8279

• UCREFRP Catalog Number: 8279
• Author: Brown and Caldwell.
• Title: Phase 1 Coordinated Facilities Water Availability Study for the Endangered Fishes of the Upper Colorado River.
• USFW Year: 2000.
• USFW - Doc Type: \
• Copyright Material: NO

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CHAPTER 2
GROUND RULES AND ASSUMPTIONS
' 2.1 INTRODUCTION
The Executive Committee and the consultant team established ground rules under which this
' preliminary feasibility investigation of alternatives for supplying an annual average of 20,000
acre-feet of water in those years when the forecast spring peak flows are between 12,900 cfs and
' 26,600 cfs would proceed. The Executive Committee and the team also identified assumptions
that are necessary to facilitate the study. The purpose of this section is to detail the ground rules
and assumptions that have been made for this investigation and to provide explanation and
' justification for these ground rules and assumptions. The frequency and certainty with which the
average annual 20,000 acre-feet will be made available is detailed in the Flow Targets section
below.
2.2 GROUND RULES
2.2.1 Administration
Recommended alternatives from this investigation do not need to include recommendations for a
' mechanism for administration or legal protection of water released or otherwise supplied during
the spring peak to the head of the 15-Mile Reach. This is because there is unappropriated water
available during the spring peak in years when flows at the head of the 15-Mile Reach are in the
' range of 12,900 to 26,600 cfs. From an administrative standpoint, the river is under "free river"
conditions, and therefore administration of flows past intervening water rights is currently
unnecessary. As specified in the PBO, any new depletion during this period of the year may be
' covered under the PBO. For the same reason, the conversion of water rights to instream flows in
order to protect and convey flows to the head of the 15-Mile Reach during the spring peak will
not be considered further.
' With regard to the secondary study purpose of providing flows in the late irrigation season,
potential administrative mechanisms will need to be identified to protect the water to and through
the 15-Mile Reach because the river is generally on call during that time of the year.
This report raises issues with regard to the propriety of releasing water from, or bypassing water
' at, storage facilities as it relates to specific water rights, project authorization or accounting of
individual projects. These issues are further discussed below and under each alternative.
' During Phase 1, the issue of how bypassed diversions to storage would be administered has been
discussed. Several alternatives for administration exist:
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