Utah’s winter sports industry may claim the greatest snow on Earth, but for skiers and water watchers alike, there is hardly ever enough powder.
For nearly 50 years, the second-driest state in the nation has been giving natural winter storms an engineered boost to help deepen its snowpack through a program largely funded by state taxpayers, local governments and water conservancy districts. More recently, the states that rely on water from the lower Colorado River — California, Arizona and Nevada — have been paying for additional cloud seeding in Utah.
Thanks to the steady funding stream, Utah’s program has developed into one of the most comprehensive weather modification efforts in the West, and, after decades of expansion, every major mountain range in the state now sees extensive cloud seeding.
But that doesn’t mean aircraft are buzzing overhead, creating precipitation. Seeding — which in Utah is done mostly by stationary, propane-powered generators on the ground — is possible only under a narrow range of conditions, usually when snow is already in the forecast, explained Jake Serago, an engineer with the Utah Division of Water Resources.
Water particles hovering aloft as vapor in a cold-weather storm system need something to crystallize around to form snowflakes. In natural storms, each flake typically starts by bonding to a speck of dust or a bit of airborne salt.
“There is way more water in clouds than actually falls to the ground,” Serago said. “And that’s because there’s a limit on the number of particles that the water can freeze to.”
The goal of cloud seeding is to increase the number of particles in the storm and coax snow to fall in the mountains. According to the state’s estimates, roughly 7% of the snowflakes that land on Utah’s major mountain ranges any given winter freeze around tiny particles of silver iodide that are blasted into storm systems from more than 130 cloud seeding generators, mostly stationed along the western edge of the state’s mountains.
Cloud seeding to increase water supply
The program’s primary purpose is to up the amount of water in Utah’s rivers, and supporters say it’s one of the most cost-effective ways to boost runoff into the Colorado River Basin and the Great Salt Lake.
“I find it fascinating that we can give Mother Nature an assist and help augment the water supply,” said Kim Wells, a spokesperson for the Utah Division of Water Resources. “Traditionally, with water management, you do things by building dams or reservoirs or pipelines. But cloud seeding is different because it increases the water in a low-cost, low-risk, nonstructural way. So that’s a win for Utah — anything you can do to increase the water supply is a win.”
The state and its…