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UCI Podcast: How drought and climate change threaten California’s water

Better management of groundwater could help, says Nicola Ulibarri

March 30, 2021
UCI Podcast: How drought and climate change threaten California’s water
In this episode of the UCI Podcast, Nicola Ulibarri, an assistant professor of urban planning and public policy, discusses how droughts, floods and climate change shape California’s management of water resources. School of Social Ecology

Rain is scarce in much of California, and most of California’s people live in water-starved regions. And yet the state is, by some measures, the fifth largest economy in the world. How? Because during the last century, California has built a complex network of dams, pumps and canals to transport water from where it falls naturally to where people live.

But climate change threatens to upend the delicate system that keeps farm fields green and household taps flowing.

In this episode of the UCI Podcast, Nicola Ulibarri, an assistant professor of urban planning and public policy who is an expert on water resource management, discusses how droughts and floods have shaped California’s approach to water, what policy changes resulted from the record-breaking drought of 2011-16, and how better groundwater management might offer a solution for the future.

In this episode:

Nicola Ulibarri, assistant professor of urban planning and public policy

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Transcript

AARON ORLOWSKI, HOST

In California, drought is never far away. The state suffered some of its driest years on record from 2011 to 2016, and today the vast majority of California is currently experiencing drought conditions. These water challenges will only grow more severe as climate change worsens.

How have droughts and floods shaped California’s water system? And how can groundwater management help us weather climate change? 

From the University of California, Irvine, I’m Aaron Orlowski. And you’re listening to the UCI Podcast. Today, I’m speaking with Nicola Ulibarri, an assistant professor of urban planning and public policy at UCI.

Professor Ulibarri, thank you for joining me today on the UCI Podcast.

NICOLA ULIBARRI

Thank you very much for having me.

ORLOWSKI

So California is, by some measures, the fifth largest economy in the world. And for at least a century, a lot of our economic growth has been due to the way we manage and distribute water here in the state. So when you look at water resource management in California, statewide, how are we using our water? And where does it go?

ULIBARRI

Generally, when we talk about water use, we kind of put it in three big buckets. The first bucket is what we call environmental water. So this is water that stays in the environment, things in rivers and lakes. And here in California, about 50 percent of our total surface water in the state goes to environmental uses, especially up in the northern part of the state. The other two big buckets are the human use, so agriculture and urban water use. And in general about 40 percent of our water goes to agricultural production. And the other 10 percent goes to urban water uses. The exact percentages vary a lot based on whether it’s a wet or dry year — so in a really dry year, we see less water going to the environment — and also where in the state you are. So for instance, here in Southern California, the vast majority of our water goes to urban water uses. This is drinking water supply, industrial water uses, manufacturing, things like that, with only a fraction going to either agriculture or environmental uses.

ORLOWSKI

And then we also move water around a lot. So how much of it is going from north to south and other places in the state?

ULIBARRI

Basically the challenge here is that the place where people live — either Southern California or along the coast, like in the Bay Area — are not places where we have a lot of water naturally. So all of our big rivers and the larger precipitation all is in the northern part of the state or in the Sierra Nevadas. And so we move water a lot. So we have a couple of major infrastructure projects like the State Water Project, the Central Valley Project, the Colorado River Aqueduct, where we go and grab water and move it hundreds of miles away, for either agricultural water use or for urban water supply. For instance, here in Orange County, I know that a substantial amount, more than half of our water, is coming in from either the Colorado River or from the State Water Project, mostly from the Feather River way up north.

ORLOWSKI

So suffice it to say, this is not a natural system and it relies on a ton of engineering. So are there any particular events or projects in the history of California’s water that really stand out to you as pivotal moments where we as a state built something huge or an event happened that has contributed to our engineered system today?

ULIBARRI

There are a few key moments that I would point to. The first one is the California Gold Rush — 49ers, 1849 — that set up our water rights system, as we know it today. And basically this was because to really set up and do mining well, you needed to have a guaranteed source of water. But that water — where the gold was wasn’t necessarily always right along a river. And so the miners decided, well, if I’m going to bother building all this infrastructure to get the water from the river over to where I want to be sluicing for gold, that they needed — basically, they set up a first come,first served system. So if you were the first one to divert water from that river, you got what we call priority. If you’re the second person to come in, you get second priority. So on and so forth down the line. And that’s still the system that we use today. So the people who own the oldest water rights in a river get their full water usage allocated first. And then the more junior users sort of have to wait in line.

