The program in the upper Snake River basin includes 25 remote ground-based generators operated by Idaho Power, 25 manual ground-based generators operated by the High Country Resource Conservation and Development program and one airplane for cloud seeding operations. Idaho Power provides meteorological data and weather forecasting to guide seasonal cloud seeding operations throughout all basins associated with the program.
The technology has been used since the late 1940s to enhance precipitation and also to dissipate fog and reduce the size of hailstones.
A wide range of entities sponsor cloud seeding programs in the U.S. They include municipal, county and state governments; irrigation, water resource and water conservation districts; airports; ski resorts; and private industry. (source: North American Weather Modification Council)
Active programs exist in several states, including Idaho, North Dakota, California, Texas, Colorado, Wyoming, Utah and Nevada.
Idaho Power has developed target-control analyses to evaluate the annual average benefits associated with the collaborative cloud seeding program. Based upon these analyses, the company estimates the cloud seeding programs provide approximately 600,000 acre-feet of additional water in the Payette, Boise and Wood River basins as well as over 400,000 acre-feet of additional water each year in the upper Snake River basin. One million acre-feet of water can generate approximately 844,500 megawatt-hours if used for hydroelectric production — enough to power roughly 74,000 homes.
The IWRB, with support from Idaho Power, studied and reported initial benefits to water supplies in each of the above-mentioned basins. For example, in the upper Snake River basin, preliminary IWRB studies indicate that based upon average water year modeling, up to 32% of the benefits accrue to within-basin natural flow use and 10% to increased reservoir carryover in a 4,000,000 acre-foot reservoir system. The IWRB-managed recharge program benefits by 12% of the water generated and hydropower downstream of Milner Dam improves by up to 13%.
Studies conducted by the Desert Research Institute from 2003 to 2005 and a 2017 study funded by the National Science Foundation support the effectiveness of Idaho Power’s program.
Idaho Power uses two methods to seed clouds: remote ground generators located at high elevation and airplanes that burn special flares within storm clouds. Either method successfully releases silver iodide into passing storms. Minute water particles within the clouds freeze on contact with the silver iodide particles and eventually grow and fall to the ground as snow.
Typically, a well-run cloud seeding program would affect less than 1% of the total available water in a storm system.
For more information, contact:
- North American Weather Modification Council nawmc.org
- Weather Modification Association weathermodification.org
- Shaun Parkinson, PE, PhD, Water Resources Leader, Idaho Power email@example.com
- Derek Blestrud, Senior Atmospheric Scientist, Idaho Power firstname.lastname@example.org