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.
California Storms: A Dent in the Drought
Spillway at Alpine Lake on Mt. Tamalpais. File photo: Marin Municipal Water District
A version of this post also appears on Dan Brekke's personal blog, Infospigot. Also see our updated map of reservoir conditions at the end of this post.
By Dan Brekke
Is California's drought over? OK, let's take a step back. Yes, I realize one could debate whether the last three years in California actually constitute a drought. But that's a discussion for another time. For now, I think everyone can agree that we've had lower-than-average precipitation for the past three years.
The only reason to ask the question is that, after the first half of the wet season delivered only spotty rain, we've had a pretty solid week of downpours. Water is sluicing into our reservoirs, and the hills are greening up. Some counties, like Marin, have water tumbling down the spillways. All of that is a sign of what we think winter should be here.
My favorite water statistic from last week: when the storms were at their heaviest around Lake Shasta, California's biggest reservoir, water was flowing into the lake at about 500,000 gallons per second. That's 1.5 acre feet, or about enough for two-to-three "average" households for a year, every second.*
Amazing numbers like that aside, the people who get paid to think about whether the drought is over say "not yet." Last week, Quest managing editor Paul Rogers wrote a good summary of the situation, for The San Jose Mercury News.
Rogers' story does contain one bit of quirky California thinking about rain and water, though. He quotes a well established local meteorologist, Jan Null, about where we stand in terms of normal rainfall, saying: "This is a great start, but we need to keep it going."
Of course, Null recognizes better than most that the amount of rain we get and when we get it is out of anyone's control. But once you understand the importance of water in California, once you get how crucial the winter rains are, there's a score-keeping aspect to weather-watching here. It becomes second nature to study the rain gauge and the seasonal precipitation table as an index of performance, a reflection on whether a great collective goal is being attained. Lots of rain means we're doing well (and that we can put the complexities of water supply out of our minds). A dry spell means we're failing (and the prospect of hell to pay, or at least the strong possibility of stringent conservation measures).
But in reality, there's no performance going on. The rain is the rain, and the climate is the climate. California's rainfall is famously variable. Dry spells can be counted on and the current run of dry years is the third we've had since I arrived in Berkeley in the 1970s.
My first California winter, 1976-'77, was bone-dry and was in fact the second year of the driest two-year period ever recorded here. A decade later, from roughly 1986 through 1992, we had another run of dry years. And if our winter rains were to stop now, we'd be in the fourth year of drier-than-normal years. In between these periods we've had average years and very wet years and years that didn't quite hit the average. That might not be too different from anywhere else. The reason it's a bigger deal here than it might be in, say, Wisconsin, is that we have a six-month dry season. We need to store water to get through that. We have 37 million people and millions and millions acres of farmland that need water, whether it's falling from the sky or not. Thus the need to believe we can wish the rain to keep going during the wet season and the tendency to feel disappointment when the winter turns into a string of dry, sunny days.
*500,000 gallons per second. Here's the arithmetic: California Department of Water Resources figures show that in the hour between noon and 1 p.m. on Tuesday, January 19, net inflow into the lake was 66,288 cubic feet per second. That's the highest inflow figure for any single hour that week. One cubic foot equals 7.48 gallons. 66,288*7.48 = 495,834.24 gallons. One acre-foot = 325,851 gallons. And 495,834.24/325,851 = 1.52 acre-feet. Per second. For the entire 24 hours of the 19th, Lake Shasta's inflow averaged just over 1 acre-foot a second.
View KQED: California Reservoir Watch in a larger map
Western Lakes Warming Up Rapidly
Lake Tahoe from above Emerald Bay. Photo: Craig Miller
Some lakes in Northern California and Nevada are warming twice as fast as the surrounding air temperature, raising concerns that climate change may be affecting aquatic ecosystems more rapidly than terrestrial ones, according to a recently published study.
Researchers from the Tahoe Environmental Research Center, UC Davis and NASA's Jet Propulsion Laboratory in Pasadena, studied Lake Tahoe, Lake Almanor, Clear Lake, and Mono Lake in California, and Nevada's Pyramid and Walker Lakes, by analyzing 18 years of temperature data from satellite sensors.
