Irrigated Eden

The Making of an Agricultural Landscape in the American West

Mark Fiege

• Publisher: University of Washington Press
• Year: 2009
• ISBN:
  9780295989747
• Topic: Technology & Engineering
• Subtopic: Forestry
• Index: Technology & Engineering

Irrigation came to the arid West in a wave of optimism about the power of water to make the desert bloom. Mark Fiege's fascinating and innovative study of irrigation in southern Idaho's Snake River valley describes a complex interplay of human and natural systems. Using vast quantities of labor, irrigators built dams, excavated canals, laid out farms, and brought millions of acres into cultivation. But at each step, nature rebounded and compromised the intended agricultural order. The result was a new and richly textured landscape made of layer upon layer of technology and intractable natural forces—one that engineers and farmers did not control with the precision they had anticipated. Irrigated Eden vividly portrays how human actions inadvertently helped to create a strange and sometimes baffling ecology. Winner of the Idaho Library Association Book Award, 1999 Winner of the Charles A. Weyerhaeuser Award, Forest History Society, 1999-2000

1/ Genesis:
Water, Earth, and Irrigation Systems

Idaho's irrigated landscape developed during the nineteenth and early twentieth centuries from the interaction of agriculture with the Snake River valley environment. At the heart of this agriculture was a vision, shared by many people, of the human relationship to nature. Engineers, farmers, journalists, and social reformers frequently asserted that irrigation offered a method for transcending the limits that nature imposed. Most fundamentally, they said, it promised to liberate farmers from their dependence on precipitation. With irrigation, no tiller of the soil need fear drought. In 1900, Idaho state engineer D. W. Ross envisioned an environment in which the farmer could “laugh at the cloudless skies” because irrigation would allow him to have “the much needed moisture under perfect control.” The Twin Falls News, boosting local reclamation projects, concurred. “Irrigation is the science of farming,” the paper announced in 1904. “Rainfall farming is accidental farming.”¹

Irrigation advocates even claimed that farmers exercised a mastery not just over water but over nature in general. This was the message of the Idaho Republican in 1907 when it announced the arrival of R. H. Loomis, who had come to Idaho to settle on the Aberdeen-Springfield project near American Falls. “Loomis,” the paper stated, “left a nice home in Illinois to make a new home on this manless, homeless, weedless, bugless tract where he can put everything on the land just to his liking.” After journalist W. F. G. Thacher visited one of the Twin Falls irrigation projects in 1911, he similarly described farmers who worked the land with mechanistic precision. “Here,” wrote Thacher, “agriculture is reduced to one of the exact sciences. The farmer knows the elements of his soil; he knows the amount of water he has to depend upon; he knows practically what the weather will be. He proceeds like a chemist in his laboratory.”²

This rhetoric of a plastic and precisely controlled landscape appealed to farmers, especially those who had fallen victim to the hazards of “rainfall farming.” The writer Hamlin Garland recalled that the promise of irrigation instilled hope in his father, nearly broken after several disastrous years of wheat farming on the sunbaked and wind-blasted Dakota prairie. “The irrigated country is the next field for development,” Dick Garland told his son in 1893. “I'm going to sell out here and try irrigation in Montana. I want to get where I can regulate the water for my crops.” Hamlin and his brother eventually convinced their westering father that the family's destiny lay eastward, back in humid Wisconsin, but the elder Garland's words lingered in the son's memory: with irrigation, a man could regulate his water.³

In retrospect, the Garland brothers probably judged wisely when they decided to discourage their father from going farther west. Dick Garland would only have encountered environmental problems similar to the ones he hoped to escape. In places such as Montana or Idaho's Snake River valley, the proponents of irrigation never achieved the technical mastery that they promised. Behind their extravagant claims lay a complicated, difficult landscape in which farms did not function like laboratories and irrigators did not even attain their most basic objective: freedom from drought.

