snow survey

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Snow Survey Says: It Could Have Been Worse

Thanks to last year’s wet winter, California’s reservoirs are still in good shape

Molly Samuel

In January of this year, snow was still sparse at high elevations in the Sierra Nevada.

Researchers from the Department of Water Resources conducted their April manual snow survey today. It’s the most important snow survey of the season, because it’s supposed to capture the Sierra snowpack at its peak. The DWR found that statewide, snow water content is 55% of average for this time of year.

Still, it could have been worse. The previous manual snow survey, which took place on February 28, measured snow water content at only 30% of normal for that date. So the rain in March did help.

“This was certainly a moderately good March at least,” Jeanine Jones, the Interstate Water Resources Manager at the DWR told me. “But the downside is that we are now getting outside of our peak precipitation window. On average about 75% of statewide precipitation comes between November and March.”

Continue reading

Snow Survey May Portend a Dry 2013

Skimpy Sierra snowpack may take a while to show up in water supplies

snow Tahoe Sierra California water

Tyche Hendricks/KQED

After a record dry December, there's finally snow on the ground near Soda Springs, at Lake Tahoe.

This morning’s snow survey (PDF) didn’t turn up any big surprises. As remote sensors foreshadowed, water content in the Sierra snowpack is 37% of normal for this time of year, and less than a quarter of the average for April, which is when the snowpack is usually at its peak before it begins melting and filling up California’s reservoirs.

What’s worrisome about that, according to Jeanine Jones, Interstate Resources Manager at the Department of Water Resources, is that about half of California’s annual precipitation typically falls between December and February, months that are mostly already behind us. “So where we are this year is: November was dry, December was close to record dry, January was maybe half of average,” Jones told me. “And currently the forecast for the first  ten days or so of February is essentially dry.” Continue reading

Sierra Snow Survey: Lots of Water but No Records

Snowy trees in Truckee, in February. (Photo: Lauren Sommer)

Surveyors from the Department of Water Resources strapped on their skis today and headed out to measure the status of the Sierra snowpack for the fifth and final time this season.  As expected, they reported good news for the state’s water supply.

It’s been a big year for the snowpack – the biggest since 1995 – and the snow’s water content is about 180% of what’s “normal” for early May. The spring melt has already begun, so there’s less snow than there was month ago.  Historically, early April is when the snowpack is at its peak, as it was this year.  And yet, the current water content of the snowpack is still 50% higher than the historic average for April first.

All this water has prompted officials to project water deliveries of 80% of requests from farms and towns served by the State Water Project this year.  That’s the highest percentage since 2006. Last year just 50% was delivered.

And yet when I asked DWR snow survey master Frank Gehrke if this year’s snowpack was record breaking, he chuckled a little and said, “Not even close.” Continue reading

Snow Surveys of the Future

A white fir outfitted with snow sensors in the Southern Sierra Critical Zone Observatory. (Photo: Sasha Khokha)

Trying to interview guys who wear backcountry skis to work can be tough…especially when trudging behind on snowshoes with a pack full of recording equipment. But my visit to the Southern Sierra Critical Zone Observatory was worth the slog.

It’s a patch of forest at about 6,000 feet near Shaver Lake in the Southern Sierra, in what’s known as the rain-snow transition zone. The snowpack at this elevation is likely to be the first to reflect climate change as temperatures warm and snow turns to rain. Scientists at UC Merced’s Sierra Nevada Research Institute, in conjunction with UC Berkeley, have developed new, high tech sensors to intensively monitor snow melt and runoff here. Continue reading

Burgeoning Snowpack Sweetens Water Outlook

A wet and wild February provided a huge boost to California’s water outlook

An unusually dry January started some folks thinking that maybe the tap had been shut off for this season. But last month winter came roaring back as Pacific storms brought epic snowfalls to the Sierra. The result: Today’s monthly survey shows the water content of the mountain snowpack at 124% of normal for this date–and even above its normal level for April first.

Check current reservoir levels with our interactive map, below.

Major reservoirs are also above their normal levels for early March. But it still doesn’t mean that contractors on the State Water Project will get all the water they ask for. Officials say they still expect deliveries to come in at about 60% of the volume requested. That’s a number that typically gets adjusted throughout the winter. Continue reading

Playing the State Water Lottery

Craig Miller

Photo: Craig Miller

I don’t know Mark Cowin, the director of the state’s Department of Water Resources. I haven’t even met the man, in person. But after listening to and reading his pronouncements about the state’s water supply, I’d guess he’s a guy who would barely crack a smile if he found himself holding a winning lottery ticket. I hazard that opinion because even after today’s great news about the Sierra snowpack–which is a little like finding out the state has won its annual water lottery–what Cowin emphasizes is that California isn’t out of the woods after the dry spell of 2007-2009. But more about that to follow. First, the details on the DWR’s final Sierra snow survey.

