What can the state do to better prepare for a drier future: groundwater management, water efficiency, water conservation … ?
In April, the UC Drought Science, Policy and Management Summit reached throughout the University of California system to bring together faculty and other experts to explore ideas and different approaches to mitigating the effects of the current drought while at the same time, preparing for future water shortages. In this panel, Steve Macaulay, consultant and former Deputy Director at DWR; Jay Famiglietti, professor of hydrology at UC Irvine; Ruth Langridge, researcher at UC Santa Cruz; Thomas Harter, professor of hydrology at UC Davis; Samuel Sandoval, assistant professor at UC Davis; and Kurt Shwabe, Assistant Professor at UC Riverside discuss what state policies are needed to prepare for future droughts.
Steve Macaulay: Retrospective, Resources, and Rewards
Consultant, Macaulay Water Resources, and former Deputy Director of DWR
Steve Macaulay began by recalling that it was the state’s first engineer, William Hammond Hall, who said in the 1870s who said that there is no limit that may be assigned to the amount of water which at sometime may come down the Sacramento Valley. “It seems like almost every decade, we set new records for both droughts and floods, and this is after his careful analysis of 20 years of measured hydrology in California,” he said, noting that his comments would address what the state has done in terms of policy responses in recent droughts.
In the 1976-77 drought, the State Board for the first time adopted emergency regulations to relax Delta salinity standards as there were no dry year standards in the water quality standards at that point, he said. “Ironically the only day it rained was the day of the emergency hearings in 1977,” he said. “The Department of Water Resources built temporary emergency barriers for the first time, and then the five-year old State Water Project had its first curtailments, something that was far beyond something the SWP ever envisioned in its full history.”
The drought in 1991 actually started in 1987, but through those early years, we were living off our stored water, both groundwater and surface water, he said. “1991 was a crisis, and a couple of key things happened,” he said. “Governor Wilson created an emergency drought water bank and opened that Pandora box of market based water transfers. DWR, having had experience in the 1977 droughts, built temporary barriers, and they worked well that year. And now the then-20 year old SWP had very severe curtailments. Initially it was 10% for urban, 0 for ag, but due to the ‘Miracle March,’ it rose to 30% urban, but remained at zero for agriculture.”
For the Drought Water Bank, DWR became the intermediary between the buyer and the seller, he said. “This really started with no prior institutional experience. You have all the economists in the world who say that market based transactions have a great appeal. It was a theory in January of 1991, and I worked at DWR at the time. We basically made it up on the fly, week by week.”
There were three methods of transfers: fallowing a crop, pumping groundwater and transferring surface water, or there were some reservoirs that had some water that they were willing to sell, he said.
“There were two unexpected consequences,” he said. “The first is that frankly, of the hundred of us who worked on the Drought Water Bank, none of us expected it to succeed, and it succeeded beyond our wildest dreams. It was extraordinary. People, after some initial hesitation, just kept coming to us all year long.”
“By the way, there’s no shortage of people who want to sell their neighbor’s water,” he added.
“The second thing is there were unintended third party impacts,” he said. “People who were neighbors of farms that sold their water – you can imagine what those impacts would be. And so it opened up a Pandora’s box.”
There were three drought water banks: 1991, 1992, and 1994, he said. “None of the ‘91 mistakes were repeated in 92. We made different mistakes in ‘92, which were not repeated in ‘94. We made another basic mistake in ‘94, which DWR still regretted, but you learn by experience. Again, we’d had no institutional experience up to that date.”
He then presented a slide showing estimated groundwater pumping for the last 90 years in the Sacramento Valley. “When people talk about overdrafting the Central Valley, they are largely talking about the San Joaquin Valley, but one thing that’s well known is that groundwater pumping in the Sacramento Valley to meet demands in the Sacramento Valley consistently has increased,” he said, noting that the black portions of the bars for the recent years represents the amount of additional pumping induced by market-based water transfers, which is small in comparison to the total amount. “The key thing I wanted to point out here is that the big spike in the middle, that’s 1977, that’s using the groundwater resources in the Sacramento Valley as they should be as our drought reserve, and then they go back to normal conditions,” he said, and noting the amount of groundwater pumping in recent years: “Well, the new normal is greater than 1977.”
