Colorado River water allocation policy is an extremely complicated field to navigate. That, in part, is why the Colorado River is known as the most litigated river in the world. But researchers, policymakers and water managers have taken a more collaborative approach in recent years. Those collaborations are made more critical by the increasing risk drought poses to the Lower Basin.
Colby Pellegrino is the Deputy General Manager of Resources for the Southern Nevada Water Authority and the Las Vegas Valley Water District. In her current capacity, she is responsible for the management of the Water Authority’s water resource portfolio, which includes protecting Nevada’s interests and rights to Colorado River water through interstate negotiations, developing regional water conservation programs, managing groundwater resources, and water resource planning.
On this episode of Discover Science, hosted by associate professor of political science Elizabeth Koebele, Colby Pellegrino guides listeners through the complicated process of allocating water to millions of people in the hot, dry southwest, and why the city of Las Vegas is a model for water conservation efforts.
Discover Science: Colby Pellegrino on the water challenges of the Colorado River
Political science professor Elizabeth Koebele is joined by Discover Science Lecture Series speaker Colby Pellegrino.
About the lecture series
The Discover Science podcast is an offshoot fo the public lecture series by the same name. The Discover Science Lecture Series was founded by the College of Science in 2010, with the goal of bringing the country's top scientists to the University to share their knowledge, research and wisdom with the community.
"Science encompasses a wonderfully diverse collection of explorations into the unknown. We invite science lovers and the science-curious to join us and experience the extent of the science universe as the best scientists on the planet visit the 性爱五色天, Reno for our Discover Science Lecture Series," Jeff Thompson, executive vice president and provost of the University and founder of the Discover Science Lecture Series, said.
Past speakers in the series include astrophysicists Michio Kaku and Neil deGrasse Tyson; Robert Ballard, who discovered the wreck of the Titanic; and Bill Nye the Science Guy.
Elizabeth Koebele
Hi, everybody. My name is Elizabeth Koebele, and I'm a professor of political science and the associate director of the Graduate Program of Hydrologic Sciences at the 性爱五色天, Reno. I know that sounds like a strange combination, but my research lies at the nexus of politics and water, which happens to be the topic of this episode of the Discover Science Podcast, a spinoff of the Discover Science Lecture series.
The series is founded by the College of Science in 2010, with the goal of bringing the country's top scientists to UNR to share their knowledge, research and wisdom with the community. I'm thrilled to be joined today by our guest, Colby Pellegrino, an expert on the allocation and management of the Colorado River. Welcome, Colby.
Colby Pellegrino
Hi. Thank you for having me, Elizabeth.
Elizabeth Koebele
Yeah, our circles have overlapped quite a bit over the years, and I'm really excited to meet you in person. So we're grateful that you're on the podcast today. So to start off, I was wondering if you can state your full title for our listeners.
Colby Pellegrino
So I am the Deputy General Manager of Resources for the Southern Nevada Water Authority.
Elizabeth Koebele
Great. And can you tell us a little bit more about what that entails?
Colby Pellegrino
So as deputy general manager of resource, simplest put, my job is to make sure our community of 2.2 million people has water, now and into the future. So I'm responsible for all of our water supply planning, all of our water conservation programs, our scientists that support both of those efforts, our environmental permitting, doing adaptive management on the Colorado River, as well as all of our public information staff that helps get the word about water conservation out into the community and the Las Vegas Springs Preserve, which is a little bit of a museum and cultural center, surrounding the original Springs and Las Vegas that were a stop on the old Spanish trail.
Elizabeth Koebele
Wow, you have a lot going on across all of those roles. Thinking about water policy in southern Nevada seems hard enough, but understanding how it fits into the big picture of Colorado River management is a whole other animal. For our listeners, the Colorado River provides water to over 40 million people across seven U.S. states and two states in Mexico. It also supports over 5 million acres of productive agriculture, numerous other industries and so many of the environmental and recreational assets many of us Westerners love. Colby, can you tell me a little bit about how much water Nevada gets from the Colorado River and how it's used in southern Nevada?
