Colby Pellegrino is the Deputy General Manager of Resources for the Southern Nevada Water Authority in Las Vegas, Nevada.
Las Vegas is the driest metropolitan area in the United States with an annual rainfall of just four inches.
We talked about the increasing population of Las Vegas, the unprecedented drought and the innovative water conservation programs the city has developed in the face of it all.
“Since 2002, our per capita water use has gone down 49%. Our total Colorado River use has dropped over 25%. At the same time, we added about 750,000 people to this valley. So, we added three quarters of a million people and we are using significantly less water.”

“You know, water conservation…we call it a journey, not a destination. But we are the driest state in the nation. And Las Vegas in particular, is the driest large metropolitan area in the United States. We get on average four inches of rain a year. The state gets on average nine inches of rain a year. And so as we look to what our options are to meet the needs of a growing community and a diversifying economy, we want to make sure we can control our own destiny. And the way that we can do that with the limited resources we have is through water conservation.
So we really stood up our conservation programs formally at the turn of the century, and we’ve just continued to build upon them since then, to where we sort of have this monster, kind of a three-headed Hydra of conservation programs, where we use code to make the necessary changes for how the community develops in the future. We have incentives and pricing, which we use to influence our existing customers. And then we have a really robust education and outreach component to make people aware of the other two legs of the stool, just remind people that we live in a desert.
Most people in Las Vegas are transplants. When I was born, 300,000 people lived here. Now, 2.3 million people live here. So the number of people that move here from somewhere else is striking, and we also have a very transient population. So you have people coming and going all the time from different climates and different regions, and they don’t necessarily think when they move in, “I’m in a desert and, and that should influence my lifestyle.”

“The water authority was originally created as Southern Nevada’s Colorado River use was rapidly growing. Our city’s populations were rapidly growing and there wasn’t a centralized voice to speak with the other states that shared the river. So the vision for the authority was originally based upon coming together and having one voice for Nevada in these negotiations, instead of having each municipality trying to get a little more from themselves at the expense of the greater good.
The community bought into that approach for how we dealt with the Colorado River and the other states. What that quickly transformed into was a way to be uniform in the conservation actions that we take, because where we have seen failure in other communities or disparity in other communities is where you have these different land use governing municipalities right next to one another.
So on one side of the street, you’re allowed to do this. And on the other side of the street, you’re not. That’s not what we thought Vegas needed to be successful. So we’ve sort of centralized the development of our conservation programs with the authority, as well as our future water resource planning and those kind of go hand in hand, the way we manage our demands has a really huge influence on how we meet the community’s future water resource needs.
We were rapidly growing our use of Colorado River water at the turn of the century at the same time that we were seeing this drought set in. 2000 is generally marked as the first year of this drought. 2002 is the driest year in recorded history on the Colorado River. And 2002 was also our peak water use year as a state from the Colorado River.
We actually used more than our allocation of Colorado River water. In 2002, we used about 325,000 acre feet of water. We’re allocated 300,000 acre feet. So I think that was the big wake up call that we had other resource options. We needed to bring them online, but we very quickly needed to change the way we were using water amidst this strikingly bad year of hydrology occurring on the river. And by 2004, we had sort of completely transformed from some passive conservation to some really active conservation efforts.
Since 2002, that being our peak year for water use if you measure it per capita, has gone down 49%. Our total Colorado River use has dropped over 25%. So in that year we used about 325,000 acre feet. Last year, we used 242,000 acre feet of Colorado River water. At the same time, we added about 750,000 people to this valley. So, added three quarter of a million people and using significantly less water.”

“The very first thing that really went into code, that is still one of the biggest successes we’ve had today, is limitations on turf installation.
If I could pause for a minute, the Las Vegas community is unique in that we get what’s called return flow credits. We sit very close to the edge of Lake Mead. We have a very new community, and that means everyone’s on centralized sewer. And so anything that hits a drain in this valley, that’s connected to centralized sewer, gets treated and returned back to the lake, and that does not count against our allocation.
So you could go to any hotel on the strip, turn on every shower, every sink, leave it on all day, and it would not impact how much water we get from the Colorado.
All of that indoor use is a closed loop. It’s getting captured. It’s going into the sewer system, it’s getting treated, it’s getting returned back to Lake Mead, so we don’t lose any of that water. It doesn’t count against our allocation. So we focus our conservation programs on what we call consumptive uses, by and large. The biggest consumptive use is landscaping.