Second, and this was more of a psychological impact than anything else was, right when the state was getting set up, we had a few major flood events. So in January of 1850, California is a brand new state and there’s a major flood in Sacramento, and actually Governor Leland Stanford had to go to his inauguration on a boat. And then a few years later in 1861 and 1862, we had the largest flood in the historic record in California. So most of the Central Valley was underwater for several months. It rained for a month, basically 28 days straight, in Los Angeles. Here where we are in Orange County, we would have been sitting under about four feet of water. So it was a very pivotal moment, realizing just how variable water could be from year to year. So some years there’s lots of water, and some years there’s almost no water.

ORLOWSKI

That’s incredible. That must have had a tremendous effect on what state leaders did to try and manage too much — or maybe if they were starting to realize — too little water depending on the year.

ULIBARRI

Absolutely, yeah. And then the last piece that I would point to in terms of our history was the construction of some of those major infrastructure projects. So the first of those was the Los Angeles Aqueduct in 1908. So this was when William Mulholland decided he wanted to grow the city of Los Angeles and went and bought a bunch of land in the Owens Valley — or stole a bunch of land in the Owens Valley, depending on how you look at it — and built an aqueduct, basically drained the Owens Lake and brought all the water to Los Angeles. Subsequently we built the Central Valley Project. That was a large federally funded project by the Bureau of Reclamation in the 1930s. And then the State Water Project in the 1960s. And all of these were really because people didn’t live where the water was. Now we have this giant infrastructure system that we’re very reliant on. If we were to suddenly lose access to any of those water sources, we wouldn’t necessarily have enough water to sustain our day-to-day life just on the water that’s available in any given location.

ORLOWSKI

We kind of got a taste of what it’s like to be suffering from an immense lack of water just in recent years when there was the drought, the severe California drought from about 2011 to 2016. Some of those years were the driest on record. So during that drought what were some changes that came about because of the severity of the situation?

ULIBARRI

So there were really two major changes. Well, three, I guess, really a psychological change. And, you know, this was very much in the news. It was very much something that I think your average Californian knew that we were in a drought. And so I think it did raise awareness more generally of the fact that California — that there are times when we don’t have enough water. The two major policy changes that I would point to are, firstly, there was a statewide mandate that cities had to reduce their water consumption. The general target was 25 percent. And most cities actually did a great job at reducing their consumption. And it was initially meant to be a short term, okay, just while we’re in the drought, you have to do this. But it’s actually been extended in a number of places. So most cities are still maintaining that 25 percent reduction in their per capita water use. The second major change was the passage of the Sustainable Groundwater Management Act, or SGMA. And this was the first statewide regulation of groundwater use. So prior to SGMA, there had been a couple of regions that groundwater was being sort of over-allocated, or there were large conflicts over groundwater, and those were regulated. But otherwise we were the only state in the country that didn’t have any limits on who could pump groundwater, or how much they could use.

ORLOWSKI

Wow. That’s incredible to think about, and just the sort of Wild West atmosphere that California had around groundwater until just a few years ago. Well, so I want to ask a bit more about that in a second, but first of all, did the drought end? And so are we still in a drought currently at this moment in time?

ULIBARRI

So the middle of the last decade drought did officially end. 2017 was a pretty wet year. And so that refilled our rivers, refilled our reservoirs and reset a lot of the metrics that we look at to determine whether we’re in a drought. The one place that didn’t fully recover was a number of our forests. So there, the trees generally take a few years to get back to the health that they had before the drought. So in a number of places, particularly in the Sierra Nevada, if you still have large swaths of standing dead trees, for instance. So this sort of ecological drought still hasn’t fully recovered. So that was then. We are actually, though, most of the state is back in a drought. When I looked this morning, 85 percent of the state was in moderate or a more severe drought. It’s nowhere near what we were prior. If you had looked for instance, in like 2015, pretty much 100 percent of the state was in severe or extreme drought, versus now it’s dry, but it’s not quite as dry.

