People wade in the shallow waters of the Virgin River in St. George, Utah. The river provides the desert community with water, but climate change and a growing population threaten that supply. Local leaders are looking toward recycled sewage as a solution.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
Climate change shapes where and how we live. That’s why NPR is dedicating a week to stories about solutions for building and living on a hotter planet.
ST. GEORGE, Utah — Water scarcity, population growth and climate change are on a collision course in the American West.
That’s clear in cities like St. George, a desert community surrounded by stunning red rock cliffs and mesas in Utah’s southwest corner. The population is booming and climate change is making heat more intense and rain less reliable. But local leaders have a plan to stretch the area’s water supply by turning to its sewage — a solution that could help other drought-stricken cities, too.
That plan started with a simple math problem.
“All the water has been used. It’s been called for. But yet, we have one of the fastest-growing communities in the Western United States,” said Zach Renstrom, general manager of the Washington County Water Conservancy District in St. George.
Washington County has one of the nation’s fastest-growing populations in recent years. “We’re looking at hundreds of thousands of people moving to our community, and we have no extra water for them,” said Zach Renstrom of the Washington County Water Conservancy District. The county expects that reusing its wastewater will provide more than half of the additional water it will need to sustain growth into the 2040s.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
“So, we’re looking at hundreds of thousands of people moving to our community,” said Renstrom, “and we have no extra water for them.”
As recently as 2021, this sun-drenched outdoor recreation hub was the fastest-growing metro area in the U.S. The local population, now just over 200,000, has more than doubled since 2002. The University of Utah projects it could double again by 2050.
That’s where the sewage plan comes in.
“If you want to know the true value of water, that occurs when the well goes dry,” Zach Renstrom said. Despite the high price tag of building wastewater recycling plants, smaller communities like St. George believe it may be the best way to sustain their water supplies into a hotter, drier future.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
At a construction site just east of St. George, Renstrom walked toward a maze of rebar and concrete that’s slated to become a new wastewater reclamation plant by the end of 2025. Once complete, it’ll take effluent from local kitchens and bathrooms and clean it with screens, bacteria and UV light.
In the near term, the treated wastewater will be sprayed on lawns and farm fields. But that will free up water for homes, too, because the county currently uses some of its drinking water for outdoor irrigation. Within two decades, Renstrom expects the district will start sending the clean water from its reclamation plants directly into the drinking supply.
Reusing water that would have otherwise flowed downstream to Lake Mead — the nation’s largest reservoir — is the centerpiece of the district’s long-term water plan. But it will come at a steep cost: over a billion dollars.
“Traditionally, I would say that you would have to be a very large, large, large municipality to be able to afford that massive infrastructure,” Renstrom said. “But now we’re getting to the point where, even small communities like us, it’s our only option.”
Golfers play a round on the manicured landscape of a Washington County golf course. In this desert climate, irrigated grass can be a significant strain on the local water supply. That’s why the county has introduced incentives and regulations in an effort to increase water conservation.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
The tall task facing cities in the West
St. George’s quandary is a microcosm of the challenges cities face across the Western U.S. as overuse and drought strain the Colorado River and the basin’s seven states fight over how the river’s water gets distributed in the future.
Expanding wastewater reuse operations regionwide could go a long way toward easing that pressure, said UCLA water researcher Noah Garrison. There just needs to be a lot more of it.
“One of the reasons why we need to be investing in wastewater recycling now is that this isn’t some hypothetical future concern we’re dealing with,” Garrison said. “We already are seeing water scarcity and water stress in all of these regions, and developing out wastewater recycling does take time.”
While other places like Los Angeles, Phoenix and San Francisco recycle a lot of their sewage already, Utah reuses less than 1% of its wastewater statewide. A recent analysis Garrison co-wrote suggested that if all basin states start reusing more than half of their wastewater — as Nevada and Arizona already do — it could make up for around a third of the region’s expected water shortfall.
A visit to St. George’s main water source, the Virgin River, highlights the urgency.
This waterway carved the towering red rock canyon in nearby Zion National Park. But after a historically dry winter, the section snaking through St. George has become shallow enough to walk across without getting more than your ankles wet.
“This is it,” district conservation manager Doug Bennett said as he motioned toward the meager flow. “This is the lifeblood of the entire region.”
Before reaching the residents of St. George, the Virgin River runs through Zion National Park, attracting diverse wildlife and millions of tourists each year.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
In addition to reusing water, St. George and neighboring communities have adopted conservation rules in recent years that nearly eliminate grass on new development. The district also pays residents up to $2 per square foot to rip out their irrigated lawns — a strategy other cities from Denver to Fresno to Spokane have tested, too.
The southwest Utah program has incentivized homeowners and businesses to remove more than 2 million square feet of grass since launching in late 2022. But Bennett knows it has a lot of room left to grow, especially among local golf courses. That’s where the region’s record dry conditions this year could help.
