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Water

CA Drought Lifted, Snowpack at 15-Year High

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Governor lifts drought declarations from 2008, 2009

Snow removal near Mt. Lassen. (Photo: KNVN Chico-Redding).

Frank Gehrke summed it up: “Well, it has been a really crazy winter,” said the state’s chief surveyor of the Sierra Nevada snowpack.

Statewide averages from the season’s fourth survey Wednesday, shows water content at 165% of normal for April 1.

The latest survey shows statewide, water content of the Sierra snowpack is 165% of normal. Gehrke says it’s been about 15 years since there’s been this much snow on the ground at this point in the season. Earlier this month, some locations were reporting total seasonal accumulations equivalent to the height of a six-story building. Continue reading CA Drought Lifted, Snowpack at 15-Year High →

Government & Business, Water

Average Sierra Snowpack, More Water Allocated

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Photo: Gretchen Weber

Despite what might feel like an incessant onslaught of storms these past few months, the word from the Department of Water Resources’s fourth snow survey of the season is… average. Manual and electronic survey readings indicate that statewide, the Sierra snowpack water content is 106% of normal for this date. In the northern Sierra it’s higher, at 126% of normal, while the central and southern Sierra are at 92% and 105%, respectively.

The news was good enough for the DWR to increase its State Water Project allocation from 15% to 20%, but agency director Mark Cowin told reporters on a call Thursday that three years of drought and regulatory restrictions on Delta pumping to protect fish species will keep the allocations far below normal.  He said the final allocation, which is announced in May, will likely be between 30% and 40%, depending on April’s precipitation.  (Last year’s final allotment was 40%.)

“We’ve had a hit and miss nature to storms this winter, and that has left the State Water Project in not as good a position as we would like to be and perhaps worse than you would expect based upon those fairly good numbers regarding snowpack and precipitation,” said Cowin. “Remember that we started this winter with very poor carry over storage in most of our key reservoirs.”

While many reservoirs across the state, such as Lake Shasta, are at above average capacity for this time of year, others still have a ways to go.  The State Water Project’s principal reservoir, Lake Oroville, is currently at 47 percent capacity, which is just 60 percent of normal.   Cowin said that the difference between the two lies with where the snow fell this year.

“Clearly we’re going to have water shortages this year,” said Cowin.  “We’re all going to have to conserve water.  Even if we get to 30 or 40% allocation, those are still low numbers. The ethic of using water efficiently in California has got to be the normal course of business and not dependent on the weather forecast.”

Last month, the U.S. Bureau of Reclamation issued an updated allocation for its Central Valley Project customers that ranged from 25% to 75%.

Check recent levels of California’s major reservoirs on the map, below:

View KQED: California Reservoir Watch in a larger map

Water

Latest Snow Survey Offers Hope

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Frank Gehrke, left, weighs snow near Echo Summit, to measure water content. Photo: Molly Samuel
Frank Gehrke, left, weighs snow near Echo Summit, to measure water content. Photo: Molly Samuel

His clipboard doesn’t have quite same gravitas as a pair of stone tablets. Nonetheless, Frank Gehrke is sort of the Moses of California water. Once a month he comes down from the mountaintop with a pronouncement on the state of the snowpack in the Sierra Nevada. Today’s message: Whew.

The Department of Water Resources announced today that on average, the water content of California’s Sierra snowpack stands at 107% of “normal” for this date. The figure is derived from a combination of electronic sensors and manual surveys, including Gehrke’s, taken at various points along Highway 50. It’s the first time this season that the statewide average has clocked in above normal.

In the monthly DWR news release, Director Mark Cowin expressed some relief, while warning that the state is still struggling to overcome three abnormally dry winters prior to this one. DWR reports that Lake Oroville, the primary reservoir for the State Water Project, still stands at just 55% of it’s long-term average level for this date. Shasta Lake, however, the biggest reservoir on the federal Central Valley Project, is now above its normal level.

Cowin says the latest readings offer hope that water managers will be able to increase projected allocations to state water customers, currently set at 15% of requested amounts. DWR estimates that final allocations will be “in the range of 35-45%.” Over the past ten years, customers have averaged about two thirds of requested water. Farms often make up for shortfalls by pumping costlier groundwater.