ORLOWSKI

Well, getting back to the Sustainable Groundwater Management Act, as you noted, that was a huge change in how California managed groundwater, making it the 50th state to finally manage groundwater in some capacity for the first time. So what were some of the requirements of that legislation? How did agencies have to respond or what did they have to do because of that act?

ULIBARRI

So the SGMA is really focused on local level management of groundwater. So it’s not coming in and saying, okay, if you own a well, you have to get a permit, it’s not setting any top-down limits on how much groundwater can be used. Instead, the way that they designed the act was to say at the local level, groups of water users had to get together and form what they call a groundwater sustainability agency. And then these agencies would decide what they thought sustainable use of groundwater would be for their region. So they kind of set this sustainability target. And then to meet that sustainability goal, these agencies have to write what are called groundwater sustainability plans. And these plans basically document current groundwater use in their areas and put forward a series of proposed actions that they’ll do to reach that sustainability goal. So either actions that will reduce the overall demand, so the use of groundwater, or things that will help put groundwater back in the system.

ORLOWSKI

So I know it’s only been a few years, but have they successfully created those plans or implemented them at this point?

ULIBARRI

Some places, yes. Basically the state required that places that are in what are called critical overdraft — those are places that are using lots and lots of groundwater relative to how much gets put back in every year — those places were required to submit their plans by January of last year, so 2020. There are now the next round of groundwater sustainability agencies, places that are not in the severe category, but that still are using a lot of water — theirs are due, I believe, next year. 

ORLOWSKI

Well, and one of the methods that seems to be growing in popularity for managing groundwater is called managed aquifer recharge. Can you tell us, what that is and why is it becoming more popular right now?

ULIBARRI

Manage aquifer recharge is essentially when you deliberately try to put water back into groundwater storage. So you can think about a groundwater aquifer as a bank. Let’s say that you have a bank account. If it has some amount of money, and if you withdraw $500 a year every year it will go down, you’ll have less and less money. But if you put some money back in, that can bring back up your balance in the bank account. And most aquifers do have some natural recharge coming in from rainfall or seeping in from rivers or things like that. But if you pull out more water than that natural recharge rate, your groundwater level will drop. Managed aquifer recharge says, let’s deliberately put water into groundwater storage so that we can bring water levels back up.

There are a variety of different techniques to use it. You can basically sort of reverse a well. So we call that direct injection. You can spread water on the surface, on the ground surface, and let it seep in. There are places where they’re using it with agriculture. And so basically you use flood irrigation to water your plants and leave it on perhaps longer than you would naturally and let that seep into the ground. And it’s really popular partly because, you know, we’re using too much groundwater in many of these places that are regulated under SGMA, and generally, psychologically, it’s easier to find water and put it back into the ground than it would be to actually reduce groundwater use. You know, I say that somewhat cynically, but the other, other side of it is that MAR (managed aquifer recharge) actually can be a really valuable tool when you are in a place with such variable rainfall year to year.

So basically the idea is if you have a really dry year, there’s not that much surface water available. There’s not too much, you know, there wasn’t enough rain. So let’s turn to our groundwater. Let’s pump out a little bit extra this year so that we can keep watering our crops, drinking, etc. And then in wet years, when there’s lots of rain, it says, okay, instead of trying to use every inch of that rainfall, let’s deliberately let some of it go back into the ground so that we can bring our water table back up for the next time that we’re in a drought.

ORLOWSKI

Well, it sounds like managed aquifer recharge could be a potentially good way to account for the variability in water resources that will only grow greater with climate change. What threat does climate change pose for water resources in California? And what are we doing to start accommodating for that?

ULIBARRI

We can think about it that it’s going to make that variable hydrology more extreme. So we’re expecting, in terms of general rainfall amounts, we’ll have more extended droughts, so longer periods without precipitation, and then when we do have rain, it will be much more intense. So lots of rainfall in really short periods, possibly leading to flooding. That’s one side of things. The other one is just because temperatures overall are increasing, we’re starting to see more water in the winter falling as rain that historically would have fallen as snow. And that — even though we’re still getting perhaps the same amount of rain — that makes it a lot harder to manage because the dams and reservoirs we had built in the state were designed for the amount of snow that we had. It sort of melts slowly over spring time and the reservoir can fill up. Versus now, if it all falls in as rain, you need much larger reservoirs, or other ways to store that water that we don’t have right now. So that’s another place where managed aquifer recharge is coming up as a potential solution.

