WMOD00422

• Project Name: Colorado River Enhanced Snowpack Test
• Title: CREST - Environmental Assessment and Design Phase - Finding of No Significant Impact
• Date: 4/1/1981
• Weather Modification - Doc Type: Report

well-being as well as hazardous situations. For example, during the
1970-75 period of the Colorado River Basin Pilot Project, Water and
Power suspended its research seedi ng program in the autumn until
after the big-game hunting season so as not to risk causing precip-
itation increases that might interfere with this annual event. The
hunting season on Colorado's western slope merits local and national
tourist attention and has significant economic impact in the area.

3. Minimization of Cloud Seeding Risks

Research and operational cloud seeding activities have resulted in
identification of certain recurring questions related to enhancement of
winter precipitation in mountainous areas. Continuing scientific
investigation and project field experience have laid some of these
questions to rest, and have categorized the degree of risk that may
still be at issue with the remaining concerns. Ongoing research
results have provided the basis for minimization or mitigation of
precipitation-related risks.

Common areas of concern in winter orographic snowfall enhancement
include excess snowpack accumu"lation, avalanches, flooding and severe
storms. Studies of project basin hydrology and analyses of basin
climatology provide the scientHic information required to develop a
suspension criteria system under which seeding operations will be
discontinued if it appears the physical or economic well-being of the
area and its residents are endangered by weather activity. Suspension
criteri a designed to prevent harm to the project area as the result of
excess snowpack accumulation, avalanches, flooding, and enhanced severe
storms were in effect during thE~ 5-year, 1970-75 period of the Colorado
River Basin Pilot Project. No unusual, abnormally hazardous, or other
type of weather condition outside normal wintertime variability was
identified during the Pilot Project that was attributed to seeding-
related increases in snowfall. Additional information and continuing
analysis resulting from ongoing cloud seeding activities will diminish
unknown areas and decrease the risk related to wintertime cloud seeding.

D. Programmatic Alternatives

The environmental consequences of the various programmatic alternatives,
such as development of geothermal or saline resources, are discussed in the
Project Skywater Programmatic FES [2J in Chapter 8. This discussion is
incorported by reference into this Environmental Assessment.

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