Colorado River water: Hoover Dam
In the arid West, politicians long had their eyes on the Colorado River as a source of water for their states. In 1922, California, Arizona, and Nevada (the lower basin states), together with Colorado, Utah, Wyoming, and New Mexico (the upper basin states), negotiated the Colorado River Compact at the direction of Secretary of Commerce Herbert Hoover. This agreement allocated the estimated flow of 17.5 million acre-feet per year. Some 7.5 million acre-feet were allocated to each basin, with a bonus of 1 million acre-feet given to the lower basin and 1.5 million acre-feet reserved to Mexico. Two problems remained: calculating the flow estimate and determining how to draw on the Colorado’s water.
Rainfall had been plentiful in the Rockies during the early twentieth century, so the estimate of 17.5 million acre-feet seemed accurate. It was not. The rainfall during the early twentieth century was abnormally high, and the Colorado River has rarely produced 17.5 million acre-feet in flow since the compact was signed. Since the 1930’s, the flow has averaged 11.3 million acre-feet per year. That problem would crop up in the future—the more immediate issue after the compact was agreed to was how to tap the river’s water.
In 1930, Congress authorized Boulder Dam (renamed Hoover Dam), and construction began in 1931. It was jointly carried out by eight engineering firms, some of which (such as the Bechtel Corporation) would become massive construction firms in the future. Construction of Boulder Dam provided a stimulus to the Western economy, as large numbers of men worked on the project. The dam became a model for later projects throughout the world. It was completed and the first electric power generated in fall of 1936. Hoover Dam generated such a large amount of electric power that it paid for itself. Lake Mead extended upstream for a hundred miles, providing the water that could be used to irrigate and provide drinking water for California and the Southwest.
The population of California was growing during the 1930’s, and the Colorado River was seen as a short-term solution to its water needs. Initially, much of California’s water allocation went to agriculture, with nearly 3 million acre-feet irrigating the truck farms of the Imperial Valley. By the 1950’s, California was already using its 4.4 million acre-foot allotment under the Colorado River Compact and was searching for additional sources of water both within its borders and elsewhere. It soon began to pump 700,000 additional acre-feet from the river. Initially, this was not a problem, but as the population of the intermountain states began to grow, they too wanted to ensure their allocations from the river. The small gambling town of Las Vegas, Nevada, started to grow during the 1950’s, creating a significant new demand for electric power and water in the desert. Not only did the citizens of Las Vegas need a large amount of water for drinking and irrigation of their lawns, but the hotels of the city often had large decorative fountains and lakes. The Mirage Hotel, for example, uses more than 1 million gallons of water a day. Abundant water was part of the ambience of the Las Vegas hotels, an ambience that was enormously profitable to the city.