Department of Water Resources

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California Winds Up “Wet” Season on the Dry Side

But communities that depend more on rain, less on the snowpack are looking good

Craig Miller

In mid-January, much of the Sierra remained snowless.

Despite what felt like a late-season deluge, this will go down as a dry winter in California’s record books.

The season’s final survey of the Sierra snowpack by California water officials confirms that even heavy spring rains and fresh mountain snow as recently as last week didn’t make up for a late start to the rainy season and one of the driest Decembers on record. Today’s survey finds water content of the mountain snow at just 40% of the long-term average. That puts four out of the last five years on the dry side, though last year was a gullywhumper. Continue reading

Keeping Central Valley Crops and People Safe From Floods: A Costly Proposition

Big plans to revamp the Valley’s piecemeal flood management system…if there’s money for it

Now that the state’s revamped Central Valley Flood Protection Plan (big PDF) is out for public perusal, the question is whether the political will — and the cash — will be there to make it happen.

David McNew/Getty Images

California's status as an agricultural powerhouse is largely due to the fertile lands in the Central Valley, which are also prone to floods.

The Sacramento and San Joaquin river basins run through the valley and can overflow their banks threatening more than a million people and an estimated $69 billion in assets, according to the report. The current flood management system has been in place for about a hundred years and was designed specifically to keep water from the rivers off the land so that people could grow crops. Now the system has varied uses including conservation of habitat, water supply and water quality. The old system really isn’t up to the job anymore and almost everyone agrees that it will take a serious investment to bring it up to snuff.

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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

Soggy Mountain High: Big Start for Sierra Snowpack

Frank Gehrke conducting last year's first snow survey of the season. (Photo: Gretchen Weber)

All the wet weather that’s been drenching much of the state has left the Sierra Nevada with an extra-thick blanket of snow, which has water officials optimistic about the state’s water supply for 2011.

Using a combination of manual and electronic measurements, the state’s Department of Water Resources conducted its first snow survey of the season on Tuesday, and found the water content of the state’s snowpack at 198% of normal for this time of year.   Last year at this time, the statewide average was just 85% of normal.
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…And It’s Not Even Winter Yet

Snow drifts at Squaw Valley last winter. (Photo: Gretchen Weber)

Good news for cities, towns and farms across the state that rely on the State Water Project: Today California’s Department of Water Resources doubled its projected 2011 deliveries of water from its initial 25% estimate to 50% of amounts requested.

Fifty percent doesn’t sound like much but compared to last year, when the initial projection for 2010 was a record-breaking low of five percent, this year is off to a pretty soggy start.  These allocations tend to climb throughout the season, so the 25 million Californians who rely on this water could actually see much higher numbers as the winter progresses.  2010 ended up with a 50% allocation despite its conservative early estimates.

Statewide, remote sensing indicates the mountain snowpack is 122% of normal for this date. As of Wednesday, the northern Sierra had already received nearly half its “normal” precipitation for the entire water year, which runs from October 1 to September 30, according to DWR.

And it looks like more of the same for the near future.  Meteorologists are predicting up to 15 feet of new snow for parts of the Northern Sierra by the middle of next week.

State Water Picture Improves

If you’re counting on water from the State Water Project, this year is at least starting off better than the last couple.

For the farms and towns that depend on deliveries from the SWP, the outlook for the coming year is better than in recent years, which is not to say ideal.

State water managers today made their preliminary estimate that customers would get one quarter of the water requested from the system. That beats last year’s initial estimate of five percent–the lowest on record. Mark Cowin, who heads the state Department of Water Resources, says these early estimates are intentionally stingy:

“Over the past few dry years, CA has made good progress in improving our ability to conserve water,” Cowin told reporters in a conference call today, but cautioned that “We must continue to promote an ethic of using water efficiently—regardless of  the day-to-day outlook for water supplies.”

But Cowin says that between the wet spring and early start to the rainy season this fall, chances are good that the initial 25% projection will rise.