ORLOWSKI

And the water districts, the local agencies that really manage water resources at the local level will need to adapt to these changes resulting from climate change. And you’ve done some research looking at the plans that these agencies are creating for various purposes. So are they really looking at and planning for climate change according to the research that you’ve done?

ULIBARRI

Unfortunately, no. So we looked at a variety of different water management plans put together by urban water utilities, by irrigation districts and also by the groundwater sustainability agencies that were created under SGMA. And basically across the board with a few exceptions, they for the most part did not do a very good job thinking about the impact of climate change on their water supply going forward. So in some cases it was kind of saying, well, we use groundwater, therefore we always will have a good backup if climate change affects surface water supplies. Which is true in some ways, but if everybody else is also turning to groundwater, then that groundwater might not be there anymore. I guess I should clarify this as specifically agencies in the Central Valley of California. I don’t know for sure if you were to look in other regions, if they’re perhaps doing better, but they’re really not doing a good job thinking about how either those more extreme events or the change from snowfall to rainfall is going to be shaping their availability of water.

ORLOWSKI

Well, we started this conversation talking about the history of water in California, and you mentioned some of the huge floods in the 19th century that set the stage. And then we talked about the drought of more recent years and the potential for climate change to make both of those things more common. So when you look at the water system here in California, what do you see as its potential? Could we have a healthy, thriving water system here and what do we need to do to get there?

ULIBARRI

As you mentioned at the beginning, we’re one of the largest economies in the world, and we are the number one agricultural producer in the United States, number one manufacturing sector in the United States. And yet fundamentally, we as a state, we are a desert. And so the fact that we’ve managed to do this with very little water is actually quite impressive. The challenge is that, right now, that economic progress has come with a lot of environmental damage. So we’re seeing declines in lots of the fish species that are dependent on our rivers, for instance. And it’s also come with a lot of equity impacts in that there are communities that don’t have access to adequate drinking water supplies, despite the fact that we are such a wealthy state. And so thinking about a path forward, I think we need to figure out a way to sustain that economic prowess without further damaging the environment and making it more equitable, and doing all of that as climate change makes the water supply even more variable, even harder to manage.

So in terms of the how we get there, this is a couple of small ideas. First is the water rights system. I mentioned this at the beginning, where it’s kind of a first come, first served. So if you have one of the oldest water rights, you get to use your water first. And that really favors the agricultural sector because they were the first ones to set up and use water in the state. But the way that our system is set up is basically if you don’t use your full allocation, you actually lose it over time. And so there really are not good incentives to help agriculture become less water intensive. If they sell their water right, they don’t get it back for the future. And if they don’t use the whole water right, then they lose it, potentially. And so, you know, I don’t know the answer on this, I’m not a water law expert, but I think our water rights system as a whole needs some drastic retooling, if we really do want to put the incentives in place. 

Second, and a big one, is upgrading our aging infrastructure. So most of our flood control systems, most of our water supply systems were built in the early to middle 20th century. And so they are aging. We’re starting to see some failures. There was the incident at Oroville Dam with the spillway almost failing several years ago. And so I think really investing in that infrastructure. But as we invest in it, don’t just rebuild what we had, but instead use it as an opportunity to rebuild something that’s going to be more flexible and more accommodating of nature. So thinking about if we’re building for flood control systems, for instance, are there ways that we can actually maybe rewild some rivers and help use more of the floodplains to create habitat, create recreational spaces around them, rather than just making a big concrete channel.

And then lastly, I think, is around the planning piece. And we mentioned evaluating all of the various water management plans. And the regulations talk about, well, you need to think about climate change, and you need to think about ways to make your water system more efficient, and things like that. But then there’s no evidence really that the plans that all of these agencies are writing are then implemented. And so there’s a lot of great ideas out there, but if we could actually get them implemented and enforced — if the local level plans were enforced by the state, that would be great. And so that would take both some actual monitoring and enforcement, but also a lot of capacity building and funding from the state for local water agencies to move some of these activities forward.

ORLOWSKI

Professor Ulibarri, thank you for joining me today on the UCI Podcast.

ULIBARRI

Thank you very much for having me.