Our interactive map shows the current status of California’s key reservoirs. We also have a short video that takes you into the field with Frank Gehrke, to see how he does his manual surveys.

Water

Storms Offer Big Boost to Sierra Snowpack

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For a more expansive analysis of California’s current water picture, and an interactive map of current reservoir conditions, see Dan Brekke’s drought update, posted earlier this week.

State water officials expressed “cautious optimism” after the season’s second survey of the Sierra snowpack.

After a series of Pacific storms dumped several feet of fresh snow on the mountains, today’s (officially the “February”) survey reveals that the snow’s average water content is 115 percent of “normal” for this date (compared to 61% of normal at this time last year).

Water managers say even so, there’s more catching up to do and they still can’t rule out a fourth consecutive year of relatively dry conditions. Nor have they re-evaluated earlier tight allocations planned for agricultural water this year. With a lot of the recent precipitation still locked up in the state’s “frozen reservoir,” Shasta Lake and Lake Oroville are both still hovering around half of their normal levels for this date.

According to today’s release from the Dept. of Water Resources:

“DWR’s early allocation estimate was that the agency would only be able to deliver 5 percent of requested SWP (State Water Project) water this year, reflecting low storage levels, ongoing drought conditions, and environmental restrictions on water deliveries to protect fish species.  The agency will recalculate the allocation after current snow survey results and other conditions are evaluated.”

By the way, if you’ve never had the chance to see how the “manual” component of the monthly snow surveys are done, take about four minutes and watch this video from 2008, when I joined surveyor Frank Gehrke at the Tamarack Flat survey site, off of Highway 50. This is not the site you usually see on the local news. That’s Phillips Station, chosen for media photo ops because it’s right off the highway. Getting to this site takes a little more doing, as you’ll see.

The Science

Sierra Snow: Scientists in Heated Agreement

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Loot from the recent invasion of email servers at the Climatic Research Unit (CRU) in Britain has raised questions about whether scientists who dissent from the prevailing views of climate research are being muzzled by their colleagues.

Snow on Mt. Whitney. Photo: USFS
Snow on Mt. Whitney. Photo: USFS

An interesting example of this arose this week in a report by Richard Harris for NPR’s All Things Considered. It’s worth a listen, if only for the back-and-forth between two climate scientists over snowfall in the southern Sierra Nevada mountains. John Christy of the University of Alabama, Huntsville, tells Harris about trouble he’s had publishing research that appears to counter the mainstream view that the Sierra snowpack is endangered. For a response, Harris goes to Philip Mote at Oregon State University, one of the scientists who reviewed Christy’s research.

Also interviewed are Gavin Schmidt of NASA and Judy Curry from Georgia Tech.

The head of the UN’s climate panel finally issued his own statement on the email flap, which was part condemnation of the hackers, part defense of the science and peer review process.

Water

Paddling to the Sea

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Jessie Raeder is Bay Area Organizer for the Tuolumne River Trust. More than 200 paddlers are expected to take to the river between now and June 7, for this river awareness relay. Raeder offers this dispatch from the starting line, near the headwaters in Yosemite National Park.

By Jessie Raeder

Paddle to the Sea got off to a roaring start over the weekend.  Melting snow caused by an early heat wave in the Sierras had the river pumping at much higher flows than rafters typically face. The Tuolumne is usually rated Class 4–but goes to Class 5 when flows get over 4000 cubic feet per second.   This weekend saw the river flowing at 7000 cfs! For a while it looked like we might have to cancel all the whitewater trips due to safety concerns, but in the end one trip did go on and needless to say it was an epic journey for our Paddle-to-the-Sea team.

A paddler takes on the Clavey. Photo:
A paddler takes on the Clavey. Photo: Patrick Koepele, Tuolumne River Trust

Meanwhile, an international team of 12 hotshot kayakers ran the Clavey River, a tributary of the Tuolumne and one of only three remaining free-flowing rivers in the Sierra.  The Clavey is a class 5+ river that’s rarely run and only by experts.

