2 Colo. Code Regs. § 401-1-17
Current through Register Vol. 47, No. 7, April 10, 2024
Rule 2 CCR 401-1-17 - Suspension of Weather Modification OperationsA.Ground-Based Winter Cloud Seeding: The permit holder must suspend ground-based winter cloud seeding operations when the following conditions are in the target area:(1) Snow Water Equivalent Thresholds. Weather modification operations must be suspended at any time the snowpack water equivalents exceed the following: 175% of average on December 1st, 175% of average on January 1st, 160% of average on February 1st, 150% of average on March 1st and 140% of average on April 1st. The Director or his or her designee will determine where and how snowpack water equivalents are to be measured, including at selected "SNOTEL" sites. The Director or his or her designee may permit weather modification operations to continue in a portion of the operation target area where snowpack water equivalents are below these suspension criteria percentages, if the operation will not impact the area where snowpack water equivalents are above these suspension criteria percentages. These thresholds are designed to keep the seeding effect to within the realm of natural variability of the local climate as measured at each SNOTEL station.(2) Avalanche Hazard Levels. Weather modification operations may be suspended by the Director due to high avalanche hazard levels, and must be suspended by the permit holder due to extreme avalanche hazard levels for highway corridors, as determined by the Colorado Avalanche Information Center (CAIC). The CAIC works in coordination with the Department of Transportation and National Weather Service to determine avalanche hazard levels. The permit holder must monitor CAIC avalanche hazard levels, and coordinate with the Director and CAIC to determine whether suspension of operations is warranted by high avalanche hazard levels. (3) National Weather Service Hazardous Weather Statements. The permit holder must suspend all weather modification operations whenever one of the following is issued that impacts any part of the target area:a. An urban or small stream flood advisory;c. A flash flood warning; or d. A severe thunderstorm warning. Operations may resume after these statements expire.
B.Aerial Summer Cloud Seeding: The permit holder must suspend aerial summer cloud seeding operations when the National Weather Service has issued a flash flood warning, storms are producing a funnel cloud or tornado, or the operational meteorologist observes any condition that warrants temporary suspension of the program. The permit holder must suspend winter aerial cloud seeding operations according to the suspension criteria of Rule 17.A.C.Other Weather Modification Operations: The Director may determine and implement suspension criteria for other types of weather modification operations, as necessary. For example, hail cannon weather modification operations must be confined to a small localized area directly over the target area, and limited to periods of heavy rain and hail tracking directly toward and over the target area.