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

order to reduce the uncertainty about the frequency of seeding oppor-
tunity, storm variability, and seeding mode operations throughout
the Basin, two subbasins would be instrumented simultaneously.
Basin-wide climatological studies to determine storm types and seeding
opportunities would be initiated during the initial phase and continued
throughout the second phase.

The 4-year second phase would include a randomized seeding program in
two subbasins to evaluate and quantify water supply increases and
extrapolate this information to the entire Basin. Concurrent studies
to improve project instrumentation, seeding modes and agents, would be
conducted in preparation for Basin-wide operations. Data required to
implement transfer of the technology to the other subbasins of the
Colorado River would be collected.

The advantages of this option are that it calls for the earliest initia-
tion of Basin-wide operations, it anticipates increased water supply in
two subbasins within 2 yearsl. and it has the lowest total cost of all
the options. The disadvant;:iges are that the scientific and social
acceptabi 1 ity of the results of the 6-year effort probably wi 11 not be
at a high enough level of confidence for those concerned with issues of
extra-area effects, water rights, and soci al and envi ronmental effects
to initiate a Basin-wide program. With only 2 years to prepare for the
demonstration phase, there is no opportunity to improve on existing
technology. Also, it may not be possible to complete the needed envi-
ronmental studies and impact statement in 2 years. This option has the
highest average annual costs.

C. Programmatic Alternatives

The Project Skywater programmat i c Fi nal Env i ronmental Statement [2J was
filed with the Council on Environmental Quality, October 25, 1977. The
Statement was distributed to State clearinghouses; Federal, State, and
local agencies; universities and colleges; special interest organizations;
and the general public in the Colorado River Basin. Chapter 8 of the
Statement, "Alternatives to the Proposed Action," is incorporated by
reference as part of thi s envi ronmental assessment. The eight program-
matic alternatives discussed in the FES in addition to precipitation
management are:

- the null or no-action alternative
- accommodating to projected \>'rater shortages
- expanded conventional water resources engineering
- geothermal waters
- saline waters
- interbasin or intrabasin water transfers
- water reclaimed through conservation
- alternative technologies applicable to the atmospheric water resource

Continued investigation or implementation of one or any combination of
the programmatic alternatives in a particular region does not preclude
consideration of the remaining alternatives. Certain alternatives, or
combinations of alternatives, may be complementary. Thus, development of

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