Modifying Weather: Cloud Seeding has Some New Believers

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ROCKY BARKER,
The Idaho Statesman

BOISE, Idaho—Cloud seeding once was seen similar to well divining, medicine shows and miracle healers.

But today Idaho Power Co. is investing up to $1 million to seed the clouds above Idaho's mountains, in hopes of increasing the snowpack that holds the water that will drive the hydroelectric turbines to produce the cheapest power the company can get.

The utility is not alone. Eastern Idaho counties and businesses have put together a coalition to pay for cloud seeding in the Upper Snake River Basin. They estimate their limited efforts already have increased the snowpack there by 7 percent, about half as much as Idaho Power hopes for.

"I feel really good about it," said Paul Romrell, a Fremont County commissioner who heads the coalition. "Our reservoirs levels are in better condition than they've been in for years."

The basic technology has been around for a while. Silver iodide is sprayed into the clouds, pulling the moisture out to form ice crystals that drop and fall on the earth as snow or rain.

Boise Airport has long used cloud seeding to clear winter fog that delays flights. Farmers experimented with the technology back in the 1980s.

Venezuelan President Hugo Chavez made news recently when he called for a massive cloud seeding program to combat the record drought in his country and Cuba. China has the most extensive weather modification program in the world, with more than 35,000 people working in cloud seeding programs across the country, Business Week reports.

In the past, cloud seeding's effectiveness for increasing precipitation was dismissed except in special cases, said Kevin Wade, Idaho Power water resource information supervisor. But scientists recognized that it was effective when it was used in mountain ranges to create snow.

That has led several Western states, including Wyoming, Nevada and Colorado, to embark on major cloud seeding efforts. Idaho Power began in 2003 after a stockholder at an annual meeting asked its leaders to study it.

Roger Fuhrman, who headed Idaho Power's water management staff, was skeptical, but the utility put engineers CH2M Hill to work on the study.

"They convinced us this was real science and could be duplicated," Fuhrman said.

Now Idaho Power has 10 silver iodide generators on the ground in the Payette drainage and one plane devoted to cloud seeding there. It has another 10 of the remote-controlled generators in eastern Idaho, where the coalition has 25 manually operated generators.

"The remote control generators can be fired up from a laptop in Boise," Romrell said.

The company estimates it can increase the snowpack in the watershed above its hydro dams from 120,000 acre-feet to 250,000 acre-feet annually. That means the $1 million expenditure breaks down to about $7.70 an acre-foot.

"That varies from year to year," Fuhrman said.

For comparison, Idaho Power pays $8 an acre-foot to buy power in the Payette Basin and more than $20 to buy water in the Upper Snake.

The technology is not without a downside. When a huge blizzard brought record snows this month to Beijing and other cities, Chinese officials acknowledged that cloud seeding contributed. The state-run Xinhua news agency said the Beijing Weather Modification Office claimed it had created 16 million metric tons of additional snow in the storm, which angered people caught in it.

Idaho Power and eastern Idaho officials say the cloud seeding they do is targeted to backcountry drainages in the Payette Basin and eastern Idaho.

"If the wind would put the snow over a populated area, we won't turn it on," Romrell said.

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