Paddle to the Sea is a three-week festival to foster stewardship of the Tuolumne River. Hundreds are joining in this epic journey from the Sierra to the Sea. Kayakers and rafters will begin on the upper stretches of the Clavey and Tuolumne Rivers, travel through the Central Valley where canoers take the lead, pass through the confluence of the Tuolumne and San Joaquin Rivers, and sea kayakers will finish the trip in San Francisco Bay.

A changing and increasingly unpredictable water supply will be the first way that most people in California experience climate change affecting their own lives.  Here in the Bay Area, tap water for 2.5 million people comes from the Tuolumne River, whose headwaters start with melting snow from the Lyell Glacier (picture attached).  That glacier is on the retreat, and more frequent droughts are expected throughout the Sierra.

Paddle to the Sea is meant to demonstrate that issues that affect one section of the river ripple up and down the watershed.   Bay Area water users share this resource with farmers in Modesto, anglers in Yosemite, the commercial salmon industry on the Pacific, and a host of native fish, plant, and wildlife species, many of which are endangered.

As population and demand for water continues to grow, California will be faced with many questions about how we use water, and where it will come from.  The Tuolumne River Trust is working to ensure that we turn to water efficiency and water recycling as much as possible–alternatives which are far more sustainable and renewable than continuing to take additional water from the Tuolumne River, which has been the solution most turned to in the past.

 

Water

Sierra Snow Season Ends with a Whimper

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Surveyor Frank Gehrke takes on last poke at the season's shrinking snow pack. Photo by Craig Miller.
Surveyor Frank Gehrke takes one last poke at the season's shrinking snow pack. Photo by Craig Miller.

When veteran snow surveyor Frank Gehrke stuck his aluminum tube into the thinning snow course at Phillips Station this morning, the “Mount Rose” snow gauge stopped dead a few inches in. He then withdrew a sad little cylinder of corn snow, about the size of a flashlight battery. There was barely a foot of snow left at this measuring station, 6,900 feet above sea level. Water content: 35% of normal. Yikes. Of course, that’s just one station among many surveyed on a monthly basis to help handicap the coming summer’s water supply.

The numbers are in for the season’s last snow survey: On average throughout the Sierra Nevada, water content clocks in at 66% of normal for this date. Last year at this time it was 72% of normal. The southern third of the Sierra came in at 61%.

So even with that hope-lifting late-season burst of precipitation that started in mid-February, we ended up even worse than last year–at least in terms of the snowpack. Some local reservoirs filled up nicely with the soggy spring. The trouble, says Gehrke, is that “The big ones didn’t.”

Some municipal water districts have vacillated on rationing plans for the summer. But the big state and federal systems that supply irrigation water to farms have largely stuck with their drastic cuts in allocations this year.

The bottom line, according to state water director Lester Snow:  “When combined with extremely dry years in 2007 and 2008, low storage in the state’s major reservoirs, restrictions on Delta pumping, a growing population and prediction of increasingly unpredictable weather patterns due to climate change, it is clear the problems facing California will persist beyond this year and this drought.”

Official drought proclamations have been a source of some controversy since the rain finally began falling in February. The Department of Water Resources has produced a statewide water plan and put it up for comment until June.

Water

Early Runoff More than Theory

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This post has been modified based on clarifications by the study’s lead author, which are outlined in her comment, below.

A recent study seems to confirm what many have already surmised: The spring melt from the Sierra snowpack is happening sooner.

To get a handle on the timing of mountain runoff, a team led by Iris Stewart of Santa Clara University pulled together data from 52 stream gauges up and down California. For her study, Stewart says she chose only water courses unaffected by dams and diversions, with at least 20 years of continuous data.

Stewart’s data shows that over the 60 years spanning 1948-2008; 80% of the gauges show the “stream pulse” that accompanies peak runoff, coming consistently sooner in the season–an average of about 10 days sooner, though at least one location had shifted up by more than a month. In fact, combining all of the metrics in the study, Stewart says only one gauge showed a later trend.

The trend seems remarkably consistent. Stewart says that despite a warming trend over the past ten years, she has not seen any acceleration of the trend within that period.

