PD Editorial: Questions ahead on state water supply
A succession of December storms filled North Coast reservoirs to their highest level in months, but the most important gauge of California’s water storage is still stuck on drought.
This winter’s first assessment of the Sierra snowpack, conducted last week, found more snow on the ground than a year ago. But 2014 was a historically dry year, so that’s not much of a measuring stick. More important was determining the water content of the snow, which typically accounts for about a third of California’s water supply each year.
The conclusion: At 4 inches, it’s about a third of the average for this time of year.
That portends another dry year, and perhaps stricter water conservation measures, for much of the state.
“Although this year’s survey shows a deeper snowpack than last year, California needs much more rain and snow than we’ve experienced over the past two years to end the drought in 2015,” said Mark Cowin, the state Water Resources director.
How much more? The snow survey found 21.3 inches on the ground near Echo Summit near Lake Tahoe. A typical year would produce about 50 inches at that location, and state water officials say it would take about 75 inches to fill California’s reservoirs and recharge its aquifers after three years of drought.
The biggest impacts may be felt in the San Joaquin Valley, where growers have planted almost a million acres of lucrative but water-dependent crops, primarily almonds, in fields that once grew cotton and lettuce and could be left fallow when irrigation water - provided at highly subsidized prices - was scarce.
While major reservoirs on the North Coast are now filled to 75 percent of capacity and beyond, the reservoirs serving Central Valley water purveyors remain low. Lake Shasta is at 41 percent of capacity, the San Luis Reservoir at 39 percent, and the state Department of Water Resources estimates it will be able to deliver only 10 percent of the 4 million acre-feet requested from the State Water Project.
“Farms and some other areas will be hard hit if Water Year 2015 ends as the fourth full year of drought,” the department warned in a statement detailing its snowpack survey findings.
With Republicans controlling both houses, Congress is likely to renew efforts to waive environmental laws to deliver more water to Central Valley Project customers, but President Barack Obama is equally likely to veto any such legislation, and the federal courts have upheld regulatory decisions aimed at protecting salmon populations that sustain coastal communities in California, Oregon and Washington.
Scientists from the National Oceanic and Atmospheric Administration recently concluded that the drought resulted from natural conditions - specifically warm ocean water - not climate change. The next few months will be critical in determining whether the drought is over.
However, even if it is, California has a history of long dry spells, and higher temperatures associated with climate change could amplify the impacts of future droughts.
For city dwellers, that almost certainly means continual conservation efforts. For policymakers and Central Valley growers, it’s time to confront the reality that taxpayer-subsidized water and thirsty crops that can’t be fallowed are the wrong mix.