LISA: Welcome to Brainwaves, a podcast about big ideas produced at the University of Colorado Boulder. I'm your host, Lisa Marshall. If you haven't already, please like, subscribe and share our shows.
This week, we look into the really complicated history, and uncertain future, of water in the West.听
Will we have enough to keep up with a growing population?
Where and how will we cut back? And what are some of the cutting edge ideas out there? Like paying people to rip out their lawns or drinking recycled toilet water, that could help us conserve what we have.听
We will start things off with an interview with Doug Kenney, director of the Western Water Policy program at 抖阴短视频 Boulder Law School. Doug has written extensively on water-related issues, including law and policy reform, river basin and watershed level planning, climate change adaptation and water resources economics. Doug, welcome to the show.
DOUG: Thank you.
LISA: I'd like to start this conversation off with a really basic question, and that is: Anybody who's been skiing recently knows there's a ton of snow in the mountains right now, it's been raining this week, things are greening up. Looks like there's a lot of water out there. So just to, kind of, play devil's advocate: Why should people care about this issue?
DOUG: Well, you're right, it's been a very good year for water supplies. The problem is one good year doesn't offset many bad years, and the trend, over the recent decades, has been to get drier and drier in this part of the world. Most places in Colorado and most places in the southwestern U.S., water supplies are pretty tight, and they are a limiting factor on growth of cities and then the expansion of farms and one good year joy it your garden probably looks good, my garden looks good, but the trend is what we're worried about, the trend isn't good.
LISA: And looking forward, I've seen some projections that the Front Range population could double by 2050. If that were to happen, and we don't kind of address this water issue, what could that mean, just for people who live in the Front Range?
DOUG: People worry about running out of water and running out of enough water to sustain growth and to sustain existing practices and you know, it's not one of those things that all of a sudden you hit a point and you're out. It's kind of a gradual process where a water source that used to provide 100% reliability now provides a little less and so you kind of go down that slippery slope toward your risks start going upright incrementally. You also have this problem where the pressure on farms and the pressure to take water away from farming regions and move it to the cities continues. And that works fine for the cities, the cities by and large don't run out of water. What happens though, when the cities get nervous about their water supplies, they start buying up the water from agricultural regions and the impacts there can be pretty severe.
LISA: And just, kind of, aesthetically if you look at a places like Lake Powell or like Mead what's going on there?
DOUG: Lake Powell and Lake Mead there the two largest reservoirs in the United States. Very significant stores of water, and they were both full at the turn of the century, in the year 2000. Five years later they were half-empty or half-full, if you're the optimist. But they'd lost half their water storage, and that was significant in a lot of ways. But one of the ways it was significant was, it was visible. People could see that there was a problem. People could see that we were on a trendline that was pretty scary, and those reservoirs haven't rebounded. They haven't really gotten worse in terms of their storage levels, but they haven't gotten any better. And that worries a lot of people who are dependent upon the water from those reservoirs. The City of Las Vegas is a great example they get pretty much all of their water supply pulled out of Lake Mead. If Lake Mead goes dry you know that's a city of a couple million people who have lost over 90% of their water supply.
LISA: So there are some solutions in the works I want to talk specifically about, I know President Trump recently signed a bill authorizing a plan for seven Western states to take less water from the Colorado River. Can you just give a little historic snapshot on how we got here? I know it was a long time ago that we first decided how we were going to divide up that water.听
DOUG: So there were seven states that share the Colorado River and the river flows into Mexico at the end. So there's two nations and seven states that share this river. Many years ago, it was decided that in order to manage this river in a reasonable way, there needed to be some allocations, dividing up the water among these parties. And the big event happened in 1922, when the seven states came to an agreement amongst themselves about how much water each state would take. Then a little later in the 1940s, the U.S. and Mexico made an arrangement among the two nations. So those two agreements laid out the framework as to how much water each party was entitled to. Well, that's all well and good, except they allocated more water than actually exists. People have known for many years that this was done, but it wasn't a problem until people started using that water, trying to use all that water they were allocated. In the last twenty years, we've gotten to the point where all the water is used. There's no leftover water. And there are many parties, including the state of Colorado that says, "Hey, we're still not using as much as we were allocated, and we'd like to use as much as we were allocated. We'd like to use what we were promised."
And so that's where one of the problems comes in is, is everyone wants what they negotiated. Everyone wants what they were promised, But if everyone takes what they are promised, then we're at least ten percent, that's at least ten percent more than what the river actually has, and what the river actually has is in decline through the forces of climate change. We see a pretty sharp and pretty scary trajectory on the river in terms of the flows are dropping year by year. Flows so far this century are about 20% less than they were last century.
LISA: What's this new plan going to do and who will it impact the most?
