PHOENIX â Drought-plagued Arizona could see state-funded drones spraying microscopic silver iodide particles into mountain clouds to boost snowfall if proponents get their way.
The state Legislature is considering allowing the use of money earmarked for boosting rural water supplies to pay for "cloud seeding'' operations to increase precipitation in the state's high country.
But the proposal sponsored by Rep. Gail Griffin, R-Hereford, may have a tough road ahead.
That's because even some majority Republicans on the committee that heard her proposal expressed concern about the safety and efficacy of cloud seeding. It passed Griffin's committee on Jan. 13 with a bare majority.
And some Republicans have been pushing bills in recent sessions that would ban any weather modification efforts, although they're mainly focused on theoretical proposals to lower global temperatures by partially blocking sunlight.
One bill introduced this year would specifically ban releasing any chemical into the atmosphere with the intent of affecting temperatures, climate, weather or sunlight intensity. But Sen. John Kavanagh, R-Fountain Hills, told Capitol Media Services that he plans to amend his proposal to exempt cloud-seeding under current state licensing rules.
Cloud seeding involves spraying microscopic particles, usually silver iodide, into clouds to boost rain or snowfall. Arizona law requires any effort to modify the weather or artificially increase rainfall to be licensed by the Arizona Department of Water Resources.
The new proposal, HB 2024, would allow the Water Infrastructure Finance Authority to tap one of its funds to pay for cloud seeding by reclassifying snowpack augmentation as a qualifying water supply development project.
The agency known as WIFA is best known for its expanded role of finding new water supplies to import into Arizona. But it has a longstanding mission of financing and backing new rural water supplies, funding drinking water supply and wastewater infrastructure projects and backing conservation efforts across the state.
Griffin focuses on water legislation as chair of the House Natural Resources, Energy and Water Committee. She called cloud seeding "another tool in the toolbox'' for boosting Arizona's water supply.
Rep. Gail Griffin, R-Hereford, is sponsoring a bill that would allow the use of money earmarked for boosting rural water supplies to pay for "cloud seeding'' operations.
Backing the effort is an El Segundo, Calif., startup company called Rainmaker Technologies Corp. that is already doing cloud seeding operations in Utah and Idaho with funding from those states. The company is using drones and ground-based generators to inject silver iodide particles into clouds when conditions are ripe.
In the decades-old technology, the particles help ice crystals form and can increase rainfall or snowfall.
Rainmaker has multimillion-dollar contracts with those states to boost snowfall in the Bear River Basin, a 7,600 square mile watershed located in Utah, Idaho and a slice of western Wyoming. The basin is drained by the 350-mile-long Bear River, which is widely used to support the region's farms and empties into the Great Salt Lake.
Shawn Martini, who handles the company's government affairs, testified that the company operates in seven states and that the Bear River operation is one of the largest in the nation's history.
"At Rainmaker, we spend a lot of time thinking about water and how the conversation and mindset is always one of scarcity and doing less with less,'' he told the committee. "And hopefully with the application of this technology, we can shift the conversation and the mindset from one of scarcity to one of abundance and at a minimum additionality.''
He said the company's use of drones to fly into promising cloud formations identified using radar is what sets it apart, making its cloud-seeding operations more precise and efficient.
"The difference with what Rainmaker technology does, as opposed to other cloud seeding operations that have historically operated across the West, is we deploy the aerosol silver iodide into the cloud using drones so that we can be as targeted and efficient with those operations as possible to make as much water as possible, at the lowest cost,'' Martini said.
If the legislation is approved and signed by Democratic Gov. Katie Hobbs, Rainmaker Technologies won't be able to tap into the funds unless it partners with a "water provider'' as defined by WIFA, agency spokesman Ben Alteneder said. Rainmaker representatives approached WIFA to inquire about funding, but were told they didn't qualify because they are not a water provider.
Martini said in an interview that his company does not yet have an agreement with a water provider for any snowmaking operations.
Judah Waxelbaum, chief of government affairs for WIFA, told Griffin's committee that the changes her bill makes would allow a water provider to tap into the Water Supply Development Revolving Fund, which funds projects outside of the Phoenix, Tucson and Pinal County areas.
Known among water purveyors as the "rural fund,'' the Legislature appropriated $200 million for the long-dormant fund in 2022 when it also remade the agency's mission into one that also seeks new out-of-state water supplies. WIFA's board has approved spending $85 million of that so far. The fund offers grants up to $2 million and loans up to $3 million, and its rules mandate that 60% of the money is loaned.
The proposal approved by Griffin's committee only advanced because one Republican committee member, who was concerned about "manipulating the weather," changed her vote to yes at the last minute.
Rep. Pamela Carter, R-Scottsdale, initially voted against the measure but then changed her vote and allowed it to advance to the full House.
"I really want more research on the whole messing with our weather. I'm not a fan of it, and I just think we have a lot of that going on, and I'm concerned," Carter said. "So? I'll change my vote to run it through committee today, but reserve my right to say no on the floor.''
All four Democrats on the 10-member House committee opposed the measure.
In all, nine Western states currently do cloud seeding, according to the North American Weather Modification Council, which helps coordinate the efforts.