Colby Pellegrino
Sure. So the allocations of Colorado River water occurred, really, in the early 1920s. The compact was originally splitting water between the Upper Colorado River Basin and the Lower Colorado River Basin, where there’s seven and a half million acre feet to each basin. And for those not familiar, an acre foot of water is somewhat of an arcane way that we measure large quantities of water. One acre foot is about 325,000 gallons of water. If we want to think of it in terms of use, it's about what three average Las Vegas households would use for a year.
Within the lower basin, that seven and a half million acre feet is split where California gets 4.4 million acre feet, Arizona gets 2.8 million acre feet and Nevada gets 300,000 acre feet. Then on top of the allocations in the lower basin, there's another million and a half acre feet allocated to the country of Mexico. For Nevada's part, almost all of that water is used in the urban areas of Clark County, serving the cities of Las Vegas, Henderson, North Las Vegas, unincorporated Clark County, Boulder City and Laughlin. We also do have the Fort Mojave Indian Tribe, which has access to Colorado River water, and they primarily use for farming at the very southern tip of the state.
Elizabeth Koebele
So one of the things that we hear a lot about in the state of Nevada is how the Southern Nevada Water Authority needs to really use their water efficiently in order to make that small amount, that 300,000 acre foot, acre feet that you talked about stretch far enough to meet all the needs of these communities. So I was wondering if you could tell me a little bit more about the conservation efforts that your agency engages in.
Colby Pellegrino
Sure. We have a very holistic water conservation program, one of the most comprehensive in the nation. Our water conservation is different than some other cities, and I'll describe that first. Lake Mead is right adjacent to our community, and we're a fairly young community, so we have centralized sewer on nearly all of our homes and businesses, and water that's used indoors is treated and returned back to Lake Mead. And that doesn't count against that 300,000 acre foot allocation. Only what we deplete from the river counts, and that is primarily outdoor water use within Southern Nevada. Our second largest use that we really target is probably evaporative cooling, and together those are the two biggest uses of water and we call them consumptive use. That's what, where we're permanently consuming the resource. There's nothing left for us to reuse or return. So when we talk about our water conservation journey, it's primarily focused on those consumptive uses. We've been incentivizing all sorts of different water conservation activities, from removing unused grass, to upgrading your sprinkler irrigation clock to something that uses better technology. We also provide rebates for leak detection devices. We're the first agency in the nation to do that, as well as some more restrictive measures. So we have advanced building code throughout the years to ensure that new people using to, moving to southern Nevada are using water as wisely as possible. So starting in 2004, we changed the amount of grass that people were having to have in their property and going to no grass in the front yard and only 50% grass in the backyard. Now, why is that important? Because grass uses about 300% percent more water than desert friendly landscaping. Our grass uses about 73 gallons per square foot, whereas desert friendly landscaping uses about 18. We've taken that one step further, and now turf is only allowed in schools, parks, and cemeteries. There's lots of beautiful options, including artificial turf, that save a lot of water for our community, and that’s going to be the standard of the future in Southern Nevada.
Elizabeth Koebele
It's amazing to hear that Southern Nevada is such a leader in water conservation in the Colorado River Basin, especially given the fact that this region has faced historical droughts, and now climate change is putting new pressures on our water supply. So I was wondering if you could talk a little bit about how these kinds of changes are affecting Southern Nevada and what this means for the Southern Nevada Water Authority and the citizens of Nevada in the long term?
Colby Pellegrino
That's a great question and it's very comprehensive to address. Climate change is impacting our water resources in two ways, both our water supply and our water demand. One of the hardest things that we have in educating the public is that the amount of rainfall and the temperatures locally affect our water demand, the amount of water that people in our community use, but they don’t really impact our water supply, because the water supply in Lake Mead is coming from the Colorado River, of which over 80% of the runoff comes upstream of Lake Powell on the other side of the Grand Canyon from us.