St. George and surrounding communities recently passed regulations that limit grass lawns around new housing. Changing the region’s mindset about water conservation may present a challenge, but successful examples from Las Vegas and elsewhere offer hope. “It proves what can be done and that it is doable,” Doug Bennett said. “You just need to get people mobilized behind the effort.”
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
“One of the biggest threats to implementing all these programs is complacency,” Bennett said. “A drought can be a big motivator for people to say, ‘What can I do to help?'”
Making growth sustainable in a dry, hot, booming place like St. George may be a tall task, but Bennett believes it can work. He saw it in his previous job at the water district in Las Vegas.
The Virgin River is where the St. George area gets its water for drinking and irrigation. It’s also a hub for outdoor recreation. Here, people cool off at the Virgin River Skimboard Park.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
Bigger cities are proving the water-saving tech
Just 120 miles to the southwest, Las Vegas is St. George’s glitzy neighbor, and it has been reusing wastewater on a large scale for decades.
At the Clark County Water Reclamation District’s main plant, Strategic Services Manager Bud Cranor creaked open a tall, metal door. Behind it flowed some of the 100 million gallons of sewage this plant treats each day.
“Right here is all the poop from every casino, every business,” Cranor said. “It’s like every little 12-year-old boy’s dream is working at this place, because you get to make poop jokes all day.”
But for a city in the desert, it’s no laughing matter.
“What we do here is absolutely vital to this valley’s survival,” he said.
Squeezing clean water from this sea of sludge has helped the Vegas metro population more than double in the past two decades. It now has nearly 2.4 million people. Conservation efforts have played a big role there, too. Even as Vegas welcomed hundreds of thousands of new residents, the area decreased its total water consumption — a concept known as decoupling.
As more communities work to ensure their residents have water for the future, Cranor believes what Vegas has accomplished can be a neon-glowing case study.
“That will become more and more of a priority as it becomes a scarcer resource,” he said. “So cities, if they’re not already thinking about it, they’re going to have to start thinking about it more.”
The Clark County Water Reclamation District’s main plant in Las Vegas, Nevada, treats over 100 million gallons of sewage every day. It then releases clean water into the Las Vegas Wash, which flows to Lake Mead. “This is the result of a lot of human ingenuity and creativity,” Bud Cranor said, “to figure out how to clean and treat this finite resource so that it can be reused and it can help people survive.”
Top: Clark County Water Reclamation District Bottom: Ryan Kellman/NPR
hide caption
toggle caption
Top: Clark County Water Reclamation District Bottom: Ryan Kellman/NPR
What it might take to grow in the future
Now that Las Vegas, Los Angeles and other major cities have proven the concept of wastewater reuse, Newsha Ajami has seen a growing trend of smaller communities following their lead. She’s a water researcher with Stanford University and the Lawrence Berkeley National Laboratory.
When it comes to scaling up reuse, Ajami said the technology is not the main limiting factor. Rather, “it’s often a policy problem or sort of governance structure that needs to change to embrace some of these solutions.”
Cities may face their own localized challenges, too. In St. George, one of the limiting factors is the need to build additional reservoirs that can store the water its reuse plants clean. Las Vegas sends its recycled water into massive Lake Mead, which is well under half-full as Western megadrought and overuse shrink large reservoirs across the West.
St. George homeowner Karen Goodfellow works on her backyard project to replace grass with water-efficient plants. The county hopes its program that pays residents to remove irrigated lawns will encourage more people to do the same.
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
Ultimately, Ajami said the extent to which wastewater reuse can allow a city to grow is up to its leaders, its budget and its willingness to adapt. For some communities, that may mean prioritizing pricey water infrastructure updates. She also envisions a future where reuse becomes decentralized, like a neighborhood having its own microplant or even in-home systems.
“You can do it smart,” she said. “For example, if you build new buildings, new homes, and say, ‘OK, you know what? You’re going to connect the shower water to toilets.'”
Ajami compares it to the adoption of solar panels on home roofs in recent years. As those become more common, they help a city reduce the pressure on its power grid. Expanding decentralized reuse could potentially do something comparable for a city’s water supply.
“That is definitely the future,” Ajami said. “It might not be here now, but in the next 10-15 years, I can see more and more of that happening.”
The wastewater treatment plant being built near St. George is a sign of the changing times, too.
When Renstrom studied water management in engineering school 25 years ago, he said the biggest question about sewage was how to get rid of it.
“In my career, that has completely changed,” Renstrom said, “where now, people are fighting over this.”
Communities like his are counting on that sewage to sustain them into a hotter, drier future.
In St. George and across the Southwest, climate change is making extreme heat more intense and rainfall less reliable. The people in charge of managing local water supplies are taking note. “Anybody here in the West that is not thinking about that, they’re missing it,” Renstrom said. “Because we have to build an infrastructure now that’s very adaptable to whatever happens.”
Ryan Kellman/NPR
hide caption
toggle caption
Ryan Kellman/NPR
