Humans have the technology to literally make snow fall from the clouds. In the drought-stricken Southwest, where the Colorado River needs every drop of water it can get, there are calls to use it more.
Utah, home to the nation's largest cloud seeding program, is at the crossroads of the technology's past and future. The state has become a proving ground for cloud seeding in the West, with water managers, private sector investors, and conspiracy theorists keeping a close eye on their progress. Advocates say the technology works, and now they need to figure out exactly how much.
For a practice that has launched millions of dollars in funding, countless snowflakes and a string of death threats, the technology itself is strikingly uncomplicated.
On an overcast day in the foothills near Ogden, Utah, Jared Smith crunched through a thin layer of spring snow toward a white trailer about the size of a dumpster. Inside, he explained, is a solar-charged battery, a tank of the non-toxic chemical compound silver iodide, a tank of propane, and a few valves and switches that control their flow.
"Most complicated things are just a lot of simple things put together," Smith said.
He works for North American Weather Consultants. The company is based in the Salt Lake City area and operates about 200 of these setups across Utah.
With one click of a button, the machine whooshes to life. A small orange flame flickers from the tip of a shiny pipe atop the trailer as tiny particles of silver iodide, invisible to the naked eye, drift off into the sky.
That's pretty much it.
From here, those particles drift into passing clouds and cause ice crystals to form. That process, Smith says, is like those videos of people who put bottles of water in the freezer. When they pull them out, the water is below freezing but still liquid. With a quick whack against a hard surface, it quickly turns to ice.
Cloud seeding takes below-freezing water inside a cloud and gives it a silver iodide particle to grip onto, at which point it hardens, turns into a snowflake, and falls to the ground.
One thing cloud seeding does not do, Smith said, is create snow out of thin air. It only works when there are already water-laden clouds in the sky.
"If we could create the weather," Smith said. "I'd probably be retired, owning an island in the Bahamas."
Tweaking the tech
While the concept of cloud seeding can sound like the stuff of a distant sci-fi future, the technology has been in use since the 1950s. And since then, it has gone largely unchanged.
In Utah, though, North American Weather Consultants and its parent company are tweaking the way the machines are used, and hoping to blaze a new trail towards more efficient and precise cloud seeding. They're doing that in two ways.
For years, if you wanted to turn on one of those silver-iodide-spouting machines, you had to do it in person. That's not always an easy task, since they're often placed where they'll be the most effective – in remote mountain ranges buried under deep snow.
Now, they can be turned on from a phone, anywhere in the world.
Instead of asking a person to drive, trudge, or snowmobile to a faraway generator – often hours before a storm starts in the wee hours of the morning – they can be turned on from a technician's home on the other side of the state at exactly the right moment. That means less propane and silver iodide are wasted and the machines can spend more of the winter fully operational.
"You're able to operate in the middle of the night, turn it on for an hour, turn it off without bothering anybody," Smith said.
So far, North American Weather Consultants has switched about 100 of its roughly 200 generators to remote operation, and plans to upgrade the remainder over the next few years.
The company is also testing a new way of getting silver iodide particles into clouds with drones. While they're still awaiting permits to use them fully, the company plans to take those particles straight to the source by flying drones that can disperse the compound straight into the clouds.
Measuring the impact
Utah's cloud seeding program is being closely watched by others around the region. Its efforts cover more ground than any other state in the nation, and it has one of the strongest bases of state funding.
For that reason, other water-short states in the Western U.S. are keeping an eye on how much return on investment Utah is getting from a $5 million annual cloud seeding budget and those efficiency-boosting tech upgrades.
Jonathan Jennings, who runs the cloud seeding program at the Utah Department of Natural Resources, said between the new tech, the funding, and backing from the state's legislature, "Utah is climbing its way to one of the best programs in the world."
"It's a lot of pressure," he said, "Because I do realize that our neighboring states are watching how we spend our money and what comes out of it."
What has come out of it, so far, is an amount of snow that would raise the eyebrows of most water managers in states gripped by drought and steady demand. Utah says it is able to boost its snowpack by 6-12% each year through cloud seeding. For states that depend on the Colorado River, about 85% of which begins as mountain snow, that is significant.
"If you're able to continue to live in the state of Utah without any worry about water," Jennings said, "That's part of the cloud seeding program helping."
Beyond cloud seeding's ability to create water, it's generating buzz because of its ability to do so cheaply.
As policymakers try to rein in the Colorado River's supply-demand imbalance, they're considering myriad ways to add more water or cut back on use. Water conservation is often the most cost-effective way to do that, and the reason that governments have spent hundreds of millions on programs that pay farmers to use less.
When it comes to adding to the supply, cloud seeding is less expensive than other trendy water technologies like desalination and wastewater recycling. A 2018 study of Utah's program found that cloud seeding could create an acre-foot of water for less than $3. The Colorado River basin's largest desalination plant, by comparison, produces the same amount of water for more than $3,000.