And when you look upstream in the upper basin, you're really talking about how the Rocky Mountains are being impacted by climate change. So what we see on the Colorado River front is multiple things. As the atmosphere warms, it has a greater carrying capacity for water. So we have increased evaporation from the natural system. We also see that because of that warming, the snow is melting sooner. That means the growing season starts sooner. That means there’s more evaporation, that means farmers start farming sooner, and so there’s a lot more water being used, both in the natural environment and in the built environment as a result of climate change. Together, the increased temperatures and the impacts that it have are reducing our overall water supply. And we talk about this last 23 years being one of the worst droughts in recorded history. And for a long time we kind of have done ourself a disservice by calling it a drought because it sounds really temporary. It sounds like something that's come, and if we wait long enough, it's going to go away. And what we're really experiencing on the Colorado River Basin is a phenomenon called aridification. That means that our climate is permanently changing, that these increased temperatures are going to fundamentally change the amount of runoff that we're seeing. And what we're calling a drought now, this driest 23 years that we've seen may very well be the wettest 23 years of the next 100 years, so we need to be prepared that this dryness might not be temporary and it might not be the worst that we see.
Then if you shift over to our water demand, we have a whole host of different things that are impacted by the local climate, local weather. So the biggest thing that we tried to get our citizens to do to be a part of the solution for water conservation is to follow their seasonal watering restrictions. We need to recognize that any of our landscapes, regardless of whether it's trees, desert plants, cacti or grass, need significantly less water in the winter than they do in the summer, and that that water demand changes throughout the year. So what we know is that air temperature in the Las Vegas Valley is getting hotter, too. We anticipate that we're going to see much more above-100 degree days. And what happens when it's above 100 degrees? People water their landscape more.
And so we have to be continuing to message the community about the right amount of landscape watering, about not overwatering our plants, really remembering to change your watering clock to go along with the seasons, but also adapting the community to the drier future. So one of the things that we started to do is look at our plant and tree community and say there are things that have gone really well here in the past that as we get hotter, are not an example of that is like Afghan pines. They're one of the most popular shade trees within the valley, but they are going to be severely impacted by climate change because we're kind of right on the border of the temperatures zone they like. And what happens when a tree dies? People water it more, but that tree's not dying because it doesn't have enough water. It’s dying because it’s too hot. So we're trying this multi-pronged approach to really message the community about the right way to use water.
Elizabeth Koebele
Great. So you talked a little bit about this complicated allocation system on the Colorado River, and that leads to all of these competing demands both within Nevada and across all of the states and across even countries in the Colorado River Basin. And to me, it's no surprise that we hear the phrase, “The Colorado River is one of the most litigated rivers in the world.” But I wanted to ask you, my research has shown that a lot of the entities in the Colorado River Basin have collaborated on policies over the years. They've been able to come together, find common ground, reached consensus on solutions that could potentially lead to better outcomes with the idea that if we all work together, we might come out better in the end than we would if we were all continuing with this really litigious path. And so I was wondering if you could talk about how the Southern Nevada Water Authority is collaborating with other entities in the Colorado River Basin, whether that be the federal government or states or tribes or NGOs to reshape some water policies in order to get Southern Nevada to be more sustainable in the future.
Colby Pellegrino
So I think the most important thing, when we talk about river policy, to recognize is how small of a water user southern Nevada is. We have 1.8% of the allocated water on the Colorado River. So we cannot solve this problem alone. You could wipe southern Nevada off the map and we would not change the trajectory of our reservoirs. We might slow it down a little, but we have to have partnerships, we have to work together. And we are often monikered the most litigated river in the world. And that really relates to some of the early years on the river, that there was 60 years of Supreme Court battles between Arizona and California over essentially how shortages would be borne. And so we've generally moved away from that in recent years. In particular this century, there's been sort of this hallmark of state cooperation. And what it's really founded on is that we do have this really complicated web of laws, decrees, federal actions, records of decision that define how water is used, who gets cut when and the only way as a water manager that we have certainty on what we get to use and when, is to stay out of court. If we go into the courtroom fighting state to state, there's one thing that’s for certain. Everybody’s going to get something less and everybody is going to get something that they're probably unhappy with. I don't think there's any clean winners or losers. So we have this sort of compelling reason for all of us to come together and cooperate. And that’s certainty. When you're managing the water supply for 2.2 million people, what we want to know is how much water we have available to us, when, that's what allows us to plan. That's what allows us to ensure that our community has a sustainable water supply. If we know when our reductions are coming and what volume they are, we can make sure we have the contingencies in place or that our water use is low enough to deal with the shortages that may be coming. So it's incumbent upon all of us, if we want that certainty, to come together and be part of the solution in crafting policy that works for a broad range of interests.
