PALO ALTO, Calif. (CN) – While this past winter busted California’s five-year drought, a new Stanford University study shows how the dry years did permanent damage to Central Valley aquifers. 
 
 A satellite remote-sensing study performed by Stanford researchers shows a portion of the Central Valley sank by as much as three feet due to overpumping of groundwater during the drought, permanently reducing the region’s capacity for water storage. 
 
 “California is getting all of this rain, but in the Central Valley, there has been a loss of space to store it,” said study co-author Rosemary Knight, a professor at Stanford’s School of Earth, Energy and Environmental Sciences. 
 
 The alteration of the clay layers that comprise the San Joaquin Valley translates into a permanent loss of natural storage capacity of anywhere between 360,000 to 600,000 acre-feet of water, the study says. 
 
 As a point of comparison, the Hetch Hetchy Reservoir – which provides water to San Francisco and is roughly the size of the Yosemite Valley – holds about 360,000 acre-feet of water. 
 
 While the study focuses on a drought that lasted from 2007 to 2010, the researchers say the results can be extrapolated to the most recent five-year drought that finally ended this year. 
 
 “I think it’s safe to say that the latest drought may have caused at least as much, or even more, subsidence and permanent compaction in the region than the last one,” said Ryan Smith, a doctoral candidate who co-authored the study along with Knight. 
 
 The water loss has ecological and economic consequences, as the agriculture in the San Joaquin Valley is a $17 billion industry that feeds much of the world. 
 
 Farmers have been forced to turn to groundwater as their allotments from the Central Valley Water Project shrank to as little as 5 percent of what they are entitled to last year. 
 
 The good news is that the U.S. Bureau of Reclamation recently announced farmers would get 100 percent of their allocation this year, after the Sierra – which supplies a good portion of the state’s water – saw the wettest year on record this winter. 
 
 The Northern Sierra’s 8-station index has so far seen a total of 90.2 inches of precipitation, beating the previous record of 88.5 inches set in 1982-83. 
 
 Gov. Jerry Brown officially declared an end to the drought emergency on April 7 and 
 
 The state’s Department of Water Resources took its critical April 1 snowpack measurement and found that it was 94 inches deep, one of the deepest ever recorded. The snowpack will continue to replenish reservoirs on both sides of the Sierra well into the summer months. 
 
 However, the permanent loss of storage in the Central Valley will make inevitable future droughts much harder for the region’s farmers to endure. It also makes it more difficult to extract groundwater in the present, according to the researchers. 
 
 “It’s like trying to suck water from a really thin straw,” Knight said. “The pressure that needs to be exerted to pull the water out gets greater and greater as the clay structure collapses.” 
 
 The researchers got their data using satellite technology called Interferometric Synthetic Aperture Radar, or InSAR, which is used to measure small-scale changes in elevation. 
 
 They say the technology is a good example of how such satellites can provide real-world applications to water supply and agriculture. 
 
 While compaction due to water loss in the clay layers is irreversible, the scientists say there are solutions to the problem. 
 
 They encourage farmers to stop pumping water from the clay layers and instead draw water from sandy or gravel layers of the earth, which are less susceptible to permanent compaction and are replenished more easily through rainfall. 
 
 While identifying sandy and gravel layers was previously possible only by drilling expensive wells, researchers are working on a method to permanently map the sediment layers of the Central Valley using a helicopter and electromagnetic tools. 
 
 Like this: Like Loading... ||||| Given the historic low temperatures and snowfalls that pummeled the eastern U.S. this winter, it might be easy to overlook how devastating California's winter was as well. 
 
 As our “wet” season draws to a close, it is clear that the paltry rain and snowfall have done almost nothing to alleviate epic drought conditions. January was the driest in California since record-keeping began in 1895. Groundwater and snowpack levels are at all-time lows. We're not just up a creek without a paddle in California, we're losing the creek too. 
 
 Data from NASA satellites show that the total amount of water stored in the Sacramento and San Joaquin river basins — that is, all of the snow, river and reservoir water, water in soils and groundwater combined — was 34 million acre-feet below normal in 2014. That loss is nearly 1.5 times the capacity of Lake Mead, America's largest reservoir. 
 
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 FOR THE RECORD: 
 
 Drought: In some March 13 editions, the byline on an Op-Ed article about water was James Famiglietti instead of Jay Famiglietti, as the author prefers. 
 