Mr. Macaulay said his three Rs were ‘Retrospective, Resources, and Rewards’:
- Restrospective: We need to learn from past drought experiences, including how well our drought plans actually work, he said. We need to continue to work to improve water transfers, and we should examine how well the urban water management plans and water shortage contingency plans measured up to the 2014 drought conditions. We need to analyze the risks, particularly in the context of hardening demands, and then we need to examine if our agencies and laws were up to the task.
- Resources: We have to have resources in place to respond to droughts, including effective policies and regulations for water transfers, improved water shortage contingency plans, and updated risk analyses. “I want to reinforce what might my then teenagers about 20 years ago continue to tell me: ‘just deal with it.’ Drought happens in CA, drought happens all over the west; we should not be surprised that it shows up every few years.”
- Rewards: Particularly as the legislature contemplates major groundwater legislation in 2014, what kind of rewards might be in place to encourage people to do the right thing? “I’ll use the Sacramento Valley as an example. There are 35 groundwater management plans in the Sacramento Valley, and most of them are pretty good. … but there’s nothing that binds them all together. Thirty-five plans covering about three-quarters of the land covering the aquifers in the rich Sacramento Valley … There’s nothing that forces them together and there’s nothing that gives them the institutional tools.”
“If it’s broken, fix it, if it’s fixed, reward … what can we do to encourage people to do what we think is the right thing, including embracing risk,” Mr. Macaulay concluded.
Jay Famiglietti: Groundwater trends show need for better groundwater policies
Professor of Hydrology at UC Irvine
Professor Jay Famiglietti began by saying he works with a satellite mission called Gravity Recovery And Climate Experiment, or GRACE, that was launched in 2002. “The easiest way to describe it is that it works like a scale in the sky,” he said. “It responds to small changes in earth’s gravity fields that are triggered by the mass movements of water so we can literally weigh the regions around the world or around the country or around the state that are gaining or losing water.”
He then presented a slide with some of the results. “This is a map of the U.S. that we published last year that show the trends of water storage over the last decade or so,” he said, noting that the blue areas are gaining water and the red areas are losing water. “You see a couple of things. The northern half of the country is getting wetter and the southern half of the country is getting drier. We have some very distinct hot spots including the Central Valley and the southern high plains, and the southeast is far worse than people have really expected.”
He then presented a slide of total water storage changes as detected by the GRACE mission from 2002 to 2013. “When we take the GRACE data and we look at the Sacramento-San Joaquin River basins together, the chart on the right shows the monthly ups and downs of total water storage – soil moisture, snow, surface water and groundwater together.” He noted that there has been a big drop over the last few years. “It’s about 12.5 cubic kilometers per year, which is more water than all Californians use for domestic and municipal supply each year,” he said. “When we look at these data, it may be that this drought is not just a two year drought, but arguably we could say it’s been going on since 2006 and maybe we’re in a long term decline. The reason that we see this slightly different picture is that we’re looking at all the water, including the groundwater. Groundwater has more memory to it so it responds more slowly. We typically leave that out of our drought estimates and things like the US drought monitor.”
So how much of that is groundwater? “Focus on the black line,” he said, presenting another slide plotting surface water allocations against groundwater use. “One of the things we work hard on is taking the total water storage signal and then getting data on the snow, the surface water, soil moisture, and determining what the groundwater looks like,” he said. “These are the groundwater ups and downs, the monthly groundwater storage changes in all of the Central Valley. … The red bars and blue bars are the allocations of the State Water Project and the Central Valley Project, and so it’s pretty clear that when the surface water allocations go up, the groundwater recovers. When the surface water allocations go down, the farmers have to hit the groundwater pretty hard, and the groundwater goes into big decline. It’s almost a 1 to 1 match, and so the big issue for policy is can we keep going like this because the drought is worse than ever and allocations are at 0 and 5%.”
He then presented another slide showing cumulative groundwater depletion from the Central Valley from 1962 up to the present, combining USGS data in red and GRACE data shown in green. “What we see is our history of groundwater use over the last 50 years. A little bit of an increase in the wet period, and a big decline during the drought, a little bit of an increase, and then a big decline and so on … So where are we going from here?”
