Cadillac Desert_ The American West and Its Disappearing Water - Marc Reisner [3]
If you begin at the Pacific rim and move inland, you will find large cities, many towns, and prosperous-looking farms until you cross the Sierra Nevada and the Cascades, which block the seasonal weather fronts moving in from the Pacific and wring out their moisture in snows and drenching rains. On the east side of the Sierra-Cascade crest, moisture drops immediately—from as much as 150 inches of precipitation on the western slope to as little as four inches on the eastern—and it doesn’t increase much, except at higher elevations, until you have crossed the hundredth meridian, which bisects the Dakotas and Nebraska and Kansas down to Abilene, Texas, and divides the country into its two most significant halves—the one receiving at least twenty inches of precipitation a year, the other generally receiving less. Any place with less than twenty inches of rainfall is hostile terrain to a farmer depending solely on the sky, and a place that receives seven inches or less—as Phoenix, El Paso, and Reno do—is arguably no place to inhabit at all. Everything depends on the manipulation of water—on capturing it behind dams, storing it, and rerouting it in concrete rivers over distances of hundreds of miles. Were it not for a century and a half of messianic effort toward that end, the West as we know it would not exist.
The word “messianic” is not used casually. Confronted by the desert, the first thing Americans want to do is change it. People say that they “love” the desert, but few of them love it enough to live there. I mean in the real desert, not in a make-believe city like Phoenix with exotic palms and golf-course lawns and a five-hundred-foot fountain and an artificial surf. Most people “love” the desert by driving through it in air-conditioned cars, “experiencing” its grandeur. That may be some kind of experience, but it is living in a fool’s paradise. To really experience the desert you have to march right into its white bowl of sky and shape-contorting heat with your mind on your canteen as if it were your last gallon of gas and you were being chased by a carload of escaped murderers. You have to imagine what it would be like to drink blood from a lizard or, in the grip of dementia, claw bare-handed through sand and rock for the vestigial moisture beneath a dry wash.
Trees, because of their moisture requirements, are our physiological counterparts in the kingdom of plants. Throughout most of the West they begin to appear high up on mountainsides, usually at five or six thousand feet, or else they huddle like cows along occasional streambeds. Higher up the rain falls, but the soil is miserable, the weather is extreme, and human efforts are under siege. Lower down, in the valleys and on the plains, the weather, the soil, and the terrain are more welcoming, but it is almost invariably too dry. A drought lasting three weeks can terrorize an eastern farmer; a drought of five months is, to a California farmer, a normal state of affairs. (The lettuce farmers of the Imperial Valley don’t even like rain; it is so hot in the summer it wilts the leaves.) The Napa Valley of California receives as much Godwater—a term for rain in the arid West—as Illinois, but almost all of it falls from November to March; a weather front between May and September rates as much press attention as a meteor shower. In Nevada you see rainclouds, formed by orographic updrafts over the mountains, almost every day. But rainclouds in the desert seldom mean rain, because the heat reflected off the earth and the ravenous dryness can vaporize a shower in midair, leaving the blackest-looking