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We all know that clouds produce rain (and snow!). But scientists have proven that we can “encourage” clouds to produce even more snow through a process called cloud seeding.

4-Peaks-With-Snow-01Central Arizona Project, along with the Southern Nevada Water Authority and Metropolitan Water District of Southern California has funded pilot snowpack augmentation programs in Colorado, Utah and Wyoming since 2006. These programs use ground-based cloud seeding generators located at elevations above 8,000 feet. The generators burn silver iodide, which enhances the formation of cloud droplets. These cloud droplets may then precipitate as snow during winter months, thus increasing the snowpack that is the source of spring and summer runoff to the Colorado River. CAP estimates this pilot project has generated about 30,000-acre feet of additional Colorado River water.


Research shows that silver iodide does not persist in the environment after the snow melts and that “down-wind effects” (often referred to as “cloud rustling”) are not a factor in winter cloud seeding. Additional published research conducted by the National Oceanographic and Atmospheric Administration, the National Center for Atmospheric Research and the University of Wyoming, show that ground-based cloud seeding can and does increase ice crystal formation and snow fall.

Cloud seeding is one of the least expensive methods of water augmentation and holds great promise in mitigating the short-term effects of drought and the long-term projected Colorado River shortage.


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