DOUG: The plan you're talking about is called the drought contingency plan or the DCP. This is negotiated by the seven states, but all it says is that we understand that everyone can't take what they were legally promised. The system just physically can't provide for that. And so the question is if someone has to take less than they were promised, who is that person and what is the schedule for cutting back their supplies. The party that really gets hurt or that really has to take this biggest cutback as the state of Arizona, and specifically farmers in central Arizona. They are kind of last in the pecking order here, in terms of whose water is least reliable. And so this agreement basically says as the storage level of Lake Mead drops past certain thresholds, certain trigger points, then the water deliveries to central Arizona will be cut back by a specified level. Now there's some other parties that also have to share in the pain a little bit, but it's mostly an Arizona problem at this point. And the reason they agreed to that is because they knew they were going to have to take less water at some point anyway. And so the thought is, taking frequent small curtailments is less painful than infrequent but very large curtailment, and so it's not an agreement to be real happy about and say, oh we've solved the problem, it's a schedule for allocating the pain. And you know, if you have a schedule, then you can make other arrangements and try to do other things, but it's not really a happy ending, it's a necessary step forward.
LISA: So if this is not a silver bullet, obviously just from your perspective, in the about 45 seconds we have left, what else should we be thinking about in terms of solutions?
DOUG: I mean there's only one decent solution is that across this Basin we have to use less water. (sic)
LISA: Thank you so much and we appreciate having you here.
DOUG: Thank you.
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LISA: Water security of course is not just an issue along the Colorado River, communities around the world and around the country are starting to look at ways to recycle or reuse water. Some are even going from this [Toilet Flush] to this [Water being poured] Brainwaves Molly Pfannenstiel has the story.
MOLLY: Toilet to tap. It's a phrase water engineers don't love, but it's basically accurate and as water resources in the West grow more scarce, this decades-old concept, more technically known as direct potable reuse or DPR, is growing, shall we say, more palatable.
JASON: The beer is delicious; you know, actually, they made a pilsner, a light beer and that was by design, that it was a very light and crisp and refreshing beer. And not, you know, you're not going to make a stout or something with this type of beer, with this type of water. The whole point is to showcase the purity and the clarity of the water.
MOLLY: Jason Aslean is the president of Water Reuse Colorado. That's a trade association advocating for safe, appropriate ways of recycling water, including direct potable reuse. He's in his office in the Interlocken Technology Center in Broomfield, Colorado, showing off some beer, a bottle of wine, several different varieties of bottled water, all crafted from DPR water and served to consumers at demonstration projects around the country. The goal? To help people overcome the undeniable "ick" factor associated with that term, "toilet to tap."
JASON: It definitely has a stigma, it's not inaccurate, but at the same time, I think all water has gone through that process. And all water is, you know, the same water that's been recycled for billions of years. And so it's really a matter of what processes that water has gone through, and what's the true water quality.
MOLLY: By definition, DPR water is produced without an environmental buffer. Normally water moves from your toilet or shower or other drains in your house to wastewater treatment facility, then onto a stream or reservoir where it is diluted some more. Then perhaps on to another facility for further treatment. With DPR, all treatment happens in one place, transforming wastewater to drinking water without moving it around, which can be costly, and without losing water to evaporation or leakage along the way.听
JASON: So the benefit right now is that you're able to you know fully utilize every drop of water and minimize the amount of handling, and you know, discharge back to waters. So it goes through a relatively, you know, standard wastewater purification process, and from there, there's advanced treatment beyond that.
MOLLY: The concept has been around for decades, with the first DPR facility coming online in Windhoek, Namibia, in the 1960s. But it's been a hard sell in the U.S. There's only one facility here, launched in Big Spring, Texas, in 2013 after Mother Nature literally dried up the town's namesake.
JASON: It was triggered by an extreme drought and an absolute necessity, they had no water.
MOLLY: Five years after its inception, the Big Spring system reportedly saves the water district about 1.7 million gallons per day. And thirsty communities across the country including Castle Rock, Colorado, are seriously considering similar systems.
JASON: It certainly could happen in Colorado, depending on which utility chooses to embark on it and whether they have the water rights to do it. The next step would be, you know, to secure the funding and to send to really show, you know, a need, a strong need for embarking on quite an adventurous task, I guess. I mean, I think a lot of it is important to understand that a lot of people are looking really closely and spending a lot of time and a lot of effort to make sure that the water treatment that goes into the processes and the public outreach all come together to make sure that the water is as safe, if not safer than what everyone's used to drinking on a daily basis from the tap.
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LISA: One community on the edge of all this: Sin City. The population around Vegas has grown more than 14% since 2010, according to census estimates. At the same time, Las Vegas has used innovation and plain old cash to decrease its water use by some impressive amounts. Brainwaves' Paul Beique looks at what's going on, and how science will help these drought prone communities keep a handle on their water use in the future.
PAUL: Joining us now is John Ensminger, general manager of the Southern Nevada Water Authority, and the main negotiator for Nevada on all Colorado River matters. He's also a graduate of the University of Colorado Law School.
We are talking about managing water resources in an era of tremendous growth. Are growth limits on cities or states of possibility in the future?