Elizabeth Koebele
I feel like right now, almost every day when I look at the news, there's a new story about Colorado River policymaking, and it can be a little hard to keep track of things. And so I was wondering for our audience, if you could just kind of give us an overview of a couple specific processes that you're working in or things that you're looking forward to on the Colorado River as far as management?
Colby Pellegrino
Sure. So I think most people would find it ironic that at the turn of the century in 2000, there still had not been a shortage in water supply in the lower basin states California, Arizona and Nevada. The upper basin states are a lot different than the lower basin states. So when we look to water users in Utah, Colorado, New Mexico and Wyoming, the upper basin states, most of the large reservoir storage sits below them. So somebody taking water directly off a tributary experiences a lot more volatility in their water supply. All of the lower basin states and Mexico get their water from Lake Mead, and Lake Mead is immediately downstream of Lake Powell. So it wasn't until 2007 that we finalized guidelines for how we share in shortages. And then this drought really challenged that policy, and we had to supplement it several times with different actions, such as the Drought Contingency Plan or the 500 Plus Plan, different things that were taken to try and proactively or voluntarily put more water in Lake Mead so we could avoid this critical reservoir elevations that really challenge our ability to reliably deliver water. All of that policy is set to expire in 2026. So we've already begun the process as states and as the federal government to start renegotiating the policy that governs shortages on the river. When we look back at this time last year, we had a really good, wet winter, as did most everyone around the state. It was very helpful up here in the Sierras and it was very helpful for Colorado River supply. But prior to that winter, we were looking at having to take really drastic reductions in a really short period of time in order to adapt to how low reservoir conditions had gotten and how inadequate the policy that we had drafted was at those extreme occurrences because the policy that we crafted was resilient for over 90% of the hydrology that it was designed around, and we ended up in that bottom end that really drove Lake Mead down very quickly. So this last year gave us a bit of reprieve, but there is a smaller policy effort going on that really aims at making sure we have enough water in our reservoirs while we renegotiate. Let’s avoid the catastrophe in the short term while we figure it out in the long term. That plan right now is out for public review and has a proposal in there that was put forward by the lower basin states to keep 3 million acre feet of extra water in Lake Mead to help ensure that we don’t hit those really critical reservoir elevations. There's all sorts of other little things that are always happening, but our system is generally being challenged right now by these reservoir levels that we've never experienced and by climate change and drought. One example that I'll give is that within the Glen and Grand Canyon ecosystem, we have smallmouth bass for the first time. And so the Bureau of Reclamation, together with the Park Service, right now is beginning a process to say, how do we deal with smallmouth bass in that area? Because they're eating endangered fish. So we need to look at really all the different ways that climate change is impacting the system and find ways to work together.
In the interim, I would say that there's federal funding in a magnitude that this basin has never seen, available right now. The Bureau of Reclamation has done solicitations on ways to bring in both short term water supplies, as well as longer term water savings programs. And they're evaluating those proposals right now. And we're excited to see, with such a big infusion of federal money, what we can really do to fundamentally change the way water is used in the basin, which leads to more collaboration, leads to more water users working together, comparing notes. ‘Oh, wow. I didn't realize you could save water by using that technology. Maybe we should try that technology.’ So there's a lot of information sharing going on right now, and it's a really exciting time to be a water manager.
Elizabeth Koebele
I was wondering if you could tell me a little bit more about some of the recent water conservation programs that you've helped implement in Southern Nevada.
