BOISE, Idaho — In much of Idaho and parts of Oregon and Washington, you’ll find vast areas of dry arid desert. Water is the necessary component for life.
“We depend on water for irrigation, for our farmland, we depend on water for of course our own drinking needs, we depend on water for recreation which is a big part of our economy here in the West,” says Tim Merrick with the U.S. Geological Survey.
Watch the video from a report that aired Feb. 8 on Idaho Reports:
It irrigates crops, flows from our faucets, and provides for recreation, fish and wildlife. And it powers the Pacific Northwest as it tumbles through giant hydroelectric dams.
But where does all this water come from? Some of it comes from rain in the the spring, summer and fall. Some comes from underground aquifers.
A lot of the water originates in the mountains. The winter snow high on the mountain peaks in central Idaho and western Wyoming melt during the warm summer months and finds it way to the Salmon, Boise and Clearwater rivers - eventually flowing into the Snake River and heading west.
For nearly a century, Westerners have looked for ways to help increase the water they have. One way is through controversial method of cloud-seeding.
The goal of this decades-old process is to increase the amount of rain or snowfall when a storm moves through an area. But even today there are questions over how effective it really is. EarthFix caught up with a team at Idaho Power who are convinced cloud-seeding does work and have adopted it to increase snowpack in the mountains as a way to bank water that can power hydroelectrical turbines in the summer and fall.
Derek Blestrud is a meteorologist, one of four hired by Idaho Power to help forecast when a snow storm is approaching. Blestrud says “when you look at cloud seeding, it’s a water management tool. It’s not something that we use to eliminate a drought. You can enhance what’s falling naturally.”
The utility pays for and operates two cloud seeding programs in Idaho. One in central Idaho and another in eastern Idaho. There are 36 cloud seeding towers. Blestrud and a field engineer are one such tower near Idaho City about forty minutes northeast of Boise.
Brandal Glenn is the lead field engineer. He describes what the tower looks like: “What we are looking at is essentially a 26-foot tower with a lattice structure with a burn head.”
The flame is burning a unique blend of propane mixed with silver iodide. The heat causes the silver iodide to rise into the air and into a passing storm system. It then bonds with water particles too light to fall as snow. As water particles gather on the silver iodide - it gains enough weight to fall to the ground.
You can drop silver iodide out of an airplane or fire it into the air by cannon. But Idaho Power decided use these towers instead. Building them on lower-elevation mountain peaks. This is where you find “orographic lift” — rising air that charges up a mountain range. The quick rise in elevation causes the air temperature to drop and raises the relative humidity. This is where a storm is likely — and where Idaho Power wants the snow to fall.
“If you think of orographic lift,” says Blestrud, “there is not much happening in say Boise itself. Thats all happening when the winds hit the mountains and lifts up and over. Thats beyond Boise, thats back in the mountains, back in the Boise basin and the Payette. So we are starting to target that portion of it.”
Idaho Power’s cloud-seeding tower is powered by a small solar panel, providing enough power to run a satellite modem. That’s so meteorologists can turn it on and off from the Idaho Power building in downtown Boise.
“We measure temperature and humidity at this site. At some sites we have temperature, humidity and winds…and pressure,” says Idaho Power’s Brandel Glenn.
Idaho Power is seeding clouds as part of its strategy to make sure there’s enough runoff from melting snow in the summertime. That translates into water in rivers — and more water means more power generated from those rivers’ hydroelectric dams.
Greg Clark, a hydrologist with the USGS, says: “when you start looking at Western water and how valuable it is and water rights. Every cubic foot of water is valuable.”
The USGS measures the amount of snowmelt every year. We found him and several colleagues at a 101-year old river gauge on the Boise River. The reason its important to measure river flow is to determine how much water to expect for agriculture, reservoirs and even recreation.
Clark says “every drop of water, I don’t want to say has a purpose but it is utilized in some way whether it be by the environment or whether it be by humans. It is used in some way and is a very critical part of the whole.”
Over the years - Clark has noticed a disturbing trend. “The water is coming off earlier, it’s melting in the mountains quicker.”
Perhaps that’s why trying to coax more snowfall has become an important part of Idaho Power’s business plan. Blestrud says Idaho Power has done research that shows its cloud-seeding is adding 15 percent to the snowpack. They have to, Idaho Power has to ask the state utilities commission for permission to spend that money to implement the program. The only way to receive approval is to show it works. Blestrud says it does, for every foot of snow that falls - that amounts to an extra two inches of new snow from cloud seeding. “If you get more snow pack that’s higher up in the mountains, that’s the stuff that comes off last.”
The deeper the snow is, the longer it stays cool in the spring and early summer. And that helps the snow sticks around longer.
Brandal Glenn, the Idaho Power lead field engineer says “the benefits are immense and there are many, many, many of them…not just making more water. It’s cooling of the rivers, its more water for recreation, it’s more water to run through our water generation system…its just more water.”
Blestrud adds, “the amount of power that can be generated from this is roughly 100,000 megawatts which is enough to power about 700,900 homes for a year.”
Idaho isn’t alone in it’s cloud seeding efforts. It’s a big business in many Western states.
This is where cloud seeding is sometimes controversial. There was a time when it was thought that it robbed a storm of all its moisture. If Idaho cloud seeds, does it keep the rain or snow from falling downwind - say in Wyoming or the Dakotas? Idaho’s Attorney General in the 1960s threatened to sue Oregon over its cloud-seeding program. Such concerns that one state’s cloud-seeding program is stealing precipitation from another state don’t make headlines any more.
“The studies have actually looked into it and they haven’t been able to find an impact down wind,” Idaho Power’s Blestrud says. “They have found either a neutral or positive impact.”
That’s the focus of an intense multi-million dollar pilot project in Wyoming. The final results are expected within the next few years.
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