C153642 Contract

• Contract/PO #: C153642
• Contractor Name: Colorado River Water Conservation District
• Contract Type: MOU
• County: Garfield
• Loan Projects - Doc Type: Contract Documents

Scope of Work
TASK 6: RESERVOIR OPERATIONS STUDIES
The objective of this task is to develop a detailed operational plan for the enlarged
Elkhead Dam and Reservoir in the context of other basin reservoirs and their operation. This
plan will rely on information developed by the USFWS regarding instream tlow requirements
for the endangered tishes. will support environmental analyses and cost estimating activities in
this project and will form the basis for water rights-related and permitting activities in a later
project.
Sub-task 6A. Recalculation of Contemplated Draft
Implement representation of Juniper Project water rights and operations in the existing
basin model. recompute contemplated draft of the project water rights under various
assumptions regarding subordination, transfer, and other limitation of those rights. Define
resulting seasonal values of instream flow rights that might be derived from the Juniper rights.
Sub-task 6B. Refine Operational Hydrology
Review hydrologic data used in the existing basin model paying particular attention to
Elkhead Creek inflows to Elkhead Reservoir. Revise inflow data sets as necessary.
Sub-task 6C. Daily vs. Monthly Hydrology
Investigate methods for estimating daily Clow variation from monthly model results based
on relationships derived from daily streamtlow records. If feasible. develop one or more of
these methods for use in describing model results.
Sub-task 6D. Refine Water Supply Operations
With input from the TSG. scope. define, and carry out additional operations studies
using the basin computer model. These additional operations studies of the enlarged Elkhead
Reservoir will address various assumptions regarding water storage and refill administration,
use of the reservoir for augmentation of junior (to Juniper rights) diverters vs. augmentation of
a junior instream tlow right, maintenance of instream flow conditions in reaches of occupied
habitat, direct water delivery contracts. fish habitat maintenance or enhancement. recreation
pool maintenance, and magnitude and shape of the Juniper contemplated draft as it reflects
possible adjustments to accommodate transfers of portions of the Juniper decrees.
Describe the implications of these alternative operating assumptions and develop
estimates of optimal reservoir size and storage pool allocation rules based on operational
considerations.
Sub-task 6E. Define Recreation and Sport Fishery Plans
Based on existing information, prepare conceptual plans for development and
management of reservoir recreation and fishery potential and for development of a tailwater
fishery below the dam. These plans shall include recommendations for additional data
gathering efforts. Include development of a tish management plan consistent with the goals of
the recovery of the endangered fishes. Evaluate the effects of such recreation and fishery
management plans on water supply operations and sizing of the enlarged reservoir using the
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