The true desert, wherein the production of crops is wholly dependent upon the artificial application of water, lies for the most part west of the Rocky Mountains. Its estimated area, 900,000 square miles, is probably slightly greater than that of the semi-arid region. An accurate determination of the relative size of each, however, is not possible until a comprehensive hydrographic survey has been completed. Contrary to popular opinion, this region is not a vast wilderness, desolate and unpromising. Between the mountain ranges lie many beautiful valleys, through which flow numerous streams fed by melting snows. Utah and Nevada contain large areas of sage-brush desert, comprising what is known as the Great Basin, which has no outlet to the sea, and is doomed to aridity by reason of the absence of living streams. Millions of acres of desert now inhabited by the coyote and the rattlesnake await only the coming of the engineer to wake to teeming fecundity.
In one important respect the arid and semi-arid regions are alike, and that is in the character of the streams. Almost without exception the rivers of the West are erratic and “flashy” in flow, are subject to long periods of drought and sudden and destructive floods. The full utilization of these streams for irrigation and power necessitates storage. In the control of floods, engineers have found their greatest problem, and one whose solution has taxed the skill, imagination and daring of twentieth-century genius.
WHEAT ON SHOSHONE PROJECT, WYOMING
This land was desert in 1908
National Irrigation
National irrigation became a fixed policy of the American Government with the passage of the Reclamation Act in June, 1902. The principal provisions of this act are briefly as follows:
First. A reclamation fund in the Treasury consisting of the proceeds from the sales of public lands in the sixteen arid and semi-arid states.[A]
[A] These include the states named in the first foot-note, with Texas added.