Colby Pellegrino
So if we give a little bit of background, Southern Nevada has done a great job conserving water. But what we saw about the 2018-2019 timeframe was that our water use conservation was kind of becoming stagnant. And then we got really scared during the COVID year, which is ironic because you would think with our economy shut down and you know, having The Strip closed, that our water use would be lower, and it wasn’t. It was higher. And so we realized that we really needed to get back into our community and figure out the right ways to conserve water. So we've implemented a whole host of new conservation programs sort of over the last 2 to 3 years.
The first one that was really major was the passage of AB 356 in the 2021 legislative session. And what that bill did was said, we need to remove nonfunctional turf from our community by 2026. So what’s nonfunctional turf? It's grass that doesn't have a recreational purpose associated with it. It's all over our community. There's thousands of acres of it. And let me give you an example. A traffic circle. If you’re riding through a roundabout, the middle is landscaped in grass. There is no one riding their bike, making a picnic, playing football in the traffic circle. Or similarly turf on the islands in a parking lot. But it's a little more nuanced too, like at a park. Generally you think all of the turf at a park is recreational. Well, what about the turf that goes right up to a four-lane road? Nobody's using that part of the park for recreation. Or turf that’s just in the moniker area where there’s a big sign out front, but it's totally separate from the rest of the park. So that's what AB 356 said needed to come out. And then we had a citizens’ committee that helped us define what that turf is and we’re on the road to taking it out.
Another one on the legislative path was AB 220 that passed the legislative session that ended in 2023, and what that focused primarily on was septic systems. So we do have most of our community connected to centralized sewer, and we're getting that water back into Lake Mead. But as the valley grew, the water system advanced quicker than the sewer system. So there are septic systems in pockets throughout the valley, where the water that they receive may be Colorado River water, but all of their wastewater generated in their home or business is just going into the ground. So that bill was aimed at stopping the proliferation of septics and creating a way to ease the financial burden of folks that want to participate, to connect to the central sewer system. Similarly, within our own backyard, we've taken on a whole host of additional efforts surrounding water conservation. The first is probably reducing golf course water budgets. So our golf courses were allowed to use six acre feet per acre and we cut that down to four acre feet per acre. About 70% of our golf courses were already compliant with that, and another 10% were a stone's throw away from it, so some small modifications to get them there. You're no longer allowed to build a new golf course in southern Nevada. Now that's codified across all of our jurisdictions.
We have taken the step of saying there can be no new turf except in schools, parks and cemeteries. So even in new single-family homes, you cannot have live grass. If you want a grass playing area, it's going to have to be artificial turf. And plant some beautiful shade trees around it and save that 73 gallons a square foot that grass would use. We've also put a limitation on pool sizes. You cannot have a pool over 600 square feet. And finally, we took an evaporative cooling moratorium. So many of our large buildings are cooled with technology that uses water to make the building cooler. And this one was a little bit hard for us to work through, because a lot of our big properties like strip resorts have all of these different guidelines that they use to rank their environmental sustainability and governance, we call them ESG, metrics. And so those are all based on carbon footprint. They're not based on your local water resource or water supply. And they're these big international metrics for what they’re doing.
So there's a couple of different sort of international organizations that brought about this idea that for corporate governance, we need to start benchmarking how well we are at being a corporate citizen as it relates to climate change and sort of evolving social justice issues and being good corporate citizens. And so there these metrics that are made that are trying to be sort of one size fits all on the international scale for tracking our progress. And one of those things that's consistently tracked is the carbon footprint, and that tends to be the major driver. What we found is that there's a lot of these different ranking agencies that would like to bring in water. But water is not a one size fits all from community to community. So what makes sense in southern Nevada with no evaporative cooling may not be what makes sense somewhere else, but they have significantly more water available to them. We have plentiful sunshine. We can create great solar electricity and that's one way that we can deal with, in a sustainable way, some of the increased needs that may be there from changing cooling technology, but water has been very hard to make an entry into these metrics because it's very hard to establish something that really makes sense across a wide range of communities.
