Snow and rain in the Sierras during the winter rainy season are crucial for California water. This year though, March snow readings (PDF) were less than in January and February, the opposite of what normally happens. Barring unexpected deluges of rain, the California drought will continue through 2015, as the rainy season ends on April 1.
California reservoirs statewide now average 67% full, with a scattered few are full while others are at single digits of capacity. This means more wells will be drilled, with more aquifers put under stress. At some point, mandatory rationing may be necessary.
Statewide, 103 electronic sensors found today’s snow water equivalent to be 5 inches, 19 percent of the March 3 multi-decade average. When DWR conducted the season’s first two manual surveys on December 30 and January 29, the statewide water content was 50 percent and 25 percent respectively of the historical averages for those dates.
In normal years, the snowpack supplies about 30 percent of California’s water needs as it melts in the spring and early summer. The greater the snowpack water content, the greater the likelihood California’s reservoirs will receive ample runoff as the snowpack melts to meet the state’s water demand in the summer and fall.