1400 ‎(2)‎

• UCREFRP Catalog Number: 1400
• Author: Simons, D. B., et al., ed.
• Title: Proceedings
• USFW Year: 1980.
• USFW - Doc Type: Workshop on Downstream River Channel Changes Resulting From Diversions or Reservoir Construction.
• Copyright Material: NO

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DOWNSTREAM RIVER CHANNEL CHANGES FROM
DIVERSIONS OR RESERVOIR CONSTRUCTION

INTRODUCTION

Daryl B. Simons
Director, Engineering Research Center and Professor, Civil Engineering,
Colorado State University, Fort Collins, Colorado

BACKGROUND

River systems are an integral part of the fluvial ecosystem.
Streamfl ows, sedi ment tran sport rates, and channe 1 morphology refl ect
the major responses resulting from river utilization activities.
Knowledge of river mechanics, geomorphology, and watershed management is
essential for formulating and selecting design alternatives by planners
or engineers or both. The basic principles affecting the dynamics and
response of streams to natural conditions or manmade alterations, or
both, are not generally covered in college curricula, particularly at
the undergraduate level. An understanding of stream mechanics is
necessary for the proper p 1 ann i ng and design of any channel change.
Thi s is particuhrly true of work in natural streams that carry heavy
sediment loads. Analysis using principles of stream mechanics, that is
a dynamic approach as compared to a static, rigid boundary approach,
provides a more realistic understanding of channel response to man-
induced changes. In response to this need, the U.S. Fish and Wildlife
Service organized a workshop on the response of river systems to major
impoundments or flow diversions.

This workshop assembled 20 of the world's most qualified
individuals to discuss solutions to downstream problems stemming from
hypothetical impoundments or diversions, or both, on three selected
Western United States rivers. The participants were chosen from varied
disciplines including geology, geomorphology, river mechanics, erosion
and sedimentation, hydraulics, hydrology, fisheries and aquatic biology,
and water quality. Each of the participants was an expert in one of
these areas and possessed some understanding of all topics to facilitate
a productive exchange of ideas.

Results of this workshop include this set of proceedings composed
of reports prepared by the 20 participants along with reporters'
comments and workshop summaries. These reports describe how each author
perceives the problem of river response and determines a solution to a
set of hypothetical man-induced changes. Reports were submitted before
the workshop, reviewed within the group of workshop participants, and
revi sed and resubmi tted by the authors after the workshop.

The workshop offered a unique opportunity for a group of highly
qualified people to present, exchange and discuss concepts, theories,
and methodologies regarding the response of river systems to various
types of development. The primary objective of the workshop was this
set of papers which covers a wide spectrum of viewpoints and was