DWR announced on Friday that statewide, the water content stored in the Sierra snow is at 143% of normal for the date; 188% in the northern Sierra, 121% in the central mountains, and 139% in the southern reaches of the range. Up and down the Sierra, those figures are more than double the levels of the past two years, and are up to seven times as much as surveyors found in the bone-dry spring of 2007.

Last week, the Department announced it would increase allocations from the State Water Project to 30% of the amount requested from 29 urban and agricultural customers. Today’s snowpack news prompted the department to say that it’s likely to increase deliveries. How much? “Only marginally,” Cowin said in a phone interview this afternoon. “We’ll have to run the numbers, and we’ll probably make that determination in the next week or two.”

How much water will State Water Project customers get, eventually? Let’s run some numbers of our own.

The main reason the department cites for the very tight supply in the midst of a year of “normal” precipitation is the continuing below-average levels at California’s biggest state-owned reservoir, Lake Oroville. As of Friday afternoon, the lake is at 72% of normal for the date and about 60% full. But the stats that Cowin’s water geeks are crunching aren’t about the level today, but where they guess it will be as runoff begins to pour from the snow-blanketed mountains through the Feather River watershed into Lake Oroville. DWR officials have insisted that it believes runoff will be held down because of dry conditions caused by the last three drought years. You wonder if they’ll still believe that after assessing the impact of an unusually wet April and its impact on the snowpack.

While pondering that, here are some other numbers to consider if you want to play what I’ll call the State Water Project Allocation Game:

  • After running far below its 2008-2009 levels all season, the water storage in Lake Oroville caught up and passed year-ago levels this week. The lake’s storage has increased six percent—more than 150,000 acre-feet—since last Friday.
  • As noted above, this year’s snowpack is better than double last year’s.
  • Last year, the state delivered 40 percent of requested water shipments to its SWP customers. The average allocation for the past 10 years is 68 percent.

Considering all of the above—last year’s deliveries, the snowpack, the sudden late-season surge in Lake Oroville’s levels—it’s a no-brainer that water deliveries will at least match last year’s 40 percent. The question is whether the allocation will go higher. All Cowin would say on that subject today is that he thinks that 45%, the amount DWR described two months ago as the upper limit for shipments this season, is still accurate.

But Cowin did say, as he has more and more frequently of late, that a preoccupation with the this year’s water level misses the point about California’s water reality.

“That’s why we’re so concerned when we get the black and white question, ‘Is the drought over,’” he said. “We are in a period of long scarcity in California. We have no idea what next year’s water supply picture will look like. It’s possible we could have two or three more dry years in a row. So we’re trying to get a message out that we need to have a new attitude about how we use water in California, and it shouldn’t depend on this week’s outlook. We need to conserve water just as a way of life.”

If you want to explore the state’s water supply picture for yourself, check out our California Reservoir Watch map, below:

View KQED: California Reservoir Watch in a larger map
View KQED: California Reservoir Watch in a larger map

Latest Snow Survey Offers Hope

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.

Storms Offer Big Boost to Sierra Snowpack

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.

No Surprises in Season’s First Snow Survey

California’s Department of Water Resources (DWR) today released the first of the season’s surveys of snow conditions, an indicator of how much runoff we can expect to fill reservoirs in the spring.

Snow surveyor Frank Gehrke at the Phillips Station survey site. Photo: Gretchen Weber

Snow surveyor Frank Gehrke at the Phillips Station survey site. Photo: Gretchen Weber

At the Phillips Station survey site, just off U.S. Highway 50, lead surveyor Frank Gehrke found about the conditions he expected; water content of the accumulated snowfall there weighed in at 75% of normal. For the five survey sites in the region defined by DWR as the Central Sierra, and for all Sierra survey sites combined, water content was a slightly healthier 85%. While the average represents a slight improvement over last year at this time, when statewide water content clocked in at 76%, DWR officials emphasized that conditions are still below normal. And with the accumulating effects of three prior relatively dry years, some major reservoirs remain at low levels. A sobering example from today’s DWR release:

“Lake Oroville, the principal storage reservoir for the State Water Project (SWP), is at 29 percent of capacity, and 47 percent of average storage for this time of year.”

With several months remaining in the state’s traditional “wet” season, the January survey is perhaps the least reliable indicator of final runoff. According to Gehrke, the season can “go either way from here.”

In a 110-page California Drought Update just released, DWR wrote that:

“Impacts being experienced in the present three-year drought are relatively more severe than those experienced during prior dry conditions – such as the first three years of the 1987-92 drought.”

As such, the agency says it “will move aggressively forward to plan for a potentially dry 2010…”

In February Governor Schwarzenegger declared a drought state of emergency for nine counties that is technically still in effect, though appeals to the federal government for disaster relief have gone unanswered. The Governor has also called on all urban water consumers to cut back their use by 20%.