A key reservoir on the system, Lake Oroville, stands at more than three-quarters of its average for this time of year, whereas last year at this time, it was only about half full. By the time the water year was winding up, DWR officials had raised the allocation to 50%. They added that with average precipitation the rest of the way, customers could end up with about 60% of their hoped-for deliveries in 2011. So far this season, precipitation is running ahead of the long-term average.

You can check on how the state’s major reservoirs are doing throughout the year, with our interactive map.
View KQED: California Reservoir Watch in a larger map


View KQED: California Reservoir Watch in a larger map

Water in the State Water Project, like the federally run Central Valley Project, comes in large part from the mountain snowpack of the Sierra and lower Casdade ranges. Growers typically make up for shortfalls by pumping more groundwater.

Average Sierra Snowpack, More Water Allocated

Gretchen Weber

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

California Water Update: A Mostly Adequate Year

87760251Almost everywhere you look this week, California is dry. By which we mean the state is experiencing the first truly warm, rainless week since a series of Pacific storms blew through the state in mid-January.

Hydrologists for the state Department of Water Resources and the federal California-Nevada River Forecast Center expect the warm temperatures to trigger the first significant surge of snowmelt for the season. With slightly above-average snowpacks in the Sierra Nevada, that should help continue to raise reservoir levels. Our 2009-2010 rainy season is likely to go down in water history as adequate–short of hopes for a wet year but an improvement on the past three winters, which were much drier than average.

Admittedly, that’s the view from the city, where we get our water out of taps and garden hoses. The picture for agricultural users is not nearly as bright, as we were reminded earlier this week.

On Tuesday, the U.S. Bureau of Reclamation issued an updated allocation for its customers in the Central Valley. The bureau offered a good news-bad news scenario. For CVP customers north of the Sacramento-San Joaquin Delta, the news was mostly good. Agricultural contractors there will get at least 50% of promised deliveries this year; municipal and industrial customers will get 75%. South of the Delta, the news is not so good. Municipal and industrial users will get 75%, but farm customers are guaranteed just a quarter of the water they want.

That 25% zone south of the Delta includes the Westlands Water District and other areas on the west side of the San Joaquin Delta that have suffered severe water shortages, due mostly to the state’s prolonged dry spell and, less directly, to restrictions imposed on Delta pumping to protect Delta smelt and Chinook salmon.

That’s the same area for which Sen. Dianne Feinstein tried to secure extra water this year–even if it meant overriding provisions of the Endangered Species Act. Feinstein’s effort to attach a water amendment to a federal jobs bill failed, but the move apparently prodded the Department of the Interior–the parent agency of the Bureau of Reclamation–to try to find more water for Westlands and its neighbors. This week’s allocation announcement included assurances that the department is still working to secure additional water for west side farmers.

The state Department of Water Resources, which also ships water from the Delta to customers in the San Joaquin Valley and beyond via the California Aqueduct, also issued an updated allocation announcement this week. The department said that for now it’s sticking with its guarantee of 15 percent of requested deliveries this year.

Why such a low figure? The department says it’s because of continuing “poor hydrological conditions” in the Feather River drainage that feeds the State Water Project’s principal reservoir, Lake Oroville. The main symptom of those conditions is the lake’s storage level, now just 57% of average for mid-March. For contrast, look at California’s main federal reservoir, Lake Shasta, less than 100 miles away from Oroville as the crow flies. It’s got 104% of average storage for the date (not to be confused with percent of capacity).

Here’s my amateur, off-the-cuff runoff-watcher’s observation of what’s behind the difference: The Shasta drainage, which captures the upper reaches of the Sacramento, McCloud and Pit rivers as well as lesser streams, has benefited from several storms since mid-January that dumped heavy rains throughout the watershed. Those same storms have dropped lighter amounts of rain further south and east, including over the Feather watershed. The same effect can be seen in the American River basin, which flows into Folsom Lake. A month or so of intense precipitation last year eventually filled the lake; lighter rains this year have led to lower-than-average storage levels in Folsom (84 percent as of this week).

The final word on the water season, of course, will come from the Sierra snowpack and runoff. Stay tuned for the snow melt.

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

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.

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%.