7884

• UCREFRP Catalog Number: 7884
• Author: Hydrosphere Resource Consultants.
• Title: Reconnaissance Evaluation of Yampa River Diversion Structures.
• USFW Year: 1995.
• USFW - Doc Type: Boulder, CO.
• Copyright Material: NO

Introduction
This reconnaissance evaluation is meant to provide the necessary technical information
for informed decision-making about the direction of more detailed studies. It provides
preliminary recommendations for further study and modification of specific structures but does
not address changes in the regulation of diversion structure maintenance activities.
CITY OF CRAIG MUNICIPAL DIVERSION
Historically, municipal diversions from the Yampa River mainstem for the City of Craig
were made via temporary gravel/cobble structures pushed into place during low flow periods
similar to what is done for agricultural diversions. However, these municipal diversion
maintenance activities were not exempt from the Section 404 permitting requirements of the
Clean Water Act. Furthermore, maintenance was estimated to cost the City roughly $10,000
annually.
In 1991 the City began the process of designing a permanent diversion structure to
maintain water levels at the municipal intake. An interdisciplinary design process was
undertaken in close consultation with the U.S. Fish and Wildlife Service ("Service") to insure
that the structure would not impede the passage of endangered fish under a wide range of flow
conditions. The structure, which consists of a concrete cutoff wall and extensive placement of
natural boulders, was completed in 1992 at a total cost, including fisheries and boat passage
studies and engineering design services, of roughly $300,000. Annual maintenance costs are
now estimated to be roughly $500 and the improved raw water quality has reduced annual
municipal treatment costs by an estimated $5,400.
In 1993 the project won the Grand Prize for Excellence in Environmental Engineering in
the small projects category from the American Academy of Environmental Engineers as a
model of cooperation and innovation. The design and construction process focused attention on
the potential fish passage problems at agricultural diversions. The City of Craig's design is
being considered by the Bureau of Reclamation and the Service for use at several other
locations within the Colorado River basin and is highlighted here as an in-basin example of
how typical diversion practices might be modified to achieve multiple objectives.
Selected photographs and design drawings of the new Craig diversion structure are
contained in Appendix B.
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