Water & Drought

Melting snow, water releases and La Niña complicate California’s drought picture

See how Jerry Brown measured California's bleak snowpack in 2015

On April 1, 2015, Gov. Jerry Brown attended a routine snow survey at 6,800 feet in the Sierra Nevada, near Echo Summit on Highway 50 along the road to Lake Tahoe. The April survey is an annual ritual, marking the end of the winter season, in which
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On April 1, 2015, Gov. Jerry Brown attended a routine snow survey at 6,800 feet in the Sierra Nevada, near Echo Summit on Highway 50 along the road to Lake Tahoe. The April survey is an annual ritual, marking the end of the winter season, in which

First, the good news: This winter, much of the Sierra had a near-average snowpack. Now, the bad news: It has melted early.

Word of the vanishing Sierra snowpack, which usually helps replenish reservoir levels later in the summer, arrives amid uncertainty over how California’s dams will be managed in coming months to protect endangered fish. It also comes at a critical juncture for urban water officials across the state. Wednesday is their deadline to submit updated drought conservation plans that lay out projections of how much water will be available to customers over the next three years.

Federal officials late last week signed off on a plan that would release more water from Shasta Dam through June. The decision came after 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 Friday 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, bureau spokesman Shane Hunt said Monday.

“We need to start increasing releases to meet our commitments to our contractors,” Hunt said.

News of the temporary plan led to sighs of relief throughout the state’s agricultural industry, as it means 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 as they head into the hottest months. Meanwhile, environmentalists worry that fish won’t get the water they need to stave off extinction.

Hunt said he hopes an agreement that strikes a balance between those interests will be finalized sometime this week.

After two years of fallowing fields, rice farmers in the Sacramento Valley significantly ramped up planting this spring. A series of heavy storms this winter and early spring fueled expectations that water deliveries were returning to normal. But some farmers have said Sacramento River flows are lower than expected, leaving them worried they won’t have enough water to sustain their crops. More water from Shasta could help.

The additional June flows also could help San Joaquin Valley farmers reliant on water pumped from the Sacramento-San Joaquin Delta.

“It’s not just good for us,” said Johnny Amaral, deputy general manager for the sprawling Westlands Water District in the San Joaquin Valley. “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 is 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.

Once the water is released, it can’t be put back. The damage done to the fish is irreversible, particularly if they go extinct.

Jon Rosenfield, Bay Institute of San Francisco

The first proposal involves keeping a substantial amount of water in Shasta Lake until summer to protect juvenile winter-run Chinook. The second plan aims to rescue the Delta smelt, which also teeter on the brink of extinction, by letting more water flow to the Pacific Ocean through the Sacramento-San Joaquin Delta.

The plan could have implications for Folsom Lake, since it may mean a second year in which regulators draw more heavily on the Sacramento region’s primary drinking water reservoir to help control salinity levels in the Delta. Local water officials say they anticipate being able to serve all their customers’ needs, even if the lake dips.

State and federal dam operators are required to maintain flows that ensure the survival of downstream fish. They are also required to ensure that enough freshwater flows through the Delta to keep seawater from rushing into the estuary and compromising salinity levels. The freshwater pumped from the Delta provides irrigation for millions of acres of farmland in the San Joaquin Valley and drinking water for 25 million residents.

Last week’s decision to release more water from Shasta comes amid fairly bleak news from state officials about the snowpack that officials had hoped would help sustain reservoir levels later in the year.

The Sierra snowpack has all but disappeared, state officials say. The vast majority of the Sierra has no measurable snow. The snowline in Yosemite National Park sits at roughly 10,000 feet, mostly covering 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.

Recent weather conditions and rising temperature have unleashed gushing waterfalls in Yosemite National Park. The waterfalls will peak sometime in May. And some of the seasonal ones will likely run until mid to late summer, according to a park rep

It has not been abnormally warm in the Sierra. At the South Lake Tahoe airport, the average high temperature in May was 61 degrees. So far in June, it has been 72 degrees. In both months, temperatures were essentially even with the historical average, federal data show.

At the Yosemite National Park ranger station, the average high temperature was 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 5 inches of precipitation between April 1 and Monday, a couple of inches below average, state data show.

Other signs don’t bode well for the state’s drought situation. Forecasters announced earlier this month that California faces a 75 percent chance of a potentially dry La Niña weather pattern during the fall and winter.

California continues to be 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.

Kelly Redmond, regional climatologist with the Western Regional Climate Center at the Desert Research Institute in Reno, said the recent conditions might be considered the new normal amid climate change.

“As a harbinger of what we might be seeing in the future,” he said, “this year as well as last year are not bad examples to be looking at.”

Still, Hunt, the Bureau of Reclamation spokesman, said that the state is in far better shape this year than it was last year, and there’s hope that the water in the Sacramento Valley reservoirs could last into 2017.

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.

“We’re hoping we can work through everything and keep some water in Folsom,” Hunt said. “I’m optimistic right now.”

Ryan Sabalow: 916-321-1264, @ryansabalow

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