[env-trinity] Melting snow, water releases and La Nina complicate California’s drought picture

[Tom Stokely]

http://www.redding.com/news/local/melting-snow-water-releases-and-la-nina-complicate-californias-drought-picture-35b82d9b-9b05-5f05-e0-383707081.html
LOCAL NEWS
Melting snow, water releases and La Nina complicate California’s drought picture
Posted: June 20, 20160 CommentsBy Ryan Sabalow and Phillip Reese, Sacramento BeeFederal officials have begun releasing more water from Shasta Dam following nearly two weeks of pressure from California's powerful farming lobby and members of Congress who argued that too much water was being held back to protect endangered fish.The U.S. Bureau of Reclamation and federal fisheries officials on June 17 adopted a temporary plan that would increase the amount of water rushing down the Sacramento River below Shasta Dam from 8,000 cubic feet per second to 9,000 for the rest of June, spokesman Shane Hunt said Monday."We need to start increasing releases to meet our commitments to our contractors," Hunt said.The news led to sighs of relief throughout the state's agricultural industry, since it means there will be more water for crops in the short term, particularly for rice farmers in the Sacramento Valley.However, Federal officials still haven't formalized a plan to protect endangered salmon and smelt later this summer by managing water behind Shasta and other Sacramento Valley dams. The lack of a formal plan has left growers anxious they won't get enough water going into the hottest months. Environmentalists worry that fish won't get the water they need to stave off extinction.Hunt said he hopes an agreement will be finalized sometime this week.After two years of fallowing fields, rice farmers in the Sacramento Valley significantly ramped up planting this spring. Heavy storms this winter fueled expectations that water deliveries were returning to normal. But some farmers have said Sacramento River flows are lower than expected, and they're concerned about having enough water to sustain their crops. More water from Shasta could help.The additional flows also could help San Joaquin Valley farmers reliant on water pumped from the Sacramento-San Joaquin Delta."It's good news for the entire state," said Johnny Amaral, deputy general manager for the sprawling Westlands Water District in the San Joaquin Valley. "It's not just good for us. It's good news for the people who drink water or use water. ... I would say level heads have prevailed."Environmentalists countered that increased releases from Shasta could threaten endangered fish that need cool water in the Sacramento River to survive. Maintaining a deeper pool of water behind Shasta makes for colder water. The idea is to release that colder water later in the summer and early fall, when critically endangered winter-run salmon make their annual return to their spawning grounds below the dam. Releasing water now could mean less cool water available later.The past two summers, excessively warm water in the Sacramento River killed off nearly all of the juvenile Chinook. Scientists say a third year of die-offs could mean the extinction of the winter-run as a wild species.Jon Rosenfield, a conservation biologist at the nonprofit Bay Institute of San Francisco, said not maintaining cool temperatures in the Sacramento River "would push the winter run Chinook salmon very close to extinction."He noted that the U.S. Bureau of Reclamation has confidently increased water releases from Shasta in prior years, only to later fail to hold temperatures down."I'm dubious that they actually know they have enough water," Rosenfield said. "It's an irreversible thing — once the water is released, it can't be put back. The damage done to the fish is irreversible, particularly if they go extinct."The increase in Shasta releases follows a June 9 letter from 15 members of Congress from California urging the Obama administration to reject two dam-management proposals they said could hurt the state's water supply.The first proposal involves keeping a substantial amount of water in Shasta Lake until summer to protect juvenile winter-run Chinook salmon. The second plan aims to rescue the Delta smelt, which also teeter on the brink of extinction.The plan for Shasta could have implications for Folsom Lake, since it may mean a second year in which regulators draw more heavily on Sacramento region's primary drinking water reservoir to help control salinity levels in the Delta.The Bureau of Reclamation, which operates dams in the federal government's Central Valley Project, is considering letting more water flow to the Pacific Ocean through the Sacramento-San Joaquin Delta this summer to protect the smelt.State and federal dam operators are required to maintain flows that ensure downstream fish survive. They're also required to ensure that enough fresh water flows through the Delta to keep seawater from rushing into the estuary and compromising salinity levels. The fresh water pumped from the Delta helps provide irrigation for millions of acres of farmland in the San Joaquin Valley and drinking water for 25 million residents.Friday's action to release more water from Shasta comes amid fairly bleak news from state officials about the snowmelt, which provides a substantial portion of the state's summer water supply. In addition, federal forecasters say California faces a 75 percent chance of a potentially dry La Niña weather pattern during the fall and winter.The Sierra snowpack has all but disappeared, state officials say. The vast majority of the Sierras has no measurable snow. The snowline in Yosemite National Park sits at roughly 10,000 feet, mostly covering just a portion of the eastern side of the park.Normally at this time of year, the Sierra has an average of about 3.3 inches of snow-water content. As of Monday, it averaged 0.1 inches.It has not been abnormally warm in the Sierras. At the South Lake Tahoe airport, average high temperatures in May were 61 degrees; so far in June they have been 72 degrees, almost even with the historical average, federal data show.At the Yosemite National Park ranger station, average high temperatures were 72 in May and 81 so far in June, also on par with historical averages.But the mountains did not get much snow after the start of April. The Central Sierra received the equivalent of about five inches of precipitation between April 1 and Monday, a couple of inches below average, state data show.Late season precipitation can keep snowpack around longer. On April 1, 2010, the central Sierra had a similar amount of snow as it did on the same date this year. But after 11 inches of precipitation in April and May 2010, snow lingered that year into early July.Lake Shasta and Lake Oroville, the state's two largest reservoirs, remain above average levels for this time of year, state figures show. Folsom Lake and Don Pedro Reservoir are near average levels. All told, eight of the state's 12 major reservoirs are above 75 percent of average for this time of year.All of California is abnormally dry, according to the National Drought Mitigation Center. Almost 43 percent of the state is either in extreme or exceptional drought. One year ago, about 71 percent of the state was in extreme or exceptional drought.The most parched area stretches from around Fresno County in the north to Orange County in the south. Most of Sacramento County is in severe drought, one step below extreme drought.Hunt, the Bureau of Reclamation spokesman, said that the state is far better shape this year than it was last year, and there's hope that the water in the Sacramento Valley reservoirs could carry over to next year."We haven't had that since probably 2011," Hunt said. "We're hoping we can work through everything and keep some water in Folsom. I'm optimistic right now."
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