Contrary to the boosters' pronouncements, the irrigated landscape was not a place in which humans mastered nature. Rather, it was the site of an ongoing interaction between people and the land, a reciprocal interplay in which irrigators seldom if ever achieved the control they desired. Through plowing, planting, and irrigating, farmers and engineers tried to impose their designs on nature. They also adjusted to certain natural conditions, such as climate and landforms. By both manipulating the land and adjusting to natural conditions, they created a productive agricultural system. Their system, however, did not function with perfect precision. Streams and climate proved erratic, soil conditions changed, reservoirs and canals leaked. And if irrigation made crops and livestock possible, it inadvertently created a habitat for an array of vexatious flora and fauna: weeds, insects, mammals, birds. Con fronted with such problems, inhabitants of the irrigated landscape readjusted their agricultural systems and once again attempted to make nature bend to their will.

Gradually, this interaction between irrigators and nature created a new, complicated landscape in which human and natural systems overlapped, intermingled, and finally merged. Dynamic, ambiguous, often inscrutable, the irrigated landscape forced farmers to acknowledge that they could not always control nature as they wished. Behind their boasts they sometimes expressed frustration and doubt, and they grasped for new metaphors and images to explain their relationship to the complex environment in which they lived.

The irrigated landscape was the product, first of all, of the irrigators' encounter with the landforms and streams of the Snake River valley. This is a story of rock and soil, of changing climate and the transforming power of water, of fundamental physical processes that have shaped the world as we know it. And it is a story of people, the irrigators, interacting with these processes. Ancient forces laid down a substratum, the land; farmers and engineers then sought to incorporate this natural base into irrigation systems. From the 1860s through the 1920s, the irrigators built dams in canyons, excavated canals in the ground, and scraped fields from the soil. But in attempting to transform the Snake River valley into a tool of agricultural production, the irrigators exposed their systems to some of the very forces that had shaped the land in the first place. Thus the irrigators' efforts to change the environment resulted in unanticipated changes in their own irrigation works. From this convergence of hydraulic systems and geological forces, human and earth history, the irrigated landscape began to form.

Intense heat, pressure, and erosion, awesome powers that at once destroy and create, imparted the basic structure to the land that the irrigators would one day inhabit. Seventeen million years ago, during the Miocene, a giant meteorite smashed into the earth in what is now southeastern Oregon. The impact was so violent that it broke the earth's crust and opened a fissure in the underlying mantle. Enormous quantities of molten lava welled up and surged north into what would become Washington. But over millions of years, as the continental crust inched southwest across the opening, the “hot spot” shifted northeast, through the future Idaho. As the hot spot migrated it erupted with staggering force, producing a furrow that eventually became the Snake River plain. A thick layer of rhyolite, a pale volcanic rock, filled the furrow bottom. Later, after the hot spot moved on to the area that is now Yellowstone National Park, eruptions of a different sort added yet another layer of rock to Idaho's volcanic zone. Until 2,000 years ago, crustal stretching opened new fissures, and the earth spewed forth basalt that cooled and hardened into a black cap on the rhyolite. Volcanic ash, blown into the air, drifted on the surface, and there began to form soil.⁴

Volcanism defined the land that farmers later irrigated, but so did nearby mountains. During the Mesozoic, 70 to 80 million years ago, crustal movements shoved the Rocky Mountains into place. Later, the Oregon meteorite initiated a second phase of mountain building. Besides creating the migrating hot spot, the missile fractured the earth. As the continental crust slowly moved over the fracture, the Rockies shuddered and broke into huge blocks. This Bunyanesque stonework alternately thrust some blocks up and others down, creating a series of elongated ranges and basins that extended north-south. The Rockies and the “basin and range” would have covered all of southern Idaho, but the hot spot's eruptions left the furrow in their midst.

In the Pleistocene, water at last began to leave its mark on the land that irrigators would eventually transform: cool weather and increased moisture slowly turned the volcanic furrow into a fully developed river valley. Between 2 million and 3 million years ago, glacier-covered mountains sent streams gushing into the valley. Alluvial deposits formed at canyon mouths, and wind picked up the lightest sediments and laid them down across the Snake River plain. Water trickled into the ground and formed aquifers in gravel that lay sandwiched between separate lava flows. Eventually the water seeped into a major river, the Snake. Flowing along a westward gradient, the Snake and its tributaries slowly carved channels in the underlying volcanic rock. Then, about 15,000 years ago, a cataclysmic flood reshaped the Snake channel and gave the river its modern form. Lake Bonneville, which covered much of what is now northern Utah, absorbed so much inflow that its basin could no longer contain it. The water at last burst out, sending a vast rushing torrent into Idaho. The swirling waters scoured the Snake River canyon and created alcoves, rapids, and a series of magnificent falls.

