Friday, April 27, 2012

Historic drought highlights importance of statewide water planning

Hannah Holm in the Grand Junction Free Press (Colorado): In the Grand Valley, we rely on flows in the Colorado and Gunnison rivers to sustain our orchards and alfalfa fields, and the Grand Mesa for most of our drinking water. These sources also keep our lawns and shade trees lush, making life in our desert valley quite a bit more comfortable than they would be otherwise as temperatures rise in the summer — or, this year, in mid-spring!
Generally speaking, when we turn on the tap, water appears, and we use it as we like. The last time the Grand Valley residents faced water restrictions was in 1977. However, a historically low snowpack combined with an earlier-than-normal runoff promises to make the summer of 2012 a challenging year for water management in arid Mesa County.
As of April 24, the Colorado River Basin snowpack in Colorado held just 38% of the water content it would have on this date in an average year; the Gunnison River Basin held 34% of its average water content for this date. In 2002, the last extremely dry year, the Colorado River snowpack was doing about the same at this point; the Gunnison was a bit worse at 25%.
We're lucky that this historically dry water year is following a historically wet one last year, which provided exciting high river flows, filled local reservoirs, and raised levels in Lake Powell, the “bank account” used by Colorado, Utah, Wyoming and New Mexico to help meet obligations to our downstream neighbors in Arizona, California, Nevada and Mexico.
As for next year, who knows? Variability from year to year is the norm, and predictions from one year to the next are notoriously unreliable. There are reasons to believe we could face more challenging times ahead.
...Meanwhile, water consumption doesn't seem to be going anywhere but up.
Blue Mesa Reservoir in Colorado, shot by Nationalparks, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 2.5 Generic license

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