JOHN: I think depending upon how they grow. I think what we've demonstrated in Las Vegas is that you can actually use less water and still add to your population and grow your economy. Since 2002, our population here in Southern Nevada has increased by 46% and in the same time period, our Colorado River consumption is down 25%. So, I think a lot of people have this direct correlation between population growth and increased water use in their mind, but that simply doesn't have to be the case.
PAUL: How does Las Vegas do it? It has a reputation听for being very frugal with water during a period of growth.听What are the strategies that Las Vegas uses to reduce its water use?
JOHN: Well first, we are fortunate with our geographic location next to Lake Mead that enables us to have a hundred percent indoor recycling. If it hits a drain in Las Vegas, we treat that water, we put it back into Lake Mead and then we can take out the exact same amount again. So we have a very tight system, we have less than 5% unaccounted for water, and we spend millions of dollars every year to make sure that over 6,000 miles of pipeline aren't losing very much water at all. So essentially, I think, really, we put the capital into making sure that we have a really tight system, and that's what's allowed us to have the kind of growth here in Southern Nevada we have and still use less water.
PAUL: What are some of the strategies that you use with homeowners to get them to conserve water?
JOHN: Well, really, our flagship program is our water-smart landscape program. That program since 2002 has spent about $250 million paying people to remove turf. And that has been the number one thing that has driven down the consumptive use of Colorado River water in Southern Nevada. But we don't stop there. We do, you know, pool cover programs. We engage, you know, at all levels of our education system. We do indoor plumbing fixtures and rebates on high efficiency, you know, washing machines and dishwashers. So really it's just a multi-faceted program that stresses a culture of frugality in the Mojave Desert.
PAUL: And it sounds like you get pretty good buy-in from the population, is that right?
JOHN: We do, and I think you know a lot of that credit you know goes to our elected leaders. You know, they've absolutely supported you know setting rates in a place that allows us to do these conservation programs. But a lot of it is simply, the community having Lake Mead in our backyard, they can see for themselves the 140 decline in the lake since the turn of the century. So the drought is a very real thing to Southern Nevadans in a way that it might not be to some of the other 40 million Americans that they share this river with us.
PAUL: Nevada is doing a good job conserving water today, but how do we know how much water we'll need tomorrow? To help us answer that question, we turn to an expert.
CARLY: My name is Carly Jerla. I work for the Lower Colorado region of the Bureau of Reclamation and I am a program manager there working on Colorado River policy and research initiatives.
PAUL: What work are you doing involving the Colorado River?
CARLY: We are primarily developing and applying the modeling tools for the basin that are projecting system conditions. We're primarily working on a mid-to-long term, so two year and beyond projection simulation looking at how the Colorado River performs under various futures of hydrology demands and evaluating policies and providing that information to decision makers.
PAUL: In general, what does that picture look like are you confident that the Colorado River can do all we needed to do or are we in big trouble here?听
CARLY: Well it depends on what time scale you're looking at so I know that one of the topics of this podcast has been the drought contingency plan of the DCP, and our office was pretty heavily involved in helping to develop that policy from a technical standpoint, and looking at how that policy performs throughout the duration that it will be implemented in through 2026. So the DCP does performs (sic) well in terms of really reducing the risk of catastrophic things happening, reaching those critical reservoir elevations during that time. But as you get farther out, the picture starts to get more complicated in terms of uncertainties that stem from climate change, hydrology, changes in hydrology, but also changes in demand. In general, the more you look out the more uncertain things get, the more complicated the future is.
PAUL: You're using the word uncertain a lot does that just mean bad, it's looking bad?
CARLY: Not necessarily, uncertain also means you know periods of high end flows or very wet futures. Uncertain means that there's a wide range associated with how things could play out, and when our thinking about future hydrology that's definitely the picture. We know that, absolutely, climate change is contributing to our hydrologic picture. It's exacerbated this current drought. We've seen things like higher temperatures, increased losses and evaporation, evapotranspiration, but also more intense precipitation patterns, changes in precipitation distribution. And so all those things have to be accounted for when we're trying to project what future hydrology scenarios might look like and how that might impact how we operate the system.
PAUL: And so when you're looking at this what is jumping out at you right now?听
CARLY: We look at various scenarios of the future, but in terms of water use, it's a future of increasing water use. And there's different rates at which that use increases, but in general the trend is increasing water use. And so you couple that with your hydrology side, or the supply side, and instances of wetter futures, but for the most part it's a drier future that's coming out of our hydrology projections because of increasing temperatures. So a drier future coupled with increasing demand leads to more stress on the system, declining reservoir elevations, declining flows and the streams which impacts really all of the resources that are dependent upon the Colorado River.
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LISA: That's it for this week's episode of Brainwaves. If you found it interesting, please like and subscribe. Also, check out our next episode on life and death in the age of social media. I'm Lisa Marshall; today's show was produced by Dirk Martin and Paul Beique; Andrew Sorensen is our executive producer; Andres Belton created our introduction.听