With four inches of rain a year, there is nothing that grows in this valley, that’s not irrigated with potable water. I think that’s different for people that come from different areas. If you come from the high mountains in Denver, you have supplemental irrigation that you use, but your sprinkler system is not used regularly. If you’re from Kentucky, you probably don’t even have an irrigation system for your lawn. So that is where we focus our efforts.
So our first things that went into code were related to turf. Turf doesn’t belong on commercial properties. For residents, turf should be limited to the backyard only, and it should be 50% of your capable area. So let’s get rid of the wall to wall turf, and let’s be a little smarter about how we water. Turf in this valley uses about 73 gallons per square foot per year. Your average desert friendly landscaping uses about 18 gallons per square foot. So [there are] huge water savings associated with using desert friendly landscape instead of turf.
So those rules, 50% of the backyard coverage, nothing in the front yard, these are rules that are currently in place for new development. We’ve evolved that code even further throughout the years. So we have gone back and we’ve made further delineation of what a park is, because people were calling narrow strips of grass along the sidewalk, a linear park.
So we’ve made corrections like that and we’ve put in dimensions. If you’re going to have a park that has turf that people can actually recreate on, it should be at least 30 feet by 30 feet, or a minimum dimension of 30 feet in any direction. It shouldn’t have a huge slope associated with it. So we’ve progressively gone back in and made modifications. And actually just this year, our board passed a resolution that new development from today forward, should have no turf in single family residences. That the only places we should have living turf are schools, parks, and cemeteries.
AB 356 is a law that the Nevada state legislature passed in 2021. And what that required is that nonfunctional turf, which we loosely define as turf that has no recreational value, has to be removed from the valley, or you have to stop irrigating it by 2026.
Obviously we have people that are unhappy with it. By and large, we had much more support in the community for that than against it. We have been offering turf incentives in this community since 2000, but we really ramped that program up in 2004. We’ve increased those incentives throughout time. We have used various advertising and marketing strategies to get people to remove turf.
The legislation doesn’t include single family residences. So outside of single family residences, we estimate that there’s almost 4,000 acres of this turf, that’s just aesthetic, in the valley. Removing that turf would reduce our use by over 10%. So it’s a very important step for the community to take. And as conditions on the river got worse, it sort of came to the point where we said, “Why are we still asking people to do this? This is the point in time that we should be telling them.” And obviously, we had the legislator’s support. We had a unanimous vote in the Senate for a water bill, which I don’t think has happened in many, many, many, many years. That’s remarkable in the Nevada state Senate.
The biggest incentive program we have is cash for grass. We pay you $3 a square foot to remove your turf and put in desert friendly landscaping. That’s our biggest incentive program. We’ve removed over 200 million square feet of turf since the inception of the program. So, a huge conservation achievement for us associated with that. We have lots of other incentives. We have what we call water efficient technology, which is sort of a one size fits all approach for a business that wants to implement something that saves water. So, if somebody has an evaporative cooler that they wanna change to mechanical cooling, they can get a rebate from us. We incentivize converting your irrigation clock to a smart clock that you can control from your phone. And that will automatically delay for rain events or wind events. We also incentivize leak detection devices. We’re the first utility in the nation to do that. There’s a couple different type of products that either go in line on your water main or some of them strap directly to the meter. And those are designed to catch continuous flow and alert the customer sooner than we can otherwise, that a leak is occurring on site.
We have a water waste investigation team. Those are actually administered by municipality, and the Southern Nevada Water Authority provides some additional support layered on top. And what we’re mainly looking for there is outdoor water waste. So it’s people watering on the wrong day or at the wrong time of day. We have both day of week and time of day restrictions, depending upon the season. And water flowing off the property is a water waste violation. So you should be watering your grass, not the sidewalk. Leaks or other irrigation system malfunctions result in water waste.
