Cloud-Seeding Efforts Aimed at Squeezing More Snow From Passing Storms
SALT LAKE CITY, Utah — For the first time since the 1990s, Salt Lake City is trying to make more snow than what nature has in mind.
The city has joined a long-running cloud-seeding effort aimed at squeezing more snow out of passing storms.
As meteorologist Stephanie Beall fired up a cloud-seeding device near the mouth of Big Cottonwood Canyon, she said it’s to “give Mother Nature a little something extra to work with in order to create more snowfall.”
Snow that falls in the Wasatch Mountains will be drinking water someday, and that’s why it benefits the city if cloud seeding makes more snow in the drainage above the Big Cottonwood Canyon water treatment plant.
Beall works for a company called North American Weather Consultants. She uses gear that looks a lot like the chimney starter on a charcoal grill. The “little something extra” is propane to make heat, which vaporizes a chemical mixture.
The heat launches a blast of silver iodide particles into the sky.
Just as she was getting started, Beall started to smile because the wind picked up and stiffened a flag that was fluttering on a nearby flagpole.
“It’s telling me that there’s colder air moving in,” Beall said, “and the seeding conditions are going to get better.”
As the snowstorm developed and moved east into the mountains, she seemed positively excited by the white stuff falling around her.
“The big flat flakes are the one’s we kind of like to see,” she laughed, “so, sorry. I’m a weather nerd. I can’t help it.”
When conditions are right, the burner goes for hours, day and night, pumping the silver iodide into the storm. Somewhere to the east the tiny particles become billions of little gathering points for moisture.
“They start to form ice crystals,” Beall said. “They form snowflakes. They get heavy. They fall. And then you have snow.”
If things go well, it creates more snow than might have fallen otherwise, according to Don Griffith, president of North American Weather Consultants. His company has a new contract this year with Salt Lake City.
“We call it the Six Creeks Program,” he said, “because what we’re trying to do is increase the snowpack in the six drainages that surround the Salt Lake Valley to the east.”
Snowbird and Alta ski resorts have paid for the cloud-seeding service for many years. But this is the first time in a quarter-century that Salt Lake City officials have figured it’s worth the money.
“You know, we’re the water provider for 350,000 people,” said Jesse Stewart, deputy director of Salt Lake City Public Utilities. “We’re looking at making sure we have a reliable source going forward.”
The city isn’t facing an immediate crisis, but a long-term drought has plagued much of Utah for the last two decades. City officials want to diversify their water sources to weather any future crises.
“Would we be fine without the cloud seeding? Probably,” Stewart said. “But we want to look at what can we do, just to give ourselves that buffer.”
State officials say studies show that cloud seeding really does boost the output of storms.
“The increase in precipitation is between a 5 and 15 percent increase,” said Candice Hasenyager, of the Utah Division of Water Resources.
In the view of state water planners, the effort is worth real money. Cloud seeding is far cheaper than building new dams and reservoirs because it produces water at $3 or less per acre-foot.
“If we went out and developed a brand-new project,” Hasenyager said, “you’re looking at a thousand dollars an acre-foot.”
The state this year is providing $300,000 in matching funds for local governments and water districts to pay for the cloud seeding. The practice has been going on in various parts of the state since a major drought in the early 1970s.
Over the years, some critics have questioned whether it’s a good idea to interfere with nature.
“Unnatural versus natural? I would say for the most part we’re just helping Mother Nature a little bit,” Beall said, “in a good way.”