"If we have a really good return on investment," Jennings said, "Other states can look at that and say, 'Wow, we're under-funding our cloud seeding program, we need to do this.'"
Investment from out of state
The Colorado River supplies about 40 million people from Wyoming to Mexico. Its water flows to kitchen faucets in cities like Denver, Phoenix, Salt Lake City and their growing suburbs. It supplies a multibillion-dollar agricultural economy that puts produce on supermarket shelves across the nation. But the river is in the grips of a climate change-fueled megadrought going back longer than two decades, and its supplies are dwindling.
Any technology that can add more water to that stretched-thin system is going to turn heads. It's the reason that the main water distributor in and around Los Angeles is pouring billions into a system to turn sewage directly into drinking water.
It's also the reason that relatively faraway water agencies are investing in Utah's cloud seeding program in hopes it could help them — both in the future and today.
The Colorado River's Lower Basin states of California, Arizona, and Nevada send about $1.5 million each year to Utah, Wyoming and Colorado for cloud seeding work, one-third of which goes to Utah.
The Southern Nevada Water Authority, the main supplier for Las Vegas and its suburbs, sent $800,000 to Utah's cloud seeding program to purchase equipment. Southern Nevada gets about 90% of its supply from Lake Mead, the nation's largest reservoir, which is primarily filled with melted snow from Utah, Wyoming, Colorado, and New Mexico.
The Las Vegas area is a poster child for water conservation. It has spent big money on efficiency programs, making its financial involvement in Utah's cloud seeding work look like a valuable stamp of approval.
Colby Pellegrino, the Southern Nevada Water Authority's deputy general manager of resources, said cloud seeding is unlikely to end the Western water crisis alone.
"I think it's one arrow in the quiver, one piece of the silver buckshot," she said. "But it's not going to be the thing that saves us all. We've seen enough studies to believe that the costs are low and the benefit we get is enough that it's worthwhile for us to do."
At the same time, the private sector is starting to see the value in cloud seeding too. A California-based startup called Rainmaker recently acquired North American Weather Consultants. Augustus Doricko, the company's founder, pointed to a 2017 study called SNOWIE that helped prove cloud seeding's efficacy, and said the industry has been ripe for expansion since then.
"I think someone just had to do it," he said. "I think that this technology has been perceived wrongfully as third wheel crack quackery for decades, and even in the last eight years since SNOWIE, the research community has been spectacular in driving the ball down the field on innovation."
Doricko said remote-operated cloud seeding generators have brought down cloud seeding's logistical complexity by an order of magnitude, and represent a "huge, huge step in the right direction."
Conspiracy theories and death threats
For all of the positive energy around cloud seeding and its future, a small group of detractors is making life difficult for the technology's biggest proponents. And this year, it got personal.
Some conspiracy theorists associate cloud seeding with the idea of "chemtrails." It's a theory that the government is spraying mysterious substances into the air in order to, among other things, control the minds of the people living below. The theory started percolating through internet forums in the 1990s, often concerned with the harmless streaks of water-based vapor and exhaust left behind by large airplanes.
The theory extends to cloud seeding programs and still has ardent believers in 2025. Just ask Jonathan Jennings.
Earlier this year, his personal social media was "completely overrun by fanatics." They harassed him, publicized his home address and even sent death threats.
"They took it a step too far," Jennings said.
The attacks also extended to other employees of the Utah Department of Natural Resources, including some who had nothing to do with the state's cloud seeding program.
The harassment left Jennings frustrated not only because of the personal attacks, but because he has been working on cloud seeding for decades and knows the technology and silver iodide are safe.
"I live here," he said, "My family lives here. All of my friends live here. If we were truly doing something nefarious, I'd be the first to stop that."
Jennings does not seem deterred by the attacks, and quoted longtime cloud seeding operator Don Griffith in expressing his commitment to staying the course.
"Once you get silver iodide in your blood, it's hard to get it out," Jennings said. "This is a lifelong passion now."
'Let's put some real science and money behind this'
Utah's cloud seeding program and the state government's willingness to fund it, is the envy of its neighbors. In Colorado, where the cloud seeding program operates on a substantially smaller annual budget, the state's cloud seeding officials are looking to expand.
"There's always advancements to make," said Andrew Rickert, who manages Colorado's weather modification programs. "I wish we had more funding to throw behind this."
Rickert said he sees promise in drone programs like the one Utah is piloting. They could make a significant difference in Colorado, where more than two-thirds of the Colorado River starts as snow.
"Let's put some real science and money behind this and show people that we can increase our water in a safe and efficient manner," he said.
In the meantime, Utah is pressing forward.
"Everybody not only has eyes on Utah," Jennings said, "But they support what we're doing in hopes that we are widely successful to the point where their states are going to be forced to fund cloud seeding even more than they are."
This story is part of ongoing coverage of the Colorado River, produced by KUNC in Colorado and supported by the Walton Family Foundation. KUNC is solely responsible for its editorial coverage.
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