Stewart cautions that there’s more work to do on this and was reluctant to draw broad inferences from the study. Runoff in a particular stream is affected by many factors, including the elevation, slope, aspect (which direction it’s facing), vegetation cover and soil composition. Stewart says further study of these variables will better help identify the most vulnerable streams. But the latest results seem consistent with an earlier study in which Stewart found “earlier runoff on a continental scale.”

Scientists are concerned that as average temperatures rise, California’s mountains will see more rain, less snow–and what snow there is will melt off sooner. Reservoirs can only retain so much runoff at once, so if more of the “frozen reservoir” dissipates earlier in the season, farms and cities stand to be caught short of water before the rains return.

Stewart, an assistant professor at SCU’s Environmental Studies Institute, presented her findings this morning to researchers at the Pacific Climate Workshop (known as PACLIM, the conference does not have a website), a semi-annual gathering of climate scientists doing front-line research around North America. The conference in Pacific Grove is organized by the USGS office in Menlo Park.

Over the course of four days, about 60 researchers will hear findings on the climatic implications for fire, fog, glaciers, the ocean and wildlife, among other topics.

Water

Snowpack Buildup “Too little, too late”

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Frank Gehrke at Tamarck Flat last winter.
Frank Gehrke at Tamarack Flat last winter.

That’s how Frank Gehrke described the somewhat improved numbers in the latest Sierra snowpack survey. Gehrke has been trekking up to the snow courses for decades to do the seasonal surveys. Today, the statewide average for water content in the snowpack came in at 80% of normal for this date.

Northern Sierra locations clocked in a bit better at 84%, southern locations at 77%. These are an improvement over last month’s tally, when the state averaged only 61% of normal–but reservoirs are not filling fast enough to make up for the long, dry winter that preceded this recent string of storms.

Not that the recent rains haven’t helped. Oakland, Long Beach, Riverside and San Diego are among several spots that have now had at least 90% of their normal precipitation–and some local reservoirs have been catching up. But up in the Sierra, where it really counts for the Big Picture, they’re not catching up fast enough. The main holding “tanks” for the state’s two major water supply systems, Shasta Lake and Lake Oroville, are still at 60% and 55% of normal, respectively.

The recent storms have been relatively warm, too, with precipitation falling as rain all the way up to 7,500 or 8,000 feet. This is precisely the condition that climatologists have been warning about. Snow sticks to the mountain and makes its own reservoir, slowly releasing water well into the spring, as it melts off. But rain at those high elevations is double trouble. It runs off immediately into the rivers and also accelerates the snow melt. That means less water for later in the season, when we really need it.

That may be why the Governor didn’t wait around for today’s numbers. He went ahead and declared a statewide drought emergency on Friday, urging urban water users to cut consumption by 20%.

Power, Water

The End of Ag? Chu Drops a Climate Bomb

arizona-drought-small.jpgHigher temperatures and drier conditions could destroy California’s vineyards by the end of the century if Americans do not act fast to slow global warming, Secretary of Energy Stephen Chu said Tuesday in his first interview since joining the Obama cabinet.  Chu, a California native, warned that increased water shortages in the West and a loss of up to 90 percent of the Sierra snowpack are likely to have a severe impact on the state’s agricultural industries as well as California’s cities.

“I don’t think the American public has gripped in its gut what could happen,” Chu told the Los Angeles Times.  “We’re looking at a scenario where there’s no more agriculture in California.”

Californians may appreciate this kind of attention in Washington to what is shaping up as potentially the worst drought in the state’s history.  The California Department of Water Resources reports $308.9 million in agricultural losses last year due to drought in the state, and if January was any indication of what’s to come, that number will be even higher for 2009.  The Santa Rosa Press Democrat reports that grape growers in the counties of Sonoma and Mendocino are facing a difficult choice this month as they decide whether to use some of their reduced water allotments for frost protection. With such a rapidly dwindling supply, water used now could mean none for irrigation later in the season.

This morning on KQED’s Forum, California water experts discussed the direness of the situation and the probability of water rationing and other measures to deal with it.

The California Department of Water Resources website has extensive information about drought conditions and mitigation efforts across the state, including this fact sheet updated for January 2009.

Photo by Reed Galin