There’s a U.S. Bureau of Reclamation graph making the rounds that captures the core issue going forward on the Colorado River Basin.
I first noticed it in Jennifer Pitt’s congressional testimony in early April. At the “Implications of Lower Lake Levels” symposium I just attended in Las Vegas, it showed up in three different talks (Terry Fulp, Brad Udall and Paul Miller – all links to PDFs of their slides).
It also features prominently in the proposal submitted last year by the Colorado River Basin states (another big PDF) that evolved into the Colorado River Basin Water Supply and Demand Study now underway. Here’s how that proposal described the problem in a nutshell:
The Basin States include some of the fastest growing urban and industrial areas in the United States. Nevada, Arizona, and Utah are each ranked among the five fastest growing states in the country. The continued growth and sustainability of the communities and economies of metropolitan areas such as Albuquerque, Denver, Las Vegas, Los Angeles, Phoenix, Salt Lake City and San Diego is tied to future water availability from the Colorado River. Based on a compilation of population projections from various water districts throughout the Basin States, the population dependent on the Colorado River and its tributaries could grow by 25 million over the next 40 years, leading to an increase in water demand of as much as 5 maf annually. Demand for water for other uses including the environment, recreation, and Native American water rights settlements also continues to increase. Potential future increases in temperatures in the Basin, as have been observed in most of the Basin over the past 30 to 40 years, would increase evaporation-transpiration from vegetation, leading to further increases in water use and water lost from evaporation from reservoirs.
There are a lot of embedded assumptions lurking behind The Graph that I haven’t yet worked through. But I like to think of its simplicity in Darwinian terms. Its rapid reproduction and dispersal in the wild suggests it is telling a story that serves a lot of our needs.