Craig Miller

Given the forecast for the final week of February, now it really is down to a “March Miracle” to salvage the California water season.

So this time they didn’t even wait for the next snow survey. Water managers are pulling back on estimates of how much water they’ll deliver to contractors on major water projects. With winter precipitation running about half of normal, today the California managers set probably deliveries at half of what contractors (mostly irrigation districts) on the State Water Project are asking for — that’s ratcheted down from 60%.

Likewise the federal Bureau of Reclamation announced some skimpy allocations for its Central Valley Project, with some pegged as low as 30% of requests.

So how dry are we? Officials at the state Department of Water Resources sum it up this way:

Water Year (October 1-September 30) runoff from rain and snow is forecasted to be far below average in both the Sacramento River and San Joaquin River systems.  The median runoff forecast of 9.4 million acre-feet for the Sacramento River system would be the 16th driest in 106 years.  The February 1 median water year runoff forecast of 3.2 million acre-feet for the San Joaquin River system would be the 21st driest in 111 years.  Average runoff is 18.3 million acre-feet for the Sacramento system, and 5.9 million acre-feet for the San Joaquin.

The good news is that major reservoirs around the state are still hovering at about their normal levels for this time of year, thanks to a sustained soaking last winter. But with scant expectations for what remains of this winter, that “carry-over” will have to bail out the state this summer.

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.

We’ve updated our interactive map, showing the status of major reservoirs around the state.

View KQED: California Reservoir Watch in a larger map

Steve Nemeth, a Water resources engineer for DWR, says forecasts for spring runoff are equally cheery for virtually all Sierra watersheds, from the Yuba River south.

And another storm is due in tomorrow.

Of course, no silver lining would do without a dark cloud (that’s a bit confusing since in California, a dark cloud is a silver lining). The snow survey comes on the heels of a new report that suggests the long, long-term outlook for the southwestern US may be one of “periods of aridity lasting centuries to millennia,” if the distant past is prologue. The conclusions, based on studies of sediments from northern New Mexico, appears in the journal Nature.

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.

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

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