Long-established instrument buoys provided a flow of temperature data for Tahoe, dating back to 1968, which allowed the team to calibrate satellite readings, raising confidence in data gathered from the other lakes. Previous studies have documented the warming of Lake Tahoe but John Reuter, associate director of the Tahoe Environmental Research Center (TERC), says the new study takes that information one step further.
"This study really shows that this phenomenon is happening on a much larger scale than just Lake Tahoe," said Reuter.
All of the lakes studied showed a strong warming trend among summer nighttime temperatures between 1992 and 2008. The two lakes that warmed the most during that time, Almanor and Mono, warmed 4.3 degrees (F). During that time Lake Tahoe's surface waters warmed 3.7 degrees, averaging .23 degrees annually. In contrast, Tahoe City's air temperature increased just .1 degree each year.
TERC director Geoffrey Schladow, who co-authored the study, said there is no doubt in his mind that rising lake temperatures are related to climate change, and he expects that it's happening across the world, not just in Northern California and Nevada.
"The significance of this study is that across the western United States these very different lakes are displaying signs of warming. It's not just a Tahoe issue, it's a regional issue. And in all likelihood, it's a global issue,"said Schladow.
Over the next six months, researchers will be using the remote sensors to extend the study to 50 lakes across the world to evaluate whether or not large lakes everywhere are warming at similar rates.
Warmer temperatures can affect water circulation, which influences the amount of oxygen and nutrients available throughout the lake. A 2008 study from TERC predicts that warming due to climate change could dramatically affect the amount of mixing in Lake Tahoe, which would deplete the bottom water of oxygen and drastically disrupt the food web.
"Temperature is one of the conditions that dictates who lives in the lakes," said Schladow. "Warmer temperatures may make the lakes more hospitable to invasive species and put native species under stress. I'm not saying this is happening yet, but it could."
In his article about the study, Matt Weiser of the Sacramento Bee has some examples of how warmer temperatures can affect lake ecosystems. And KQED news editor Dan Brekke has assembled an interactive map (below), showing the locations and some temperature data for lakes in the study.
View California's Warming Lakes 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
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%.
California Losing Groundwater Rapidly
Nearly lost amid the three-ring circus of Copenhagen coverage is the annual gathering in San Francisco of the American Geophysical Union. We're doing our best to staff selected sessions there. Climate Watch contributor Lauren Sommer was there for some grim new research on groundwater in the Central Valley.
California's Central Valley has lost nearly enough water in the past six years to fill Lake Mead, according to NASA scientists presenting at the American Geophysical Union Conference in San Francisco this week. Nearly two-thirds of that loss–20.3 cubic kilometers of water–is from groundwater depletion.
With the recent drought, groundwater has been an important water source for California's Central Valley agriculture, but getting a picture of that water use hasn't been easy. Water districts haven't been required to report groundwater pumping in their areas. That's something the recent Delta overhaul package of legislation now requires, but according to Jay Famiglietti of UC Irvine, the records to date aren't very complete. Wells are sparse and the measurements have been sporadic.
The majority of the water loss since 2003 has been focused in the San Joaquin Basin at the southern end of the Central Valley, which is losing 3.5 cubic kilometers of water each year. The bulk of that loss is the result of groundwater depletion.
Famiglietti says this is due to a "triple threat" in California. First came the drought, then decreased water allocation and more groundwater pumping. Finally, with less surface water, the groundwater aquifers have a reduced opportunity to recharge. Famiglietti says it's clear that California is using groundwater at an unsustainable rate, which "poses significant threats to food production in US and the California economy."
Groundwater basins in the Central Valley. Image: NASA
This large-scale picture of California's groundwater comes from NASA's Grace project. Twin satellites orbiting the Earth detect changes in the gravitational field, caused by the movement of water. Those satellite measurements act like a“scale at the bottom of the ocean weighing how much water is in each of these spots," according to NASA's Michael Watkins. They also detect changes in snow, surface water and soil moisture.