“I think that we’re poised for a huge run on the groundwater,” said Professor Famiglietti. “We know that the number of well permits has doubled and tripled in some counties, so it’s time for us to start thinking about the policy implications of groundwater management. There are things that people are talking about that include thresholds, monitoring and assessment, local management, maybe a statewide or a national backup, oversight, and enforcement. This is the way that I believe we have to go or we will run out of groundwater.”
Ruth Langridge: Groundwater reserves would reduce drought vulnerability
Researcher, Center for Global, International and Regional Studies, UC Santa Cruz
“The time to plan for drought is when it’s raining, and it seems very fortuitous that it is raining today,” began Ruth Langridge. “We started our project a number of years ago during a wet season, and I think people were wondering why we were even thinking about drought at that point in time, but in fact if you look at it historically, California experiences periodic droughts.”
“The standard thing to do when there’s a drought in our state is to pump more groundwater, and that increases during drought periods,” she said, presenting a slide showing the number of well permits issued in the Central Valley, and noting that it has increased as well this year. “Earlier studies in the 1987-1992 drought show a very similar pattern.”
“The problem is that the volume pumped during drought in many instances is not exceeded with replenishment during wet periods and the result has been a long term decline in groundwater levels,” said Ms. Langridge. “This is in part because we don’t get the replenishment from rain but also the fact that we don’t tend to think about reserving water during wet periods or in some way, maximizing our storage.” She noted that in the Pajaro Valley on the Central Coast, water levels fell significantly during the 87-92 drought and did not sufficiently recover afterward.
“Going back to the turn of the 20th century, we see the beginning of groundwater overdraft,” she said. “In fact, the Central Valley Project was in part constructed to help alleviate that groundwater overdraft, and for a little while, groundwater levels did in fact recover, but then you started to continually see declines again, and often during the dry periods, many of these basins are still in trouble.”
“We have developed a project that’s looking at the idea of developing local groundwater drought reserves,” she said. “This as a little different than the groundwater banking that’s going on in the Central Valley because we focus on both the Central Coast and the North Coast in the areas that are not receiving water from the big projects and that are very reliant to a large extent on local sources. Some of these communities are 100% groundwater dependent.”
They would be locally sourced, sited, and used, and would serve as a buffer during drought, she said. “They are less energy intensive, support groundwater dependent ecosystems, and most important, the goal would be to eventually recover groundwater levels and think about planning ahead for a drought.”
Ms. Langridge said the project is pretty elaborate and interdisciplinary, and is looking at legal, social, economic, and hydrologic aspects of trying to develop these drought reserves.
She has three specific policies to help encourage this approach:
- Incorporate drought protection into determinations of safe and sustainable yield. To a large extent, this isn’t necessarily done, she said. Safe yields don’t always account for the additional pumping that oftentimes occurs during a drought.
- When state funding is provided, whether it’s through IRWM or groundwater management plans, there should be a requirement to very specifically develop and implement groundwater improvements in management and ways to reduce overdraft, and to at least consider the development of groundwater reserves.
- Develop state-local cooperative partnerships or structures to consider how to develop sustainable groundwater withdrawals.
Thomas Harter: Groundwater legislation
Professor of Hydrology, UC Davis
Thomas Harter began by clarifying that one cubic kilometer is about 1 million acre-feet, give or take. “So summarizing what we just heard with a slightly different perspective, if you look at the numbers from 1960-2010, the average overdraft on an annual basis in the groundwater basins is on the order of about 2 million acre-feet per year,” he said. “But in drought years like 1989 through 1992, we’ve seen 40 MAF taken out of groundwater storage over the course of four years. We are looking at 10 MAF taken out that at some point we’re going to have to put back in if we want to be sustainable.”
