Drought

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Running Drier: The Colorado 50 Years Out

A new federal study says the Colorado River may carry 9% less water by 2060.

Lake Mead, the Colorado River's largest reservoir in May, 2010 (Photo: Gretchen Weber)

The Colorado River is a critical source of water for more than 30 million people throughout the western United States. California alone gets more than a trillion gallons of water each year from the Colorado. But over the years, recurring droughts and the growing demands of urban populations have stressed the river system, which the Bureau of Reclamation now characterizes as “over-allocated.”  In efforts to plan for the region’s future water needs, the agency, in collaboration with Western states, has undertaken a two-year study to look at what lies ahead for the river and the cities, farms, and families that rely on it.

On Monday, the agency released the first interim report of the “Colorado River Basin Water Supply & Demand Study,” which projects changes in the river’s flow under four different scenarios. A model that incorporates predicted impacts of climate change shows a nine percent reduction in the Colorado’s flow within 50 years.  The study also projects more frequent and more severe droughts throughout the system. Continue reading

CA Drought Lifted, Snowpack at 15-Year High

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

The Science of Reconstructing Past Climate

To find out what tree rings are telling us about droughts in the Colorado Basin, and to get some current perspective on the current eleven-year drought in the region, listen to my radio story for The California Report and view the slide show of my journey to the region. — Gretchen Weber

With cores from trees like this one, scientists have been able to reconstruct more than 1,000 years of climate history in this region. (Photo: Gretchen Weber)

Abbie Tingstad is a paleoclimatologist whose doctoral work at UCLA involved reconstructing climate in the Upper Colorado River Basin, using tree rings and lake sediments.

By Abbie Tingstad

Unlike biology, chemistry, or most mainstream sciences, it’s hard to envision what someone who studies paleoclimatology actually does. I run into a lot of blank stares at dinner parties. So I’ve started describing the field as “climate forensics.”

Paleoclimatology and forensics of the Law & Order or Bones variety share the basic goal of reconstructing something that has happened in the past. In the latter, of course, the sequence of events that led to a crime is put together. In the former, researchers identify past variations in climate.  These sciences also have quite a lot in common when it comes to the basic methodology: Continue reading

California Counties Face Water Crunch

More than eight out of ten California counties will face frequent water shortages within 40 years. That’s the conclusion of a report released this week by Tetra Tech for the Natural Resources Defense Council.

See complete map of California, below. (Image: NRDC)

“This report is a real eye opener,” says Theo Spencer, senior advocate for the NRDC’s Climate Center. “It shows the toll climate change will take on the water resources in the U.S.”

Tetra Tech projects that climate change will exacerbate water problems in more than a third of counties across the US. In California, the outlook is worse. Forty-eight counties (83%) will be at risk by 2050, and 19 counties are on the critical list, those the report describes as under “extreme risk.” Only ten counties, mostly at the northern end of the state, were assigned to the low-risk category.

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

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

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%.

Updated: Disaster Status Sought for Valley

Five days after filing it, Governor Arnold Schwarzenegger was still awaiting some response from the White House to his request for a federal disaster declaration, to address drought conditions in Fresno County.

Meanwhile, the Washington bureau of the McClatchy newspaper chain (which includes the Fresno Bee) reports that the request is something of a longshot.

The Governor made the request last Friday, one day after he faced a tense gathering in Fresno, where water issues upstaged even the precarious condition of state finances, and shortly after a meeting with farmers in Mendota.

The governor has had a standing statewide drought emergency in effect since February. Friday he signed an executive order freeing up state resources to help ease drought-related impacts. A federal declaration would allow affected businesses to apply for federal aid. President Obama has since signed several other disaster declarations last week, in response to storms in Missouri, wildfires in Oklahoma and other incidents.

Parsing the White House Climate Report

At least one researcher cited in the 196-page climate impacts report issued this week by the Obama administration is not impressed with the final product. Roger Pielke of the University of Colorado’s Center for Science & Technology Research has written a blog post critical of the report and in particular, the way in which his work was interpreted. If you’d rather not plow through the entire post, John Tierney has an overview of Pielke’s critique on his blog for the New York Times.

California heat wave, from the Aqua satellite. Image: NASA

2004 California heat wave, from the Aqua satellite. Image: NASA

The report was arguably the first to break down both observed and projected effects of climate change into coherent regional summaries. For the purposes of the report, California was considered part of the Southwest region, which included states as far east as Colorado and New Mexico.