Over the past 10,000 years, the cool, moist conditions dissipated, and the Snake River basin gradually grew warmer and drier. The glaciers retreated, and the Ice Age, the Pleistocene, came to an end. Surrounding mountain ranges blocked moist air and captured much of its precipitation, denying it to the valley. Rain and snow that did fall evaporated quickly into the crisp dry air. After several thousand years, aridity, the compelling reason for irrigation, became a predominant feature of the Snake River valley environment. To be sure, there were relatively brief periods when the climate grew cooler and wetter, but overall the valley became a dry place.

Yet within this dry environment, water remained an important agent of landscape change and formation. While profound geological forces laid down successive layers of rock and soil, an incessant exchange of moisture between earth and atmosphere—the hydrologic cycle—kept at least some water moving through the valley. As snow or rain, water fell to earth. There, plants absorbed and transpired it, and it evaporated into the air. Some water infiltrated the ground and percolated downward into gravel and the underlying volcanic rock, forming aquifers. Much water fell on mountains adjacent to the generally arid valley: the Boise, Sawtooth, Pioneer, Lost River, Lemhi, and Beaverhead ranges to the north; the Owyhee, Albion, Deep Creek, and other mountains to the south; the Caribou, Snake, and craggy Tetons to the east. Streams poured from these mountains and converged on the Snake, which flowed from the eastern ranges and followed its westward course in a huge arc across southern Idaho. The pattern never ended; the hydrologic cycle repeated itself, on and on, in perpetuity.⁵

Earth history had produced the Snake River valley and driven the hydrologic cycle; this land and the ancient natural processes that shaped it would soon attract thousands of irrigation farmers. These people first came to the lower valley in the 1860s, and they settled adjacent to the Bruneau, Boise, Payette, Owyhee, and Weiser rivers, tributaries of the Snake. Here they diverted water to their fields and raised crops for sale in nearby mining camps. Their presence helped boost Idaho's territorial population to nearly 15,000 people in 1870.⁶

The influx of farmers intensified in the late 1870s and early 1880s, when the Oregon Short Line and the Utah and Northern, subsidiaries of the Union Pacific Railroad, penetrated the valley. Idaho's doors opened to the wider world; outside markets beckoned, and the Snake River valley's fertile soils, ample sunshine, and water—all extensively advertised by the railroads—lured fresh settlers to the area. Some newcomers moved into the lower valley, but many others established farms and irrigation systems in the upper valley above American Falls. The population rose accordingly: by 1890, the year Idaho achieved statehood, the total stood at roughly 88,000; by 1900, some 161,000 people made their homes here.

The stream of migrants peaked during the first two decades of the twentieth century, as thousands of people claimed farms under the 1894 Carey Act and the 1902 National Reclamation Act. Most of them settled along the central Snake, midway between the upper and lower valleys. Largely because of this intensive round of irrigation development, Idaho's population more than doubled between 1900 and 1910, rising to about 325,000. The rate slowed in the following decade, but growth continued. By 1920, some 431,000 people inhabited the state.

Although they shared an interest in irrigation, social and cultural diversity characterized the people who sought to fashion the Snake River valley into an agricultural landscape. Real estate salesmen, implement dealers, bankers, lawyers, railroad managers, investors, journalists, and public officials—these individuals promoted, financed, and administered irrigation systems and farms. Engineers designed dams and canals, and construction companies and their workers built them. Most important were the people who actually settled and farmed the land. Quakers, Mormons, and Mennonites became irrigators, as did Japanese, Germans from Russia, and Indians on the Fort Hall Reservation. Farmers from the Midwest, the Great Plains, the South, and even other irrigated areas in the West settled in the region. Probably the greatest single migration to the Snake River valley came from Utah and the Church of Jesus Christ of Latter-day Saints. The Mormons established their first agricultural settlement in the upper valley in 1879; by 1914 about 36,000 church members, including recent arrivals from Europe, made their homes here.⁷