He then gave some basic statistics. “We heard earlier that the combined urban and agricultural water use per year is on the order of 40 million acre-feet with 8 million going to urban areas and 32 million going to agriculture,” he said. “I wouldn’t call it normal; I would call it an average. Groundwater, out of those 40 MAF, groundwater accounts anywhere from 12 MAF and 20 MAF depending on how dry it is. That is the DWR estimate for the past. I would dare to say that this year, being an exceptionally dry year, that this year we will see well in excess of 20 MAF of groundwater being withdrawn from our aquifers statewide. And if you consider that 15 million would be average and perhaps sustainable, than in these exceptionally dry years, we’re coming back to this number of 5 to 10 MAF in excess of what we have in average year for recharge being withdrawn from our groundwater storage. So that’s one number, 5 to 10 MAF per year.”
He said that the Central Valley has groundwater storage of about 1000 million acre-feet, but that number doesn’t tell us much because to withdraw that much water out of the Central Valley aquifer would have huge implications, he said. “We have taken out about 100 MAF and that has created a storage capacity that indeed and in fact we can use and perhaps we can expand on that storage,” he said. “The point is that clearly we are limited in the amount of groundwater supply that we have and we cannot live we have lived for the last 40 years, and if this year is going to be part of the norm, part of the future, clearly we will have to change how we manage groundwater.”
“You have heard that California is the only state that hasn’t figured out how to manage its groundwater, he said. “I don’t think that’s a correct statement. It may be the only state that doesn’t have a state groundwater management plan, but in fact, it’s not, by any measure, the worst state in terms of how it manages groundwater. Texas may have a state groundwater management plan, but that management only says you cannot deplete your aquifer system in less than 50 years. It doesn’t say it has to be sustainable.”
“Drought years have been an enormous boost to how we manage groundwater,” he said. “What we will see in this year is a fairly comprehensive attempt at making another push toward better groundwater management. We introduced groundwater management plans in the 1992 drought, we’ve mandated that groundwater management plans be in place in the 2002 drought, and this drought, we’ll likely see legislation from the Governor.”
There’s a surprising amount of agreement on what needs to be done, he said. “I think in the state, large water groups, including ACWA, all agree on the fact that we have to do sustainable groundwater management and it cannot be what Texas does, which is a 50 year depletion horizon,” he said. “If we think the surface water permit system in the state to be dysfunctional, that should be a deterrence to have the same system implemented for groundwater.”
“There is a large consensus that management is going to be done regionally or locally. But what we will hopefully see this year are very clear mandates to local agencies and regional agencies in terms of what they are allowed to do and a very clear mandate to allow them to collect the data on water usage that they need to have and to have the authority to stop pumpers from pumping”, he said. “That is a very critical piece that we’re currently missing. We cannot get around putting that backstop in place.”
Mr. Harter said that managing groundwater can only be done by managing surface water. “We have to look at water supplies, groundwater management, and groundwater banking all at the same time, but we also have to consider groundwater quality when we look at groundwater quantity. The two cannot be separated. As part of this integration, a critical piece is going to be to link water management, especially groundwater management, to land use decisions. I hope we see legislation this year.”
Samuel Sandoval Solis: Efficient water use in California
Assistant Professor, UC Davis
“Efficient use of water is not a silver bullet,” began Samuel Sandoval Solis. “We always think about how efficiency is what will get us out of this trouble, and that is not true. It is part but it’s not everything. It has some unintended consequences. It may reduce the recharge to groundwater.”
“Despite the popular belief, there is still some room for improvement in irrigation efficiency and efficient use of water, but there is not much room there, and policies that consider efficient use of water should be coupled with other policies,” he said.
“I want to talk about is efficient use of water,” he said, presenting a slide with a chart showing the costs of different water management strategies drawn from data compiled from a recent PPIC study, and a chart showing the trends in types of irrigation used. “The trend has been less and less surface irrigation, and an increase in micro and drip irrigation while sprinkler irrigation systems have been pretty much consistent, and subsurface has been stable,” he said. “Growers are changing because they can get a higher crop yield and more money,” he said. “The other thing is that it is to avoid regulations. Some of the regulations to get water permit, they prefer to invest. This makes these fields more vulnerable economically, so they invest more. They have all this property that it has a high value, they are putting more value and then in these times they don’t’ have water, they have a larger investment.”
