The Fate of the Southwest

My Master's Thesis is entitled: Water Conservation: Guidelines for Mitigating the Impacts of Climate Change on Water Availability for Maricopa County, Arizona. And of course, I did an in-depth investigation of the Colorado River since it is this river that allows populous cities and expansive agricultural fields to flourish in the desert that is the American Southwest.

The Colorado River is infamous for being the most completely allocated river in the world as well as being the most legislated, regulated, managed, and politicized. Its waters have been meticulously divided and are rationed among the states that share its watershed (CO, WY, UT, NM, AZ, NV, and CA). Unfortunately, when the river was divvied up in the early 1900s, a small data set of streamflow measurements was taken during one of the hydrologically wettest periods in the the river basin’s history. Bottom line is there is much less water available than was apportioned--the river is overallocated. So much so that the mouth of the river has historically emptied into the Gulf of California, but today the river never (rarely if ever) flows to its end, leaving the delta dry.

The Colorado River has an elaborate reservoir system--the largest in the US--and is undoubtedly the most important component of life in the Southwest as it is today. Lakes Powell and Mead have the capacity to store four years worth of water and produce hydroelectric power for most of the Southwest. But there has been a drought in the Colorado River Basin for the past decade, and severe and sustained droughts are not uncommon in the Basin. Tree-ring samples indicate that many droughts have occurred since A.D. 762. The current drought has been a wake-up call to water managers that has identified the fragility of the reservoir system to climate variability. Lake Mead is at its lowest level since it began filling in 1936 threatening hydroelectric generation as well as water rations to Arizona and Nevada. The first-ever shortage guidelines may be enacted if the lake level declines another eight feet.

What will happen if this drought continues? Will there be enough water? Will coal-fired power plants replace hydroelectric generation? I don't know, but what I know for sure is that life in the Southwest will need to change. There will need to be an emphasis on water sustainability, including water conservation and water-use efficiency. If not, the over 25 million people that live in the Southwest will have to find a new home.