7285

• UCREFRP Catalog Number: 7285
• Author: Stewart, J. M.
• Title: Summary of Water-Resources Activities of the U.S. Geological Survey in Colorado, Fiscal Year 1987.
• USFW Year: 1987.
• USFW - Doc Type: Open-File Report 87-388,
• Copyright Material: NO

PROJECT TITLE:

Comprehensive Hydrologic Quantity
and Quality Model of the Arkansas
River basin, Colorado

PROJECT NUMBER:

CO-82-159

STUDY LOCATION:

The Arkansas River basin of
southeastern Colorado

COOPERATING AGENCY:

Southeastern Colorado Water
Conservancy District

PROJECT CHIEF AND
OFFICE:

Alan Burns, District Office, Lakewood

PROJECT DURATION:

October 1981 to September 1988

PROBLEM: Major changes in water use and resultant water qual ity in the
Arkansas River basin are having impacts on all water users. The current
over-appropriation of surface-water supplies has led to a complex water-
supply system of transmountain diversions, reservoir storage, and devel-
lopment of the alluvial aquifer. Currently no consistent, comprehensive
means exist to assess the possible water-quantity and -quality effects of
the many possible changes in the competing water uses.

OBJECTIVE: Construct and document a model capable of assessing the basinwide
quantity and quality impacts resulting from changes in water use. This
model would be an interactive, planning-type, stream-network model to
simulate the impact of the adjacent alluvial aquifer, simulate a water-
quality mix, and include the legal-priority system of Colorado water law.

APPROACH: Deve lop the model from exi st i ng stream-network and stream-aquifer
models. Develop stream-aquifer response functions, precipitation-runoff
relations, water-quality discharge relations, and irrigation application-
recharge factors for entry into the model. Cal ibrate and demonstrate
examples of the model's predictive capabilities in workshops and describe
them in a report.

PROGRESS: Two reports are pub 1 i shed: one descri bi ng the water ope rat ions of
the basin and the other summarizing hydrographs and statistics of the
water resources of the basin. A report describing water-quality rela-
tions in the basin is approved for publication. A report documenting the
model has been transmitted for final approval, and a report describing
the model calibration is being revised after review. A bibliography of
water-resources investigations in the basin will be developed, and the
model data base will be updated.

PLANS FOR FY 87: All reports will receive Director's approval; data base will
be updated, and model will be revised to include capability to use daily
distribution of streamflow within a month of occurrence to make monthly
simulation of diversions more realistic.

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