7397

• UCREFRP Catalog Number: 7397
• Author: Resource Consultants, I.
• Title: Draft Supplement to the Final Environmental Statement Colorado-Big Thompson, Windy Gap Projects Water Marketing Program for Green Mountain Reservoir, Colorado.
• USFW Year: 1985.
• USFW - Doc Type: Fort Collins.
• Copyright Material: NO

Alternative 2. Full Sales/Exchange with Only Hydrologic Constraints.
Under this alternative the impacts of full sales or exchange to meet all of
the currently identified requests for water (approximately 22,800 acre-f~et)
are evaluated. A review of the requests for water from Green Mountain
Reservoir (Table 2.1 and in Appendix A) reveals that many requestors are
located above Green Mountain Reservoir in the Blue River drainage or on the
Fraser or Eagle river systems. For these requestors, diversions and/or
depletions would be made to the flow of small, upper watershed streams, and
corresponding releases from Green ~10untain Reservoir would replace the
depletion to the Colorado River system below the reservoir. Water sales to
these requestors imply an exchange of water above Green Mountain Reservoir.

Under this alternative, the physical (hydrologic) constraints of the
system to deliver requested water sales will be assessed. Essentially all
water requests will be met except where streams are physically incapable of
delivering the amount of water at the time requested. At this level of
water sales a shortage of from zero percent to 30 percent might have to be
imposed in some months of some years because of operational limitations on
the ability of Green Mountain Reservoir and the Colorado River system to
deliver water under certain hydrologic conditions (see Section 4.6).

Alternative 3. Full Sales/Exchange with Instream Flow Constraints.
This alternative considers the same level of water sales (22,800 acre-feet)
as Alternative 2, however, currently recommended or appropriated instream
flow values by the Colorado Water Conservation Board are assumed to repre-
sent a potential added constraint on the diversion or depletion of stream-
flow. This added constraint could be particularly important for those
water requestors anticipating use of Green Mountain water as a basis for
exchange from the smaller, headwater streams in the Fraser River, Blue
River, and Eagle River drainages. Under this alternative, many water
requests would not be met in full during some months of some years due to
instr~am flow constraints. As with Alternative 2, a shortage of from zero
to 30 percent might have to be imposed in some months of some years because
of operational limitations on the ability of Green Mountain Reservoir and
the Colorado River system to deliver water under certain hydrologic condi-
tions (see Section 4.6).

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