Snowpack nearly nonexistent

 

With parts of eight western states experiencing drought conditions for the fourth consecutive year, the March snow totals for one-third of the recording stations in the Sierra Nevada and the Cascade mountains are some of the lowest ever recorded. In California, the Sierra Nevada is 18 percent of the April 1 average. 

For the first time since the snow surveys began in 1939 to forecast runoff, some locales are completely snow-free.

In nearly all drainages, downstream users are bracing for reduced summer stream flows. And even though parts of the Cascades in Oregon and Washington have experienced normal precipitation, much like in the nearby national parks, snow remains only on north-facing slopes at elevations above 9,600 feet.

The Mineral King area of Sequoia National Park is a prime example. Snow in the Mineral King valley is nonexistent; in Farewell Gap, near the remote sensor (9,600 feet), there is a fairly consistent one to two feet of snowpack.

In past seasons, as recent as 2011 and prior to the current run of drought years, in March there was snow in the Mineral King valley and five to six feet at 9,600 feet in Farewell Gap. The content of that pack was 30-40 inches of water just waiting to become runoff with warmer temperatures in May and June.

In a drought, vegetation along the drainage soaks up most of what will melt for runoff in the current season. Climate change scientists have predicted since the 1990s that this situation will become the new normal for the central and southern Sierra Nevada regions. A part of that forecast also includes later season rainfall events and less snow.

What this means for water users is that conservation will no longer be voluntary as more jurisdictions legislate to restrict use and make mandatory water regulations. On Thursday, March 19, Governor Jerry Brown announced emergency drought legislation, further strengthening water conservation in the state.

Since February 2014, the State of California has pledged more than $870 million to support drought relief, including money to feed workers who experienced drought-related losses, dollars to secure emergency drinking water, and bond funds for projects to help local communities save water and build new drought-resilient systems.         

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