The Grace project, though, is becoming a "senior citizen," according to Watkins and is reaching the end of its technological life. He says quality of their water research, which has included other spots around the globe, speaks to the need for another generation of the project. Famiglietti says, though this data can't replace ground measurements, he hopes it will be taken into account by state agencies faced with making the tough choices about California's aquifers.
Everything You Know (About Water) is Wrong
If Dan Brekke isn't editing newscasts at KQED Radio, chances are that he's poring over charts full of arcane statistics from the state Department of Water Resources. Call it a hobby. Okay, call it an obsession. Either way, we frequently turn to Dan for his insights into California's water conundrum.
Flooded rice fields in the Sacramento Valley. Photo: Craig Miller
Everything You Know is Wrong
By Dan Brekke
California is home to 37 million people—and to 37 million water experts. If no one’s ever said that, someone should have.
There’s nothing more central to life here and no subject that excites stronger opinions. Recent events have shown that those opinions can easily harden into certainty about what needs to be done to solve all of California’s water problems—the needs of those 37 million people, the needs of the state’s incomparably rich agricultural industry, the needs of native fish and ecosystems.
We’ve long since learned that one person’s "solution"—to build dams and divert water for farms and cities, say—can be another’s nightmare—for instance, the communities that depend on healthy fisheries for their well-being. The conflicts over water are so deep and longstanding that they can make rational discussion difficult or impossible.
This week, though, the Public Policy Institute of California published a report that aims to inject some understanding into the water debate by challenging opinions and misconceptions. The report tests eight widely-held beliefs about water against the complex realities that underlie them. The first myth is fundamental to how we see water issues: “California is running out of water.” The reality the PPIC and its all-star panel of water experts propose is a sobering one: “California has run out of abundant water (our italics) and will need to adapt to increasing water scarcity.”
There’s something in the list of myths to rankle just about everyone. One myth goes like this: “[Insert villain here] is responsible for California’s water problems.” The report goes on to assess several villain-candidates, including:
- Wasteful Southern California homeowners with their lush lawns and luxurious swimming pools,
- Farmers who get federally subsidized (read “cheap”) water, and
- Protections for endangered species (as in "Why are we giving water to that Delta smelt?”).
In reality, the report says, coastal Southern California does an excellent job of limiting residential water use; farmers getting cheap water are in fact paying a price for the subsidy and are becoming more efficient water users; and actions taken to protect the smelt has had a comparatively small impact on water shipments through the Delta.
The PPIC says in the introduction to “California Water Myths” that a “policy based on facts and science is essential if California is to meet the multiple, sometimes competing goals for sustainable management” of water for the rest of the century. No one can argue with that, though it’s certain that squabbles over water will persist. Maybe the best we as Californians can hope for is an honest effort to try to understand the needs of all other water users, and to give each of them the benefit of the doubt when considering solutions to our water problems.
The PPIC report: “California Water Myths," is available on the institute website or in an excellent interactive version put together by the UC Davis Center for Watershed Sciences.
Meanwhile, how are we doing this winter? Not great. Below is an interactive map of California's major reservoirs, comparing their current levels to average or "normal" levels for this time of year.
View KQED: California Reservoir Watch in a larger map
State Water Deliveries May Set New Low
State water officials have announced they are likely to release a record-low allocation of water to cities and farms next year– just five percent of what water contractors have requested. Though still preliminary, it’s the lowest allocation since the State Water Project began delivering water back in 1967.
The announcement may have caught some by surprise, since Department of Water Resources (DWR) data would seem to show reservoirs at higher levels than last year at this time, with major reservoirs at 69% of storage capacity, compared to 57% last year.
When I asked DWR Deputy Director Susan Simms about it, even she was stumped at first. But then she called me back to say that the data includes both federal and state reservoirs, and the state’s storage levels at both Lake Oroville and San Luis Reservoir (shared with the feds) is actually lower than last year (52% and 48% of "normal," respectively). And, she says, the state has to contend with pumping restrictions to protect both salmon and delta smelt this time around.
