February 27, 2017

Upcoming Survey Will Show Above-Average Snowpack in California

But Climate Change Creates Uncertainty about Future Water Supply, U.S. Science Group Says

OAKLAND, Calif.  (February 27, 2017)—The California Department of Water Resources will conduct its snow survey on March 1. Already, electronic sensors show that the snowpack and its water content throughout the Sierra Nevada are well above average.

While that is good news after nearly five years of drought, the bigger question is what will happen to that snowpack. Abundant amounts of snow now do not necessarily mean plenty of water later this year or next since California has received more rain than its reservoirs can store and warm weather could melt much of the snow that has accumulated in the Sierras.

“Instead of making its way into our faucets, the snow we have now could be washed away into the ocean,” said Juliet Christian-Smith, senior climate scientist and water expert at the Union of Concerned Scientists. “Even in heavy snow years like this one, global warming is the wild card in our water security.”

Scientists have long warned that climate change causes more extreme weather – both droughts and floods. Higher temperatures pose a risk that the snow will not stick around through the spring and early summer to melt into reservoirs when water demands are the highest in the hotter months.

“With 2016 being the warmest year on record for the third year in a row, that spells trouble for snow,” said Christian-Smith, noting that the Sierra snowpack accounts for one-third of California’s water supply. “Recent heavy rains and flooding are consistent with a warming planet, and such events are expected to become more common over time.”

This year’s wet winter also has provided stark evidence that our aging water infrastructure isn't built to handle either record precipitation or early snowmelt. California underground aquifers – badly depleted during the drought -- have about three times the storage capacity as all of the state’s above-ground reservoirs.

“California’s new climate reality requires that we transform our water system and plan for a very different future,” said UCS Western States Director Adrienne Alvord. “Groundwater is key to adapting to climate change in California since heavy rains can be captured underground and stored for use during prolonged periods of drought.”

The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet's most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe, and sustainable future.