California has had one weird winter this year: lots of snow and rain early, and almost none since January. It’s in years like this that it’s especially crucial to know just how much water to expect from melting Sierra snows — runoff that provides about a third of the state’s water supply. Current estimates combine patchy measurements with a kind of sophisticated guesswork. But that may be about to change with new technology that’s currently being tested.
There are more than 130 hydropower projects in California. They take advantage of steep terrain and gushing mountain rivers to churn out about fourteen percent of California’s electricity. It’s a delicate balance, dependent on heavy snow in the winter, and heavy runoff in the spring as the snow melts. But climate change threatens to throw that balance out of whack, a problem that federal regulators have chosen to ignore.
Today, state water officials will trek into the Sierra for one last snow survey of the season. All of the late-season storms — there was snow falling in Tahoe as recently as this week–would seem to portend a shot in the arm for California’s water supply. But there is still much we don’t understand about how and when the mountain runoff offers up its annual gift of water for reservoirs and irrigation.
This aired on The California Report on 4/31/10 and was accompanied by a blog post on the Climate Watch blog.