The Disappearing Colorado River: Historic and Modern Attempts to Manage the Lifeline of the United States Southwest

Abstract

Historic Native American and modern civilizations have been forcing the unstable use of the Colorado River and adjacent land resources for centuries. Much can be learned from past Native American cultures that created irrigation systems to offset low rainfall. These lessons learned can be applied to our modern civilization. We can learn a lot from their previous behavior and experiences and could apply the lessons learned to our current disappearing Colorado River situation. Little of the Colorado River water flow reaches the international border with Mexico near Yuma, Arizona. Intensive consump-tion, mostly in the United States, has dried up the lower 160 km of the river. Since the 1960s, the Colorado River has rarely flowed into the Gulf of California and when it does it becomes is a major international news event. The Colorado River Delta is drought prone and its headwater tributaries are a vital source of water for 40 million people. The Colorado River has whitewater rapids, canyons, and many United States National Parks. The tributary and river flow is managed by an extensive system of dams, aqueducts, and reservoirs. Most years the entire Colorado River flow is used for United States agricultural irrigation and domestic water supply purposes. The agricultural and urban needs in the United States are continuing to grow and it appears the days of Colorado River flowing into Mexico and the Gulf of California are numbered and declining every decade. The Colorado River is disappearing and restoration efforts appear to be too little too late. If the Colorado River valley is ever going to recover management lessons and failures learned from the Native Americans, including the Hohokam,