No single factor drew these folk to the irrigated landscape, but in almost every case the environment had something to do with their relocation. The belief that they would find cheaper land and a more dependable water supply attracted some; the prospects for land speculation lured others. A few came in the hope that the Snake River valley's dry, sunny climate would restore lost health. A substantial number recognized that irrigation offered one of the last opportunities in industrializing America to acquire a farm. To those who would leave urban homes and industrial jobs and migrate to places like the Snake River valley, the agrarian dream still seemed possible. By turning land and water into an agricultural landscape, this new generation of pioneers sought to recapture a vanishing way of life.⁸

Idaho irrigators of whatever sort faced a difficult task. They would have to dam streams and divert them into extensive networks of canals and ditches, and they would have to strip the land of sagebrush, then painstakingly smooth, grade, and plant it. They would have to grow crops and raise livestock in an environment that had been, but a short time before, a desert. Yet, on the whole, they had great confidence in their power to manipulate earth, water, plants, and animals as they wished. Thus their guiding vision, so well expressed by D. W. Ross, the Twin Falls News, the Idaho Republican, and W. F. G. Thacher: through irrigation they would make a landscape in which human ingenuity prevailed over the vagaries of nature.

To achieve their objectives, farmers and engineers sought to intercept the unceasing physical process that kept water moving through the Snake River valley: the hydrologic cycle. The irrigators had to shift the cycle out of its regular course and make it serve agricultural purposes. Farmers and engineers often referred to this work as “conquest”; they had to defeat nature, “tame” the Snake, and make it do their bidding. Yet conquest was not the only way that they described their manipulation of the hydrologic cycle. They also believed that they were working with nature. To move water, irrigators had to site dams and canals in accordance both with existing landforms and watercourses and with a powerful, elemental force: gravity. Partly this siting was mere expedience, a practical, efficient, commonsense use of nature. But by merging their systems with the land and the hydrologic cycle, the farmers and engineers believed that they were developing and perfecting the earth's raw potential. Indeed, the earth itself at times seemed like God's unfinished construction site; its topographical features already carried the outlines of a future landscape that the irrigators would complete. As a manifestation of providential design, the earth seemed to invite the dams and canals that the irrigators would build.⁹

Along the Snake and its tributaries, the irrigators found “natural” sites for erecting dams. Early farmers tended to settle on bottomland, places at which they could most easily and efficiently turn water out of streams and into ditches that carried water to the fields. During the 1880s, Mormon pioneers converged on the Snake River forks country, around where the Teton, Henrys Fork, and Snake (South Fork) flowed together. Topographic maps from 1876 and 1879 labeled portions of this low-lying area “beaver swamp.” The Mormons congregated in the forks country for much the same reason as the beaver: it was easy to build dams there. Meander bends or low-lying banks allowed them to divert water with relatively minimal effort. Each year the farmers built small rubble, brush, and canvas dams that channeled water into their ditches. Some farmers used natural river riffles to help guide the water. Construction of small dams was usually a seasonal routine. High water in spring wiped out the structures, making new construction necessary before irrigation could begin.¹⁰

Large irrigation projects, sponsored by corporations and government agencies, faced greater technical and environmental challenges in building dams than did the small irrigators. But like the folk builders, professional engineers situated their large earth and concrete structures in places that seemed natural for catching and diverting water. Canyons, valleys, and lakes provided efficient and thus relatively inexpensive places for dam construction. Paul Bickel and his staff, engineers of irrigation works around the town of Twin Falls, designed dams and reservoirs that incorporated natural topography. On the south central Snake, the engineers incorporated two volcanic rock islands into Milner Dam, a rock-fill and concrete structure. The Twin Falls News noted that the earthen dam that formed Dry Creek Reservoir, which fed water into the Main Canal on the south side of the Snake, appeared to be well suited to the surrounding land. “It would seem,” remarked the paper, “that bountiful nature had provided the reservoir in the most convenient loca...