The Arid West—Where Water Is Scarce - Desert Boom

Cities and towns in Arizona, Nevada, Utah, and New Mexico have experienced unprecedented growth in the recent past. The creation of new jobs and the influx of more people continue. The growth of the job market there since 1980 has exceeded that of the United States as a whole, and population increase has mirrored the job opportunities. Some new residents, drawn by the natural beauty of the West, "telecommute" to offices in faraway cities.

According to data from the U.S. Census Bureau, population growth exploded in the West between 1990 and 2000. (See Figure 8.2.) Nevada, where the population increased by 66.3% during those years, and Arizona, with an increase in population of 40%, lead the nation.

The Census Bureau projected continued significant population growth in the West through the year 2025. In its report Population Projections for States by Age, Sex, Race, and Hispanic Origin: 1995 to 2025, the Bureau projected that population in the West would increase at a rate of nearly twice the national average from 1995 through 2025. California, which contained 12% of the U.S. population in 1995, was projected to contain 15% of the population by the year 2025, adding about 17.7 million people during the thirty-year period.

In its November 23, 1998, seminar (updated May 22, 2003), the United States Global Change Research Program (USGCRP) discussed how population increases have affected use of water from the Colorado River Basin. According to the seminar, four of the top five fastest-growing states in the country are in the Colorado River Basin. In addition, populations in the northern Mexican states of Sonora and Baja are also increasing significantly at 5% per year, a rate of growth expected to continue.

The accompanying increase in water demand has been very rapid. In 1988 Nevada used less than 130,000 acre-feet of its 300,000 acre-foot Colorado River entitlement. By 1995, however, its use of the water grew to 225,000 acre-feet per year. The state is expected to use its full entitlement before 2025. Moreover, the population of Las Vegas grew by more than 26% between 1990 and 1994, and the total population of southern Nevada in 1990 (800,000) is expected to more than double by the year 2020. Populations in Arizona and in the northwestern region of Mexico are both expected to grow by 90% over the same period.

Growth has another price. Water is the ultimate source of growth and political power in the arid West. Often, water has to be brought to western cities from distant sources. Although most of the West's cities sprang up alongside rivers, their increasing needs for water long ago outstripped the local supplies. Nationwide, southwestern states are more dependent on public and private community water systems than are other states where use of individual wells is more prevalent.

Drilling a well in the desert is unlikely to produce an adequate supply of water. Hence, even the smallest communities now depend increasingly on water imported from other states. In 1990, for the first time, states in the lower Colorado River Basin (Arizona, California, and Nevada) used their full 7.5-million acre-foot allotment. The unprecedented growth of Phoenix, Arizona, and Las Vegas, Nevada, has resulted in warnings to California from those states that they will likely cut their annual allotments of water to California, perhaps by as much as 50%.

FIGURE 8.2
Percent change in resident population for the fifty states and the District of Columbia, 1990–2000
SOURCE: Adapted from "Figure 1. Percent Change in Resident Population for the 50 States, the District of Columbia, and Puerto Rico: 1990–2000," in United States Census 2000 Resident Population, U.S. Census Bureau, December 2000, http://www.census.gov/population/cen2000/map01bw.pdf (accessed April 13, 2005)

Changes Coming to California

Southern California relies on the Colorado River for 70% of its water. For years, California has been able to take more than its lawful portion of Colorado River water because the other six states dependent on the river—Arizona, Nevada, Colorado, Utah, Wyoming, and New Mexico—did not need their allotted share. However, that situation is changing as the population of the West surges, and the other states are pushing the government to curtail California's use of water. California is currently exceeding its allotment by at least one-fifth.