WHY DO THESE PEOPLE need so much water? The answer, in large part, is corn. In the 19th century, cattle raised on the plains were shipped off to Chicago for slaughter, but over time meatpacking moved progressively closer to the cow. The stockyards grew so huge that their size became inefficient. Improvements in the railroads and, later, the advent of the semitruck made it cheap to transport meat without a central site of production. Decentralization also enabled management to escape Chicago’s strong labor movement. The industry is now dispersed across dozens of small plains cities: Dodge City and Garden City on the Arkansas in Kansas, and Liberal, which isn’t far, as well as Greeley, Colorado, and Grand Island, Nebraska, along the Platte. Each city and its small hinterland is a vertically integrated unit for producing beef, and corn is the cheapest means to fatten cattle before they are sent to the slaughterhouse. Consequently, many plains farmers now grow corn instead of dryland crops like wheat. But corn is water hungry and must have twenty inches of rainfall a year to survive and at least forty to thrive. Only one of the corn-growing counties along the upper Arkansas receives twenty inches of rain a year, and some places are so dry that they are, both technically and in outward appearance, deserts. Although corn is manifestly unsuited to the climate, it is grown in enormous volumes, and irrigation is what allows this to continue.
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