7387

• UCREFRP Catalog Number: 7387
• Author: U.S. Bureau of Reclamation.
• Title: Glen Canyon Environmental Studies Executive Summaries of Technical Reports.
• USFW Year: 1988.
• USFW - Doc Type: \
• Copyright Material: NO

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THE RAPIDS AND WAVES OF THE COLORADO RIVER
GRAND CANYON, ARIZONA

The hydraulics and geomorphology of 12 rapids on the
Colorado River are described in this report, on a 20-
min VHS videotape1 (U.S. Geological Survey [USGS] Open
File Report 86-503), and on ten hydraulic maps (USGS
Miscellaneous Investigations map 1-1897, parts A-J).

By Susan Werner Kieffer
Branch of Igneous and Geothermal Processes
U.S. Geological Survey
Flagstaff, Arizona

INTRODUCTION

Each rapid of the Colorado River is unique, but the
major rapids have many hydraulic features in common.
In this report, I describe the general features of 12
of the major rapids of the river in Marble Canyon and
Grand Canyon, and address the following topics: (1)
definition of the hydraulic and geomorphic features at
rapids: (2) location of the rapids in terms of geologic
structures of the Colorado Plateau: (3) channel geom-
etry and hydraulic structures: (4) causes of rapids,
pools, and scour holes: (5) a generalized hydraulic
model for rapids: (6) hydraulic nature of pools and
backwaters: (7) hydraulic nature of tongues and lateral
waves: (8) breaking waves in the rapids: (9) behavior
of water near large rocks within rapids: (10) movement
of boulders and erosional contouring of the river chan-
nel at rapids: (11) the relation of rapids to rock
gardens below them: and (12) minor effects, such as
curvature of the river at rapids.

OBJECTIVES

Work on the Colorado River by Howard and Dolan (1976),
related work by Graf (1980) on similar rivers, and pre-
liminary work done at Crystal Rapid by Kieffer in 1983
(Kieffer 1985) has demonstrated that Grand Canyon ra-
pids have changed since Glen Canyon Dam was closed in
1963. Data on the shape of the river channel and the
material that lines it are conspicuously absent and
are needed before response of the rapids to discharges

1 The video may only be obtained by requesting it
from the author (U. S. Geological Survey, 2255 Gemini
Drive, Flagstaff, Arizona 86001.

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