Arizona’s Water Strategies

Richard Horton

Arizona has experienced two severe and sustained droughts in the first half of the 20th century, one in the 1900s and one in the 1950s. Arizona is now experiencing a third modern drought that began in the mid-1990s.

Arizona has a limited supply of water from current sources. According to the latest information from the Arizona Department of Water Resources, 41% of Arizona’s water comes from groundwater, 36% from the Colorado River, 18% from in-state lakes and rivers, and 5% from reclaimed water.

The Colorado River is Arizona’s most significant renewable water supply, with a yearly allocation of 2.8 million acre-feet. Approximately 1.5 million acre-feet go to the Central Arizona Project for distribution to Maricopa, Pinal, and Pima counties. With 336 miles of canals, water flows throughout the project for city and agriculture use. The remaining allocation goes to Mohave, La Paz, and Yuma counties. Unfortunately, over the past 20 years, the available water has substantially diminished with the extensive drought conditions. As a result, Lake Mead’s water level has fallen more than 200 feet, in danger of reaching critically low levels. Continuing lower levels could impede the ability to generate electricity for the Southwest.

Current entities are developing programs to provide maximum water use, but we must find other opportunities to ensure a long-term water supply. Let’s think “out of the box.”

One idea or solution to the long-term water supply would be to bring water from the Yellowstone River and divert it into the Green River. The Green River starts in west-central Wyoming and generally flows south towards eastern Utah, where it continues south and joins the Colorado River south of Moab, Utah. Then, it starts its journey toward the states that depend on Colorado River water. With the water diverted from its original point, the Mississippi River, it could also help with flooding in those states that border the Mississippi.

The Green River, I believe, would be a reasonable economic fix for some of the water shortages since it already delivers water to the Colorado River. Also, concerning entities would have already litigated the legal challenges.

The second water source could be from the Columbia River, with the design joining the Green River at some point. The Columbia River Basin covers 258,000 square miles and includes parts of seven states and one Canadian province. In its 1,200-mile course to the ocean, the river flows through four mountain ranges and drains more water into the Pacific Ocean than any other river in North or South America.

One acre-foot of water equals 326,000 gallons of water, enough to provide three medium-sized homes for one year. In the next 20 years, the population could double in the Southwest.

A stable, secure, long-term water supply is the foundation Arizona’s diverse and growing economy needs to prosper.