 A previous version of this article's headline left the impression that California has only one year of water left. As the article indicates, the state has one year of water stored in its reservoirs. 
 
 As I focus on California's relentless drought, I find I'm documenting the plight of the environment: The effects of the struggle between people and nature. I began my journey by exploring California's rivers, lakes, canals and reservoirs in search of visual effects of the drought. (Allen J. Schaben / Los Angeles Times) 
 
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 Statewide, we've been dropping more than 12 million acre-feet of total water yearly since 2011. Roughly two-thirds of these losses are attributable to groundwater pumping for agricultural irrigation in the Central Valley. Farmers have little choice but to pump more groundwater during droughts, especially when their surface water allocations have been slashed 80% to 100%. But these pumping rates are excessive and unsustainable. Wells are running dry. In some areas of the Central Valley, the land is sinking by one foot or more per year. 
 
 As difficult as it may be to face, the simple fact is that California is running out of water — and the problem started before our current drought. NASA data reveal that total water storage in California has been in steady decline since at least 2002, when satellite-based monitoring began, although groundwater depletion has been going on since the early 20th century. 
 
 Right now the state has only about one year of water supply left in its reservoirs, and our strategic backup supply, groundwater, is rapidly disappearing. California has no contingency plan for a persistent drought like this one (let alone a 20-plus-year mega-drought), except, apparently, staying in emergency mode and praying for rain. 
 
 In short, we have no paddle to navigate this crisis. 
 
 Several steps need be taken right now. First, immediate mandatory water rationing should be authorized across all of the state's water sectors, from domestic and municipal through agricultural and industrial. The Metropolitan Water District of Southern California is already considering water rationing by the summer unless conditions improve. There is no need for the rest of the state to hesitate. The public is ready. A recent Field Poll showed that 94% of Californians surveyed believe that the drought is serious, and that one-third support mandatory rationing. 
 
 Second, the implementation of the Sustainable Groundwater Management Act of 2014 should be accelerated. The law requires the formation of numerous, regional groundwater sustainability agencies by 2017. Then each agency must adopt a plan by 2022 and “achieve sustainability” 20 years after that. At that pace, it will be nearly 30 years before we even know what is working. By then, there may be no groundwater left to sustain. 
 
 Third, the state needs a task force of thought leaders that starts, right now, brainstorming to lay the groundwork for long-term water management strategies. Although several state task forces have been formed in response to the drought, none is focused on solving the long-term needs of a drought-prone, perennially water-stressed California. 
 
 Our state's water management is complex, but the technology and expertise exist to handle this harrowing future. It will require major changes in policy and infrastructure that could take decades to identify and act upon. Today, not tomorrow, is the time to begin. 
 
 Finally, the public must take ownership of this issue. This crisis belongs to all of us — not just to a handful of decision-makers. Water is our most important, commonly owned resource, but the public remains detached from discussions and decisions. 
 
 This process works just fine when water is in abundance. In times of crisis, however, we must demand that planning for California's water security be an honest, transparent and forward-looking process. Most important, we must make sure that there is in fact a plan. 
 
 Call me old-fashioned, but I'd like to live in a state that has a paddle so that it might also still have a creek. 
 
 Jay Famiglietti is the senior water scientist at the NASA Jet Propulsion Laboratory/Caltech and a professor of Earth system science at UC Irvine. 
 
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– Even the biggest reservoir in the US wouldn't provide enough water to replace what's been lost in California's drought. In fact, you'd need 1.5 times that much water, or 11 trillion gallons, to do so, according to NASA satellite findings. Another way to put it in perspective: It's 130,000 Rose Bowls' worth of water, USA Today notes. It's also more water than California uses every year, even with 38 million residents. This is the first time the amount of water needed to end a drought has ever been calculated, NASA reports. The study involved two satellites tracking the planet's gravitational field; small changes in the field are associated with changes in the water supply, Mashable reports. Each year since 2011, the Sacramento and San Joaquin river basins have lost about 4 trillion gallons. What's more, the snowpack in the Sierra Nevada mountains is just half of what earlier estimates suggested, and it's "one of the three lowest on record and the worst since 1977, when California's population was half what it is now," a researcher says. That means less snow melt and more absorption of sunlight into the ground, helping warm the planet and leading to drier conditions that make it more difficult to get snow water to reservoirs, he adds. "It takes years to get into a drought of this severity, and it will likely take many more big storms, and years, to crawl out of it," says the water study's leader.