We have so many different things. I would say the biggest is advertising related to getting people into our water smart landscape program and the advertising we do associated with those seasonal changes in watering schedules. So reminding people to get off the couch, go in their garage and reset their sprinklers, because the irrigation demands of your outdoor areas change significantly throughout the year. You don’t need to be watering in February the same as you are in August, and there’s significant water savings associated with that. We have all sorts of education and outreach that we do, including a speakers bureau. We have a whole youth education program. During the COVID era, we developed an online youth education program where teachers can check out videos and book a time for an expert to actually do a Q&A after they’ve watched some of the content. “

“One of the next big steps is leveraging technology. So as a community, we are transitioning all of our municipalities over to what we call advanced metering infrastructure, where instead of your water meter being read once a month, it’s being read instantaneously and that data’s being fed back to us. At the water district, which is about 70% of our customers, we’ve already implemented advanced meter reading. So we get hourly data from your meter instead of once a month data. That allows us to see if you have a leak better, because instead of just looking at your volume changing, we can actually see, oh, this house had continuous flow for 48 hours. That’s probably a leak.
So as that technology gets automated to where we’re getting that hourly, we’ll actually get to the point where we can send you a text message that says, “Hey, for the last three days, you’ve had continuous flow on your property, something’s wrong.” And then once the artificial intelligence associated with that advances, we’ll be able to see with much greater clarity, “Hey, your landscaping is using about twice as much this year as it was last year. Maybe you should check the run times associated with your irrigation system.”
We get a lot of other communities that reach out to us related to the things that we’re doing. And with a goal of being a global leader in this space, we’re out there actively sharing what we’re doing because we think these are things that make sense in a lot of communities. Water scarcity is one of the biggest impacts associated with climate change. So these are things that other people are looking at. Just with the passage of AB 356 to remove the nonfunctional turf, I don’t think I’d ever seen nonfunctional turf anywhere in water related news prior to that. And the California governor in his drought declaration a couple weeks ago said, “Nonfunctional turf.”
I think our staff has probably talked with half a dozen other cities, municipalities just in the first couple months that we implemented that to say, “Hey, what does this look like? How did you get there? This seems like something we should do.”
What continues to give me hope is that the seven states that manage the river are still able to come together and agree to do really hard things. One of the monikers of the Colorado River for a long time was [that it was] the most litigated river in the United States, because of the numerous trips to the Supreme Court related to the management of water. And that’s really changed since about the late nineties when folks kind of came together and said,”We’d have a lot more certainty if we can agree. And we may not all like what we agree to, but it’s going to create a lot more certainty than us fighting in court over our really staunch beliefs are about our rights.”
It’s not easy. But just two weeks ago, the secretary of interior sent a letter to the state saying I would like to reduce the amount of water being released from Lake Powell to Lake Mead, and the seven states, within the deadline she set, which was pretty short responded and said, “Yeah, we support this, and this is how we think this should be done.”
For all seven states to come together and agree to something like that is a sign that there’s still this collaborative nature and this desire to solve problems together. I think that’s going to be key for us managing some of what could be seen if these low end climate change projections for the river manifest themselves.
I think an idea that gets missed when we report on the latest agreement or the latest body showing up in a barrel, is really how many people the river impacts. 40 million people in the United States and Mexico rely on the river, millions of acres of irrigated agriculture, 29 federally recognized tribes, the largest national park units in the nation, all rely on the waters of the Colorado River. And I think when we talk about what needs to be done to meet the challenges of the future, the first place that most people go to is to find somebody else to blame for the problem.
We often get asked, “Well, why isn’t this city doing what you are doing? And what do you think about that?” I really think that collective awareness that all 40 million people need to do more to conserve water. All of the different users, whether you’re a municipality or a farmer or a rancher or a paddle boater…everybody needs to do what they can to save water because these challenges, we’re only seeing the tip of the iceberg, in terms of what climate change could really throw at us. So being resilient is going to take everyone’s collective effort.”
Discussion questions:
-Did you grow up in a desert landscape, or a different sort of climate?
-What are the landscape features you have grown familiar with? How water hungry are those plants?
-Does your community ever use lawn watering restrictions? How do you feel about that?
-At what point should a community tell people how and when to conserve, rather than ask them to?
-It seems we sometimes require a crisis before we find the collective will to act. Why do you think that is?
-In what ways do you consciously conserve water?
-Where do you have room to grow in your conservation ethic? What would be helpful in that effort?
She’s shero!
Very interesting! We in Southern Utah can learn a lot from what’s been accomplished in Southern Nevada. Our water officials like to assert that “return flow credit” is the reason their water use is so low. Our officials, meanwhile, have just passed water conservation ordinances that allow more grass than I had in my home twenty years ago before converting to xeriscape. That’s not moving in the right direction and not doing our citizens any favor as this water situation worsens.