7750

• UCREFRP Catalog Number: 7750
• Author: U.S. Bureau of Reclamation.
• Title: Study of Alternative Water Supplies for Endangered Fishes in the "15-Mile Reach" of the Colorado River.
• USFW Year: 1992.
• USFW - Doc Type: \
• Copyright Material: NO

CHAPTER I
Study Activities

1
INTRODUCTION
Environmental commitments related to the sale of water from Ruedi Reservoir have resulted
in 5,000 acre-feet (AF) of water from the reservoir's regulatory capacity being withheld from
sale for delivery to and through the 15-Mile Reach for the benefit of the endangered fish
species. In addition, changes in the operation of the reservoir will provide an additional
5,000 AF on an average of 4 out of 5 years. However, the FWS has determined that
additional water over and above the current supply from Ruedi will be required in the months
of July, August, and September to provide adequate flows in the 15-Mile Reach for the
endangered fishes. Consequently, the Implementation Committee requested that Reclamation
conduct this study to identify possible sources of additional water for the 15-Mile Reach.
Reclamation performed the study in cooperation with the Colorado River Water Conservation
District, the FWS, and the Colorado Water Conservation Board.
Study Goals and Objectives

1

1
1

1

The objectives of this study were to identify and evaluate alternate sources of water supply
for the Reach. Once alternative sources were identified, an appraisal-level cost estimate of
developing the water was prepared. When appropriate costs are presented as a one-time
capital cost and an equivalent annual costs. All annual cost were amortized at 8-5/8 percent
interest over 50 years.
An initial environmental screening has been performed for each alternative and a brief list of
the environmental impacts of each alternative was prepared. The study also identified
potential institutional, legal and water user constraints which could affect the viability of an
alternative, but recommendations were not made concerning how such constraints might be
addressed.
Before any alternative could be implemented a thorough analysis of the legal, institutional
and water user constraints must be completed and resolved. A programmatic final
environmental assessment on the Recovery Implementation Program for Endangered Species
in the Upper Colorado River Basin was completed in 1987. Site- or project-specific
documents complying with the National Environmental Policy Act (NEPA) will be required
before any water supply alternatives are implemented. All alternatives, if developed, would
be implemented under the State's instream flow program.
The study examined the following alternatives:
(1) Releases of stored water from existing reservoirs;
(2) Releases of stored water from new reservoirs;
3