DWR Director Lester Snow told reporters this morning that there's nothing in the recently passed bundle of state water bills that can provide any immediate relief. And if you thought the prospect of increased precipitation from El Nino could save the day, don’t get out the umbrella just yet. David Rizzardo, Chief of the state’s Snow Survey section, estimates there’s only a 50-60% chance of a stronger El Nino kicking in this year. December and January will be the most telling months–but precipitation from El Nino would likely be concentrated in the southern half of the state. Officials say that would provide more "flexibility" in meeting water needs systemwide, but all of California's biggest reservoirs are located in the northern part of the state.
December water delivery estimates almost always get a boost once it starts snowing. Last year's initial projection was 15%, and that was later revised upward, eventually to 40 percent. Snow called today’s estimate “very conservative.”
If you think the five percent figure is supposed to scare us, it is. Water officials want to send a message that Californians need to be prepared to conserve. The state’s drought coordinator, Wendy Martin, just returned from a water tour in Australia, where she says she saw water-saving measures in place that California has yet to fully develop: storm water recapture, water recycling, and more. Martin also observed that the Australians now wish that they'd taken the epic drought of the last several years more seriously, sooner.
$11 Billion in Water Bonds: Follow the Money
Governor Schwarzenegger traveled to Fresno County Monday to sign the centerpiece of last week’s package of water bills—an $11.14 billion bond measure that would pay for new dams and reservoirs and a sweeping program of conservation, water recycling and drought relief projects.
The governor appeared at a Friant Dam press conference with state Senator Dave Cogdill, R-Modesto, author of the bond initiative. Schwarzenegger said he’s hopeful that the bond, along with other measures in last week’s comprehensive water agreement, will put an end to the “holy water wars” pitting Northern v. Southern California and among cities, agriculture, fishing communities, and environmentalists.
The the governor signed the bond bill amid criticism that last-minute negotiations added more than $1 billion in earmarks designed to win support for the measure.
See our map, prepared by KQED editor Dan Brekke, for a detailed breakdown of where the $11.14 billion in bond money is supposed to go.
View Where Would the Money Go? in a larger map
View Where Would the Money Go? in a larger map
When Will Lake Mead Go Dry?
Exposed turbine intakes and the "bathtub ring" at Lake Mead. Photo: Craig Miller
You can see a slide show of the retreating waters at Lake Mead and Hoover Dam and listen to my radio feature from The California Report. Also, The American Experience will rerun its documentary on Hoover Dam, Monday night on most PBS stations.
The Las Vegas Sun has a digital clock on its website, counting down to a theoretical doomsday when the city's principal source of water would go dry. Wagering on that question may not have found its way into the sports books on the Strip–but it did become a lively pastime among engineers and hydrologists, when a report emerged from San Diego's Scripps Institution, with a dire forecast. The paper, by climate physicist Tim Barnett, put the odds at 50-50 that Lake Mead, the giant reservoir behind Hoover Dam, would reach "dead pool" by 2017. That's the point at which the dam shuts down and neither hydroelectric power nor water emerges from it.
The Barnett study "definitely raised eyebrows throughout the basin," admits Terry Fulp, deputy director of the U.S. Bureau of Reclamation's Lower Colorado Region, which operates Hoover Dam and Lake Mead. As it turns out, Barnett was a bit pessimistic. Subsequent work by him and others revealed that he overestimated the evaporation rate at Lake Mead, and omitted inflows below a certain point on the river.
The bottom line, according to Balaji Rajagopalan at the University of Colorado: Doomsday is not quite that near at hand. But that doesn't mean it's not on the horizon. "After 2027, the demand increase outpaces the supply decrease," Rajagopalan told me in a recent interview. "And that’s why much of the risk explodes from 2027 to 2057."
All of these studies are couched in probabilities, much in the same way that the Corps of Engineers talks about a "100-year" flood. Rajagopalan says: "Even in our study, we have a 50% risk [of dead pool], but that occurs in 2057. And that makes a big difference in terms of water managers, what they can do."
