WATER WARS CONTINUED

Pushing the Colorado to its limit

By Matt Ford | Published: February 13, 2008 - 09:35AM CT

Lake Mead is the largest man-made lake in the United States; it consists of the water from the Colorado River held behind the Hoover Dam. Through a series of aqueducts, it supplies water to much of the southwestern United States. However, if current and projected water usage patterns and predicted climate change scenarios occur, then, according to a pair of researchers from the Scripps Institute of Oceanography, Lake Mead may dry up.

Without Lakes Mead and Powell, the researchers say that the Colorado river system will not have enough of a buffer to withstand a dry year or a sustained drought. Marine physicist Tim Barnett and climate scientist David Pierce computed that the Colorado river system is experiencing a net water loss of almost one million acre-feet of water per year. The amount of water being lost in a single year would be enough to supply eight million individuals.

The scientists' analysis was based on Federal Bureau of Reclamation records of past water demand and calculations of scheduled water allocations and climate conditions. Their results showed that, even if steps are taken towards implementing mitigation procedures, then the system could still run dry. Their paper is scheduled to be published in an upcoming edition of the AGU journal Water Resources Research. The effect of climate change in their work was factored in through a decrease in runoff entering the river using numbers reported in other peer reviewed journals. The other articles forecasted a consistent reduction between 10 and 30 percent over the next 30 to 50 years­that's enough water to affect between 12 and 36 million people.

The end result is that there is as much as a 10 percent chance that Lake Mead will be dry by 2014, and a 50 percent chance it will be dry by 2021. In addition, they calculated that there is a 50 percent chance the water level will be too low to use to generate hydroelectric power by 2017.

The duo state that they used conservative estimates of the situations relevant to their calculations, which means that reality could be worse then their predictions. They end their paper with the following: "Today, we are at or beyond the sustainable limit of the Colorado system. The alternative to reasoned solutions to this coming water crisis is a major societal and economic disruption in the desert southwest; something that will affect each of us living in the region."

Water Resources Research, 2008. To be published