I came across this article today in Forbes, via Coyoyte Gulch. The topic is peak water.
In the article the author suggests that we have reached “peak water” as evidenced by the graph shown below:
I disagree with authors take. While withdrawals of water have been stable since the mid-1970s, I do not believe that this is a result of hitting peak water. One must remember that the first Earth Day and the environmental revolution in the United States occurred around this same time. As a result of the environmental epiphany of the 1970s people became more conscious about their water use, not necessarily because they were running out but because they became aware that their previous habits were simply wasteful. I still remember being inundated, as a child, by TV commercials and teachers to turn off the water while I brushed my teeth, but I have no recollections of being told that we were running out of water. In the 70′s the attitude about the environment changed, which changed our habits and our water use.
Further, in Colorado agriculture is responsible for 90% of water use. Prior to the advent and affordability of agricultural sprinkler systems and drip irrigation, most farmers employed flood irrigation. Flood irrigation is just as it sounds; flooding a field with water. As one can guess, this is not the most efficient or effectively method of irrigation. Consequently, improved irrigation methods plays an enormous role in the amount of freshwater withdrawn in the United States. While I haven’t performed the research to support this theory, I expect that much of the improved irrigation methods are related to improved crop yields and not a desire to maximize water use efficiency.
In sum, I think the leveling of our water use is not a reflection of hitting maximum withdrawals, rather it is simply a reflection of improved efficiency and awareness. When water use is grossly wasteful, small actions can dramatically improve efficiency. Obviously water shortages are typically a regional issue and effect different parts of the country differently. It may be true that areas of the arid west (Texas, Nevada, Colorado, Arizona) have hit peak water, but I believe the country as a whole still has a ways to go.