The storms pummeling the state this year also contradict forecasts of a new climate normal of persistent drought. California is on track for its wettest winter on record....This sudden turn of climate events is consistent with California’s cyclical weather patterns.
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Yet the state lacks sufficient infrastructure to store the excess precipitation. California’s largest reservoirs are nearing capacity, which has required regulators to release billions of gallons of water to prevent flooding. More than 4.4 million acre-feet of water—enough to irrigate about 1.5 million acres of land or sustain four million households annually—have been discharged from Shasta and Folsom Lakes this year.
Some of the releases can be stored or used downstream, but millions of acre-feet of water will invariably flow out to the San Francisco Bay. The pumps at the Sacramento-San Joaquin River Delta are limited by mechanical capacity and species protections. During the spring, melting snowpack in the Sierras—which supply more than half of California’s annual precipitation—will supercharge reservoir releases.
Yet plans for additional surface storage—Temperance Flat Dam, Sites Reservoir and Shasta Dam expansion—have been at a standstill for years. The projects would cost about as much as the high-speed rail from Shafter to Madera and about half as much as California’s Medicaid expansion on an annual basis.
Soon after California voters approved a water bond in 2014, the U.S. Fish and Wildlife Service dashed raising the Shasta Dam, claiming it would harm endangered species’ habitat. Yet the U.S. Bureau of Reclamation says more water storage could restore threatened salmon downstream. [aside: US Fish and Wildlife and US Bureau of Reclamation are each saying the opposite of each other here]