Nobody wants to take out water-based cooling and put in something that's going to use marginally more electricity because it would hurt that metric. So we had to work to really educate the community about it and then we were able to implement a moratorium. So there is no new evaporative cooling technology going into our valley right now, and that’s going to allow us some time to figure out what other technology works well. And that lead time is really important for new development because mechanical cooling takes up significantly more space than evaporative cooling, so our architects and our engineers need to have some notice so that they can appropriately plan their property to fit in that cooling technology that does not use water. So that's a sampling. I hope I didn't leave anything major off that we've done.
Elizabeth Koebele
Just to follow up on that, you mentioned that during COVID when The Strip was closed, you actually didn't see a huge reduction in water use. And I think that might surprise some people. I think we hear the perception that all these hotel rooms and fountains and things like that that might be around The Strip are so thirsty and use all of these water resources. But it sounds like that's not really the case. And so I was wondering if you could talk a little bit more about kind of that misperception.
Colby Pellegrino
That's great. And it's a, it's a huge misconception within our community and and more broadly as well from people that look at our water resource picture from outside. So again, because we have centralized sewer, every shower, every faucet, every restaurant that’s dumping, you know, the water in your glasses down the drain, that's all coming back to Lake Mead. So our consumptive use of water did not decrease in the COVID year.
What was really wonderful about that from a educational standpoint was it actually helped us figure out how much water the cooling systems were using at the hotels, which is really hard for us to get at. But having the hotels unoccupied, then that was the first time that we could really look a property and say, okay, how much is the cooling system used? And we were really surprised at the amount of water reduction. It was significantly less than we thought it would be. And some of that is because they still have to flush their water systems and not get stagnant water. But a significant portion of the water use that was there was their cooling systems. And so it gave us an interesting way to find out some data about how people used water.
Just because we’re talking about COVID, there was another phenomenon that we think happened but don't have a lot of great data, and that was people were at home in close quarters for a very long time and they started using their outdoor spaces in different ways and we saw our single family residential water use jump up significantly and we had people say, it's because of new homes. And we actually did some, some data analysis and, on a per account basis, our water use was up. So what we think was happening was that as people were home, they were deciding to be in their backyard to take a meeting in the spring of 2020 or going outside more to maybe get away or maybe just experience something different than their four walls. And that resulted in people adding more water to their landscapes or relandscaping during that time. So we had to use that time to focus on the message about how to use water wisely.
Elizabeth Koebele
So you mentioned before that so many of the policies that govern how water is allocated to states expire in the end of 2026 and that you're embarking on a process along with folks across the federal government, other states, to try to think about how to revise these rules for the future, knowing that many places in the basin are likely to experience that aridification that you talked about, to experience less water availability. So what are some of the things that you think are going to be the hot button issues in these negotiations post-2026 that might either cause conflicts between different groups or might be places where stakeholders can actually come together and find some common ground?
Colby Pellegrino
The hot button issues, I think, are everywhere. Because what these guidelines are really about is how everyone uses less water. And so you can cherry pick the piece of law or the piece of policy that you think is the most important that has the least impact on you as an individual water user. And so in order for us to craft policy that everyone agrees to, we kind of have to find something that makes everybody a little unhappy and everybody happy at the same time. We need to be able to craft solutions that our elected leaders, our appointed leaders our agency heads, the people responsible for both agriculture and urban can take to their elected boards and say, this is sound policy. It may not be everything we want, but it's a good deal for us. That's what keeps us out of litigation. But again, the crux of this issue is everyone having to use less water. And so I think that there will be conflict between different water user groups if we allow it. I think there will be conflict between the upper basin and lower basin if we allow it. I think there could be conflict between different water use sectors. And I think the only way we get around that is to try and craft policy that looks a little bit equitable to everyone. We have to pay our respects to the law and the things that people have agreed to or agreed not to or have given up. But we also need to recognize that the magnitude is so large that everyone has a little bit of responsibility in dealing with this. So I think that there's the ability for a ton of conflict, but I also think there's a lot of reason for us to work together, because ultimately the only way that we find common ground is for the river to be sustainable for everyone.
