SENTINEL WATCH August 2, 2004 Issue

Water in the West

By Channing Walker

Not everyone in California's Yosemite National Park these days is gazing up at the breathtaking granite walls of El Capitan and Half Dome, which rim the valley and captivate rock climbers with the awesome challenge they present. A handful of people are instead gazing down at reams of data detailing the snowmelt of this past spring and earlier springs.

This past season there was plenty of snowfall. But, as part of an ongoing trend, the snowmelt began sooner. As average temperatures have risen over the last 50 years—and many experts feel that's global warming at work—the snowmelt has started earlier and earlier. Why is this a problem? Mountain snowpacks, essentially, function as storage towers for the West. The water they hold in the form of snow through much of the spring and early summer gradually releases through the hot, dry months. This earlier snowmelt isn't just happening in the Sierras, but also in the cascade and Rocky Mountains. Taken together, those three ranges supply most of the West's water. One researcher tracking this phenomenon recently summed it up: "The mountain ranges are essentially draining and drying earlier."

The encouraging news is that a problemsolving spirit is catching on. Water agencies are seeking out more ways of storage. Farmers are implementing more efficient delivery systems. And businesses and even homeowners keep buying better and better options for everything from less wasteful dishwashers to low–flow showerheads.