WSPP282

• File Number: 8240.200.39.C
• Description: Colorado River Threatened-Endangered - RIPRAP - CFOPS - Water Availability
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 3/1/2003
• Author: Brown and Caldwell
• Title: Phase 2 Coordinated Facilities Water Availability Study for the Endangered Fishes of the Upper Colorado River - Tech Memo Number 12 - Comments-Responses to 01-01-03 - Draft - 03-01-03
• Water Supply Pro - Doc Type: Report/Study

OOLJ722

2.2.3 Evaluation and Screening Criteria

Participants in this Phase 1 investigation indicated the importance of three criteria for evaluating and
screening alternatives:
. Reduction in existing projects' yields is not to occur,
. Existing projects' operations and maintenance costs should not be increased, and
. Existing projects operational flexibility, and/or reliability are not to be affected.

Analysis has been completed in Phase 2 to help quantify these evaluation criteria for the alternatives
to supply the average annual 20,000 acre-feet.

2.2.3.1 Impact on Existing Projects' Yields. The term "yield" is used in this investigation to
indicate the historic yield of a project under historic hydrologic conditions and does not refer to the
decreed yield of the project's water right. In Phase 2 of this investigation, extensive analysis has been
completed to determine the effect, if any, of implementing the alternatives described in this report on
existing projects' yields and storage. These effects were determined by comparing hydrologic model
simulations with and without the proposed alternatives.

2.2.3.2 Effect on Existing Projects' Operations and Maintenance Costs. Analysis of effects of
alternatives on existing projects' operations and maintenance costs has been completed as part of this
investigation in those situations where operations and maintenance costs could be affected.

2.2.3.3 Effect on Existing Projects Operational Flexibility or Reliability. Analysis of effects of
alternatives on existing project operational flexibility or reliability has been completed as part of this
investigation in those situations where operational flexibility or reliability could be affected.

2.2.4 RIPRAP Alternatives

The feasibility of expanding or modifying certain of the RIPRAP alternatives as listed in the PBO and
the Recovery Implementation Program (U.S. Fish and Wildlife Service, December 20, 1999) was
considered and these alternatives were investigated. Yield available from a specific modification
and/ or expansion of the RlPRAP alternatives is counted toward meeting the 20,000 acre-feet target if
(1) this yield was in addition to the yield of the original RIPRAP alternative and (2) the
modified! expanded alternative would not diminish the yield of the original RIPRAP alternative.

..

2.2.5

Incentives for Participation

Participation in actions identified in the PBO is voluntary. The PBO examined both existing and
future depletions on the Colorado River and its tributaries upstream of the confluence of the
Gunnison River associated with Federal, State, and private projects which rely on, or will rely on, the
Recovery Action Plan (RAP). The Service believes that these RAP items are sufficient to avoid the
likelihood of jeopardy and/or adverse modification of critical habitat from: (1) depletions occurring
as of September 30, 1995 from existing individual projects, and (2) future depletions up to
120,000 acre-feet/year. Individual Section 7 consultation will still be required on specific Federal

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