And if I could just give a note, like an ode to the short-term policymaking, I mentioned that the plan for review by the federal government right now has 3 million acre feet of conservation occurring in it. So 400,000 acre feet of that is coming from California, some of it from the most senior water users on the river. So when you sit down and you ask them, ‘Why did you come to the table voluntarily to do this?’ The answer is, ‘Because we go out of business if Lake Mead goes dry, too.’ So we have to find a balance between what our water users and stakeholders are willing to tolerate and the recognition that if things get really bad, we're out of business too. So we have to come together and be a part of the solution, or else letting Lake Mead go dry is bad for everyone.
So I hope that there's enough work by our scientists, by our Colorado River modelers, to show that those threats are real, that if we continue with the level of reductions we’ve had before, we cannot be sustainable. And I hope that that's enough to compel people to the table. I think the other place that will have conflict if we're not careful, is with our tribal communities. The way that tribes have been included in the past is probably not the way the policy and governance of the river would be crafted if it was done today, but we need to find a way for tribes to have a voice in river management that's meaningful, that's not just consulting with them. The tribes control a significant amount of water on the river, and they have some real heartstrings, for lack of a better word, to the river itself and the life that it brings to the desert southwest. And we could all learn from some of the tribal values on the river. So I think it really is incumbent upon everyone to figure out a way to love thy neighbor and to work with them going forward.
Elizabeth Koebele
Yeah, I think what you're saying really hits the nail on the head as far as the conversations I've experienced about the river, this recognition that we all lose in the end if we can't work together, whether that's letting Lake Powell and Lake Mead go dry and losing those assets that we, we love and enjoy and need for water supply on the river, or whether that's our inability to produce hydropower. Everyone loses if we don't all give a little. And so I think it's really important the, the examples you've pointed out, of places where people have come together, because they recognize that the Colorado River, as divided up as it is, it's really one big system. And what one person does in the upper basin does affect what happens to someone else in the lower basin and sometimes vice versa, so I think that that's a really important message to take away and to also just keep in mind for these future negotiations.
Colby Pellegrino
Absolutely.
Elizabeth Koebele
Great. Well, there's so much that you are doing in relation to the Colorado River Basin, it's hard to get it all in these conversations. But we really appreciate you taking the time to walk us through so many of these different processes. Just to close out, I was wondering if there's anything else I didn't ask about that you'd like to tell our listeners about the Colorado River before we end?
Colby Pellegrino
You know, I think that the Colorado River sometimes gets a bad rap, that we haven't done enough, that we haven't been bold enough. I would say, to look at it from a different light. I think we have a really strong history of cooperation and the issues that we're facing challenge every sector, they challenge every water user, they challenge every water use type, because everyone is going to have to use less. And our ability to take that on through the massive political network that we have is challenging sometimes. But there's a lot of people aware of the situation. There's a lot of eyes on the river right now, and I think that there is a lot of room for us to be successful if we can work together and be creative. I'll just do a little, I know you asked about the Colorado River, but I’ll just do a plug for Southern Nevada. We've implemented, as we talked about, one of the most comprehensive water conservation programs in the nation, and we've shown that it can happen. Our peak water use year was 2002. We pulled 325,000 acre feet of water off the river. This year, we're expected to pull less than 200,000 acre feet of water off the river, and during that time we've added 750,000 more people to our valley. So not only is our overall use decreased by a third, but we've done it while we've continued to grow our economy. And while we like to toot our horn about conservation, the fact of the matter is we're seeing this across Colorado River communities, that our friends in California and Arizona are seeing the same thing, that we've been able to use conservation and decouple the growth of our economies from increases in water use. So I think that if we can do it at the municipal sector, there is a path forward for everyone on the river to figure out how to make it happen.
Elizabeth Koebele
It's so nice to have met you in person, Colby. Thanks for taking the time to join me on this episode of the Discover Science Podcast.
Colby Pellegrino
And thank you for having me.