The several feet of snow expected in the Sierra this week is expected to considerably change the look of California's drought map.
At this time last year, 45 percent of the state was in an exceptional drought, which is the worst possible rating. Officials said only 18 percent of California currently remains dry.
"Our biggest reservoir is all the snow that falls during the winter because when it melts it can fill all the big reservoirs throughout the state," said Marty Grimes, spokesperson for the Santa Clara Valley Water District.
Half of the water used in Santa Clara County, among others, comes from outside sources and is incredibly dependent on the Sierra snow pack.
Lexington Reservoir was just one water source that was greatly impacted by last year's reduced snow pack, when water levels sank to new lows.
On Monday, reservoir runners were giddy in the rain.
"I think it's fantastic," Campbell-resident Lydia Van Muckey said of the wet weather. "Makes me really sad when I'm going on drives and see the reservoir low, so this is good."
And while this week's moisture will make a dent in the drought, experts warn conservation continues.
"We should always save," Grimes said. "We should never go back to a day when wasting water is acceptable."