He then presented a slide comparing irrigation efficiency across the state in 2001 and in 2010. He said the data came from a census where they sent a form to growers who responded with their acreage, crops, and irrigation systems they use. “Overall, there is a 3% increase in how this system has changed in order to have more efficient use of water. … but there are the unintended consequences. Some of these are reduction in groundwater recharge and oftentimes more energy use, said Mr. Solis.
“My point is here that there the state used to put a lot of these goals in efficient use of water and water use efficiency, but they are not tied to other policies that can counteract some of these unintended consequences,” he said. “The reality of managing irrigation systems is very difficult. It requires good engineering and good practices.”
Kurt Schwabe: Water conservation: Untapped opportunities and uninformed approaches
Associate Professor of Environmental Economics and Policy, UC Riverside
Kurt Schwabe began by saying he would draw upon two themes from a recent book that he co-edited, Drought in Arid and Semi-Arid Environments, A Multi-Disciplinary and Cross-Country Perspective. “This is a book whose chapters were written by agronomists, ecologists, economists, hydrologists, irrigation specialists, water managers and policy makers from the U.S., Spain, Mexico, South Africa and Australia,” he said. “My first lesson is that if that if you really want to identify cost-effective and practical policy solutions to drought, you have to have a multi-disciplinary team of researchers focusing on it, with stakeholder and policy makers working in concert with you.”
“My second lesson that came out of this book is that I believe there are significant opportunities for policy to address drought more cost effectively if you do take a more portfolio approach to management,” he said. “Conversely, if you limit or narrow your choice set, you’re going to end up with more costly policies that are less productive.”
The book catalogs the portfolio of options into three general categories: supply augmentation, demand management, and institutional reform.
- Supply augmentation: These represent options that modify the impact of the meteorological event and the availability of the water supply. “Increase storage capacity, either surface water or groundwater storage capacity; increase conveyance flexibility, increase the opportunities for desal in very limited cases, perhaps, but more so in the reuse of treated wastewater or indirect potable reuse – those would be all ways to augment supplies,” he said.
- Demand management: “We explored options to reduce one’s exposure and vulnerability to drought through demand side management, and adaptation and mitigation, including improvements to use water use efficiencies on farm and increased water use efficiencies in urban settings using both price and non-price instruments. Significant research opportunities exist for better understanding of crop stressing, improving crop productivity, and on the cost effectiveness of different residential rebate, pricing, and social norms and social media programs.”
- Institutional reform: These include strategies that increase the ability of agents, sectors, and regions to respond and mitigate drought through institutional changes, as streamlining approval processes for temporary water transfers and increasing opportunities for growers and municipalities to partake in more water trading or groundwater banks. “I think we should consider developing options and future markets for water to reduce the exposure farmers have on the spot markets, and to further develop systems that can provide more up to date and accurate information on the state and trends of our natural, built, and economic systems.”
During the discussion period, Kurt Schwabe asks panelists if there is a way to use the groundwater storage capacity to capture some of the larger precipitation events that could potentially occur with climate change.
Steve Macaulay said that when he was working for DWR and studying the Kern Water Bank, “What we found out through that was that water goes into the ground slowly and it comes out slowly, and so you have to use groundwater storage conjunctively. You have to operate the surface water and groundwater systems together and so the quickest way of putting water in the ground is what they call in-lieu recharge, or delivering water in wet years to farmers who would otherwise pump and get them to turn off their water, but a lot of careful thought needs to go into this.”
Ruth Langridge said that there is an interesting collaborative project along the coast between Santa Cruz and the Soquel Creek Water District that shows how smaller water districts could work cooperatively. “The idea is that Soquel Creek is completely groundwater dependent, and they are quite concerned that they have upcoming salt water intrusion. Santa Cruz is almost entirely reliant on surface water, so they are really in trouble during the dry years, in fact, they are very worried right now. So the idea would be, either through a small desal plant or by capturing some of the runoff from the San Lorenzo River if we’re going to be having increased runoff, and the idea would be to send that water over the Soquel Creek during wet years in lieu of them pumping their groundwater which then becomes the equivalent of their storage during dry years, and then during dry years, Santa Cruz would either rely on the desalinated water or they will rely on having filled up their reservoirs.”
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