Not surprisingly, many of the points raised in the Southwest section (beginning on p. 129) have to do with water supply. Most have been reported or discussed in our Climate Watch coverage, either here or in our radio reports. Selected “highlights” include:

- Past climate records based on changes in Colorado River flows indicate that drought is a frequent feature of the Southwest, with some of the longest documented “megadroughts” on Earth.

- The prospect of future droughts becoming more severe as a result of global warming is a significant concern, especially because the Southwest continues to lead the nation in population growth.

- Human-induced climate change appears to be well underway in the Southwest. Recent warming is among the most rapid in the nation, significantly more than the global average in some areas.

- Projections suggest continued strong warming, with much larger increases under higher emissions scenarios compared to lower emissions scenarios. Projected summertime temperature increases are greater than the annual average increases in some parts of the region, and are likely to be exacerbated locally by expanding urban
heat island effects.

- Water supplies in some areas of the Southwest are already becoming limited, and this trend toward scarcity is likely to be a harbinger of future water shortages. Groundwater pumping is lowering water tables, while rising temperatures reduce river flows in vital rivers including the Colorado.

- Projected temperature increases, combined with river-flow reductions, will increase the risk of water conflicts between sectors, states, and even nations.

- Increasing temperature, drought, wildfire, and invasive species will accelerate transformation of the landscape.

- Under higher emissions scenarios, high-elevation forests in California, for example, are projected to decline by 60 to 90 percent before the end of the century.

- In California, two-thirds of the more than 5,500 native plant species are projected to experience range reductions up to 80 percent before the end of this century under projected warming.

- Projected changes in the timing and amount of river flow, particularly in winter and spring, is estimated to more than double the risk of Delta flooding events by mid-century, and result in an eight-fold increase before the end of the century.

- A steady reduction in winter chilling could have serious economic impacts on fruit and nut production in the region. California’s losses due to future climate change are estimated between zero and 40 percent for wine and table grapes, almonds, oranges, walnuts, and avocados, varying significantly by location.

By the way, Pielke’s critique does not directly address anything in this list, though his work does involve weather-related disasters, which would include floods. Asked by a commentator on his blog if he thinks the entire report should be dismissed based on the flawed interpretation of his research, Pielke replied: “I wouldn’t think so and would certainly hope not. At the same time the section which covers my research does not give me a lot of confidence in the process that led to the report.”

“The Australian Reality”

Australia's Simpson Desert. Photo: Mike Gillam

Australia's Simpson Desert. Photo: Mike Gillam

Referring to Australia’s seven-year drought, that’s how the state’s top water manager describes the new paradigm for water planning at the Dept. of Water Resources.

Speaking to a packed house at the annual forum of the Sacramento River Watershed Program yesterday, DWR Director Lester Snow said his staff is assuming that 2010 will be another dry year. Snow warned about “loss of resilience” in the state’s water system, calling it “completely unsustainable” in it’s present form, given predictions for population growth, coupled with anticipated effects of climate change.

All speakers at the forum seemed to agree that a paradigm shift is in order. Thomas Philps, a strategist at SoCal’s Metropolitan Water District, pointed out that in Victoria’s capital city of Melbourne (Australia), per capita water consumption runs about 40 gallons per day, while in California’s capital, it’s 280 gallons. As Sasha Khoka will report Monday morning on The California Report, Sacramento is just one of several cities in the Central Valley that still doesn’t meter its water use. Philps added that the Sacramento region is “on a trajectory” to use the same volume of water as Los Angeles, though he did not say by when.

UC Davis geologist Jeff Mount cautioned against relying on additional surface storage to secure California’s water future. Not only does storing water become “very expensive” year over year, but dams and reservoirs “don’t create any new water,” he said. (If some think Mount is taking a “jaundiced view” of the situation, it might be because he braved a bout of hepatitis to deliver his morning talk)

In a panel discussion on resource planning, moderator Greg Zlotnick of the Santa Clara Valley Water District asked panelists to respond with “true” or “false” to a quote from the Pacific Institute’s Peter Gleick in a story aired on NPR last week. The quote, as given by Zlotnick, was: “Government has built infrastructure and made promises that can’t be kept.” Here are the panelists’ responses:

Tina Swanson, The Bay Institute: “True.”

Philps: “True, but…” (Generally true but MWD doesn’t really expect to get its full contractual allocation of water anymore, anyway)

Don Glaser, US Bureau of Reclamation: “False, but…” (Water allotments from his agency’s Central Valley Project are intended to be “supplemental contracts,” to augment use of groundwater and other sources, but Glaser sees the statement becoming “more and more true in the future.”)

Snow: “Hell, no.”