Wet or Dry Winter Aside, Changes Ahead for Sierra Snowpack

Snowmelt from the Sierra provides more than a third of California’s drinking and irrigation water. It is the lifeblood of the water system that supplies 25 million Californians and millions of acres of productive farmland.

But for all its importance, the mountain snowpack is particularly sensitive to climate variability. Warmer temperatures could reduce the snowpack by up to 40% over the coming decades, eliminating a key source of “natural” water storage and raising new uncertainties for our water supply system. Snowpack runoff flows into the American River, which is an important water supply source for SSWD.

State water managers say the effects of climate change already are being seen, with the driest conditions in 20 years recorded in the 2006-07 water year. Many local water agencies are preparing contingency plans to deal with these new uncertainties.