t care and the sea has become prime bird habitat, as waterfowl left with no natural delta moved to the sea instead.

The effort to protect the Salton Sea and its avian inhabitants demonstrates the potential and the perils of improving water use efficiency for the environment. Agricultural water management practices created the Sea. Changes to those practices have come to represent a major threat.

In the late 1990s and early 2000s, Los Angeles and San Diego came to Imperial farmers looking to buy water. California was living beyond its Colorado River water means, routinely taking 15 percent more than its minimum legal allotment under the rules that divide the water among seven states in the United States and two in Mexico. The rules gave surpluses to California, but a shifting climate and growing demands elsewhere had largely eaten up the surplus.

Within California, as supplies got tighter, the rules also ensured that the farmers in Imperial, Palo Verde, and elsewhere had first dibs on the remaining supplies, meaning any cuts would have to come from municipal water users in the San Diego-Los Angeles metropolitan areas. Faced with a threat to their supplies, the coastal cities of southern California came calling.

The lands of the Imperial Irrigation District are the largest single concentration of irrigated agriculture in the Colorado River Basin. Like Palo Verde, they are spread across a desert basin of rich soil left by millennia of Colorado River runoff, turned green by irrigation water now diverted from the river. Like much of the basin, alfalfa is the largest single crop. 20,21 And like Imperial’s desert neighbors in Blythe 80 miles to the east, the big money is in winter vegetables and melons.

The Southern California cities proposed to pay for irrigation system improvements, and pay farmers to fallow their land. The arrangement included canal lining to save water leaking from Imperial’s system into the sandy desert floor, and payments to farmers to tighten up the efficiency of water delivery on their farms through improvements like field leveling and installation of sprinkler systems to replace the traditional flood irrigation.

These are steps farmers frequently take on their own when water is expensive or scarce, but it requires significant capital investment. With Colorado River water abundant, Imperial farmers had little economic incentive to invest in efficiency on their own. Money from Los Angeles and San Diego changed the dynamic. The resulting arrangement was like the agreement already signed with Palo Verde, but on a grander scale.

But while the deal represented a win-win deal for the farmers and the cities, it presented an existential threat to the Salton Sea. Fallowing land or on-farm efficiency measures like the installation of drip irrigation would reduce the amount of runoff flowing into the Sea and risked upsetting the balance between inflow and evaporation. The decline of the sea also threatened to expose miles of shoreline, worsening the valley’s already poor air quality when wind kicked up potentially toxic dust left behind. So the deal included an important twist. Some of the conserved water, rather than being diverted to coastal cities, would be channeled directly into the Salton Sea.

To date, the largest agricultural-to-environmental water transfer in the Colorado River Basin has worked. Meanwhile left to their own devices to come up with the best approach in response to having less water to work with, Imperial’s farmers have prospered by reducing the acreage planted in low-value crops like alfalfa and shifting their resources to big dollar plantings like winter lettuce.29 And even as the acreage planted in alfalfa has declined, the increased productivity per acre has yielded a remarkable result. Total alfalfa tonnage produced in 2014 was essentially unchanged from the early 1970s.

The current agreement only runs to 2017, and local and state leaders are scrambling to come up with a permanent approach to protecting the Salton Sea. But the project to fallow farmland and use some of the saved water to preserve the Salton Sea provides an important case study in what it takes to exploit the potential environmental benefits offered by increased efficiency in desert agriculture.


As the effort to preserve the Salton Sea demonstrates, none of this is automatic or simple. Water efficiency in many situations can make farming more profitable. But that is no guarantee that water will be reallocated to cities or the environment. Much of the water saved in recent decades has stayed in agriculture, most notably in the expansion of the almond orchards of California’s Central Valley. Rather than moving water from low-value agriculture to cities, a big portion of the water has moved instead from low-value agriculture to higher-value agriculture.

The political and policy response to water scarcity has been equally important. Including water efficiency standards in the Energy Policy Act of 1992 had profound effects. Money from wealthy urbanized Southern California and complex government-to-government deals are what made the Palo Verde and Imperial water shifts possible.

But the direction of travel is clear and the opportunities for the environment are significant. Total agricultural water use in California peaked in 1980, and has been declining since. 6,13 In the face of water scarcity and higher costs, total California acreage devoted to rice, cotton, and alfalfa declined from 2.4 million acres in the 1992 Census of Agriculture to 1.8 million acres in the 2012 census. 26,27 In California just 21 percent of irrigated acreage used high efficiency targeted irrigation techniques like sprinklers and drip in 1985. By 2010, that had more than doubled to 45 percent. As a result, water use per irrigated acre in California has declined 43 percent since 1980.6

Yet what happened in Imperial demonstrates that reaping the benefit of agricultural efficiency for cities and the environment requires more than just market signals and better technology. It requires overt intervention to assure that society’s changing structure and values are matched with the opportunities provided by agricultural efficiency.

Unfortunately, a deeply entrenched water management paradigm continues to stand in the way. Consider the Los Angeles Department of Water and Power, one of the nation’s largest municipal water retailers, serving 4 million people. In a major 2005 planning effort, LADWP managers projected that over the coming decade their water demand would rise by 7 percent. In reality, it dropped by 18 percent. 14,31 Yet despite steady declines, the 2016 version of the agency’s draft water management plan again projects the trend that has resulted in a long term water use decline dating back to the 1990 will reverse itself, with water use rising again from their current low levels.

This pattern of overestimating future demand and underestimating consumer conservation is widespread, and is the major impediment to capturing the benefits that decoupling offers.

In the largest study of its kind ever done, the US Bureau of Reclamation in 2012 published a tome looking in detail at water and future demands, both municipal and agricultural, across the seven states that depend on water from the Colorado River Basin. The study drew headlines because of its projection of an inexorably rising need for more water for the region’s cities and farms.

The study’s conclusions and the underlying assumptions on which it is based have contributed to growing tensions between water users across the region as communities fear a future spent trying to cope with what conventional wisdom suggests is sure to be a gap between water demands and supplies. Significant money and energy are being spent both on lawyers preparing to fight over water and on expensive engineering schemes to augment the region’s supplies with ideas as extreme as a major new North American aqueduct to bring water from the Midwest.

The old water paradigm, and the tensions it creates, also makes environmental policies harder, because water users afraid of shortfalls are less likely to be willing to cooperate in reallocating supplies to environmental restoration. But contrary to the study’s projections and the conventional wisdom, in the three years since it was published, water use in the Colorado River Basin has declined. In fact, total Colorado River Basin water use peaked in the late 1990s, and has steadily declined since. 4,33


In 2014, the United States and Mexico conducted an unprecedented experiment that suggests the promise if we can embrace decoupling. In the midst of a deepening drought and dwindling reservoir supplies, the two nations released water from Morelos Dam, the last major dam on the Colorado River, into the desiccated Colorado River delta. A river channel that is usually dried was wet for a few months, triggering new growth of riparian habitat and equally important celebrations in Mexican communities like San Luis flanking the usually dry riverbed. The water was pushed down the channel in a pulse designed to mimic, on a tiny but ecologically important scale, the spring floods that once ran wide in the old river delta.

The international agreement that allowed the experiment was built in part on the promise of increased agricultural efficiency in Mexico, funded by environmental groups and governments on both sides of the border.34 It was the promise of decoupling, made real for the Mexican communities along the river’s path and the environment flanking the once dry river channel.

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