Arizona currently has no active cloud seeding operations, although the Pinal County Water Augmentation Authority ran a test last summer where an airplane sprayed silver iodide crystals into clouds.
The Salt River Project also participated in a cloud seeding climatology study several years ago, although no actual cloud seeding was done.
The study, where SRP collaborated with the Desert Research Institute in Reno, NV., was conducted between 2020 and 2023 and designed to use weather modeling and actual observations to determine how often conditions in eastern Arizona were ripe for cloud seeding to actually work, according to SRP and the Department of Water Resources. Measurements are ongoing to determine how well the study measured actual winter weather in the area, according to SRP.
SRP hasn't discussed doing actual cloud seeding, spokesperson Elaina Steingard said in an email. The water and power provider is first working to determine if it would be worthwhile.
The Central Arizona Project, which runs the canal that feeds Colorado River water to Phoenix and Tucson, currently helps fund cloud seeding operations in Wyoming, Colorado, and Utah. Also participating in that operation are Nevada and California water agencies.
In Pinal County last year, aircraft conducted 30 flights between July and September in an effort to determine if cloud seeding could boost summer monsoon rains, with a meteorologist using radar data to determine target dates and locations.
The final report prepared by the meteorologist who oversaw the project called it "a good start and a success.''
"Clouds seeded yielded an increase of 0.47 inches across the target area, resulting in 134,192 (acre-feet) of water production,'' meteorologist Bria DeCarlo wrote in the report, "This water led to numerous benefits across the region.''
The effort was done by Seeding Operations and Atmospheric Research, known as SOAR. DeCarlo is identified as a state-licensed meteorologist with the Texas Weather Modification Association â and she also works for Rainmaker Technologies. Weather modification is often used in place of the term cloud seeding.
The Pinal County effort drew the ire of Rep. Teresa Martinez, R-Casa Grande, who said she only learned about the project after the fact.
"I'm notified all the time, with lots of stuff that's going on, but not once was I notified,'' she said during a hearing about the local cloud seeding project. "And so I am insulted and offended still that Pinal County would not notify me to loop me in.''
Martinez sits on Griffin's committee and voted to advance her cloud seeding funding bill, but that doesn't necessarily mean she supports it. Far from it. But she said there's nuance to her position.
"I am afraid of it, and I said that, and I even used an analogy about new technology. I'm still afraid,'' she said. "I need to learn more about the chemicals that they're shooting up into our atmosphere.
"And I, to this day, I'm still afraid of this technology, but I understand that it is new technology,'' Martinez said. "What I'm not ready to do, and this is the difference, I'm not ready to stop having the conversation about it. And a 'no' vote would mean we're stopping the conversation. And that's the nuance.''
She said she may end up actually supporting cloud seeding, but she needs to learn more about it.
"Any person can change their mind,'' she said. "And I think that it is a sign of reflection and really earnestly listening to both sides.''
Whether cloud seeding is actually effective is not certain, as a 2024 report from the Government Accountability Office found. States are split over whether to embrace it, with nine states currently using it while ten others have either banned it or have considered banning cloud seeding or weather modification in general.
And while it may increase water availability and lead to economic and other benefits, the GAO report said scientific studies are limited and show a broad range of results, with increases in precipitation ranging from zero to 20 percent. The studies reviewed on the use of silver iodide show it doesn't pose environmental or health concerns at current levels, but it isn't known if more widespread use could have negative effects.
Testifying against Griffin's bill was Sandy Bahr, director of the Sierra Club's Grand Canyon Chapter. She said there are questions about whether silver iodide accumulates in the body and that the actual effectiveness of cloud seeding is in doubt.
"There's a lot of uncertainty associated with it,'' Bahr said. "Cloud seeding has shown itself to be quite inconsistent. There are also a lot of unintended consequences associated with cloud seeding.''
Besides Reps. Carter and Martinez, who both voted yes but expressed reservations, the other Republicans on Griffin's committee supported the measure. One was Rep. James Taylor, who noted that the Environmental Protection Agency regulates and limits the use of silver iodide, and businesses like Rainmaker Technologies stay within those limits.
"I think with anything new, there's a certain apprehension, reluctance to endorse that and embrace it and put it in service. That's human nature,'' said Taylor, R- Litchfield Park. "But I think that we had some good concerns that were expressed from our witnesses, and I think that it all boils down to the EPA has limits on this, and (businesses)? they stay within those limits.''
Rep. Ralph Heap, R-Mesa, said he was encouraged that Rainmaker's use of drones could reap better benefits, and he's not concerned about the use of silver iodide. But he, too, said he needs to do more research before the whole House takes up the measure.
"Cloud seeding is definitely not, from what I can tell, a silver bullet for the problem,'' Heap said, with mixed results over the past 50 years.
"I am encouraged by the drone idea,'' Heap said. "I think that that could have benefits that we haven't really been able to get with the normal way of cloud seeding.''
Democratic Rep. Mae Peshlakai, a member of the Navajo Nation from Cameron, said she's wary of artificial cloud seeding.
"I'm really quite confused about artificially producing any type of moisture with (these) kind of chemicals,'' Peshlakai said while explaining her 'no' vote. "But just to let you know, I trust the traditional rain dance more than I would this type of thing.''
