The moisture suspended in the atmosphere is a natural resource. It has been estimated that only about 2% to 3% of the moisture in the atmosphere falls as natural precipitation. Moisture which falls naturally or is artificially induced to fall as precipitation within Colorado is the property of the people of the state. Cloud seeding, the primary weather modification (WM) activity, is the intentional treatment of individual clouds or cloud systems to achieve some desired effect. The Colorado General Assembly has declared that the State of Colorado recognizes that economic benefits can be derived for the people of the state from weather modification. Operations, research, experimentation, and development in the field of weather modification shall therefore be encouraged. Colorado has had operations and research conducted in the state since the 1950s and there has been a program to permit weather modification since 1972. After the significant drought starting in early 2000, many new WM permits have been developed. Currently there are permits for: Western San Juan Mountains, Eastern San Juan Mountains, Telluride/Upper San Miguel Basin, Gunnison County, Upper Gunnison River Tributaries, Grand Mesa, Upper Arkansas Basin, and the Central Rockies (Denver Water). The CWCB has developed a cost share grant program that is designed to assist local water users in funding WM activities for its perceived importance to managing water supplies.
Administration of Colorado’s Weather Modification Permit Program is the responsibility of the Executive Director of the Department of Natural Resources. This responsibility was delegated to the Director of the Colorado Water Conservation Board in 1987. State Statutes and Rules which govern the control of issuing permits for weather modification in Colorado can be found on our Statutes
The General Assembly decided in 1996 that the state should continue to issue permits in order to monitor and keep the public informed about weather modification activity. While weather modification licenses were eliminated, the qualifications for operating a weather modification program were made part of the permitting process. See the Permit Program page for further information on weather modification permits and the permitting process.
Recent weather modification publications can be found on our Publications page.
The State of Colorado issues permits for cloud seeding and monitors snowpack, avalanche hazards and other environmental conditions during winter and will curtail cloud seeding programs when warranted.
The Colorado Avalanche Information Center provides daily forecasts via a website for avalanche hazard levels at mountain passes and roads. The CWCB staff, program sponsors, and permit holders use this website and expert information to suspend cloud seeding activity in areas with high snowpack and hazard levels.
The NRCS Snow Survey Program maps all 102 SNOTEL sites each day for the State of Colorado thresholds for snowpack snow water equivalent. Once SNOTEL site readings are nearing the high end of a 30-year average for that site, it will trigger a temporary suspension of all cloud seeding activity that would affect those mountain ranges.