One of those managers is Pat Mulroy, who directs the Southern Nevada Water Authority. Her constituents rely on Lake Mead for 90% of their water, so she says she's not inclined to wait around for a consensus. "I mean, during the entire period of the ‘90s when we were bickering with our friends in the lower basin over surpluses, there was zero probability that the drought that we’re currently in was going to happen," Mulroy told me. "I’ve lost confidence in probabilities."
The Bureau's Fulp says the Colorado system leans heavily on the huge water storage capacity of Lake Mead and its sister reservoir upstream, Lake Powell. "We’ve known for decades that this system is highly variable and that’s why so much storage was built." When filled to capacity (which it was, more or less, 10 years ago), Lake Mead alone can hold enough to put an area the size of Pennsylvania under a foot of water. But a 10-year drought has left Mead at just over 40% of capacity (so think of flooding something more the size of Costa Rica). Just as current evidence and climate models both point toward lessening flows on the Colorado, many parts of the southwest still see relatively high population growth.
Scientists continue to run their statistical models aimed at handicapping the Colorado's demise as a dependable bringer of water. But as Fulp sums it up, "It’s really a debate about when. It’s not really 'if."
I regret an error of my own that appeared in the radio feature. I misstated the number of people in southern Nevada who are dependent on water from the Colorado. The correct number is about two million.
USGS: Americans More Water-Conscious Overall
Lake Mead in October, 2009 Photo: Craig Miller
Despite the addition of 81 million people over the period, Americans were using less water in 2005 than they were in 1975, according to the latest numbers released from the USGS.
The per-capita decrease of 30% since 2000, down to 1383 gallons per person per day, is a level not seen since the 1950s. Of course this doesn't mean that each person in the United States is using more than a thousand gallons per day at home–that number is somewhere between 54 (if you live in Maine) and 190 (if you live in Nevada). The USGS number is derived from dividing total water withdrawals by total population. In 2005, the total withdrawal was 410 billion gallons per day (5% less than in the peak year, 1980) and the total population was approximately 310 million.
An analysis by the Oakland-based Pacific Institute finds that the changes in national water use are due to improvements in efficiency, particularly in industrial use and irrigation. However, the largest category of water use–that used for producing energy–is growing (by 3% between 2000 and 2005), and the analysis cites this as a worrying trend as the population increases, particularly in dry parts of the country. In 2005, 49% of all water withdrawals were for cooling power plants.
"Far more water is required for nuclear and fossil fuel energy systems than for most renewable energy systems," said Peter Gleick, president of the Pacific Institute, in a statement about the new numbers. "Water availability will increasingly limit our energy choices as climate change accelerates and population continues to grow." California's two commercial nuclear plants are located on the coast and use sea water for cooling.
More efficient farming seems to be one of the bright spots in the report. Irrigation withdrawals in 2005 declined to the 1970 level of 1.28 billion gallons per day, even though the amount of irrigated land in the nation has increased by millions of acres since 1970. It seems that American agriculture is, in fact, doing more with less, thanks to more efficient sprinklers and drip irrigation systems. Even so, agriculture still claims about 77% of "developed" water in California, according to Ellen Hanak, water policy analyst with the Pubic Policy Institute of California.
The Pacific Institute commentary added some sobering notes:
The United States, although relatively water-rich, faces a range of threats to its vital supplies of freshwater. Overuse has turned the Colorado River into little more than a trickle. Overuse and contamination threaten the massive Ogallala aquifer, which runs from Texas to South Dakota and is an important source of irrigation and drinking water. Political and economic conflicts are growing between Alabama, Florida, and Georgia over water use. And other serious threats to our water resources – including climate change, environmental destruction, and population growth – remain unaddressed.
Household water use across the country is growing proportionately to U.S. population growth. While people are becoming more water-efficient at home, these behavioral changes are being balanced out by a shift in population to hotter, drier areas, such as the Southwest.
The Pacific Institute's Circle of Blue Water News has interactive maps showing which states have decreased their water withdrawals between 2000 and 2005 and total water withdrawals by state for this time period, as well as charts tracking U.S. water withdrawals since 1950.
11/18/09 Update:
Listen to audio of Peter Gleick discussing the report's findings on today's broadcast of NPR's Morning Edition.
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