Skip Links

USGS - science for a changing world

U.S. Geological Survey Scientific Investigations Report 2010-5015

Prepared in cooperation with Northern Arizona University and Utah State University

Sandbar Response in Marble and Grand Canyons, Arizona, Following the 2008 High-Flow Experiment on the Colorado River

By Joseph E. Hazel, Jr., Paul E. Grams, John C. Schmidt, and Matt Kaplinski

ABSTRACT

Thumbnail of and link to report PDF (18 MB)

A 60-hour release of water at 1,203 cubic meters per second (m3/s) from Glen Canyon Dam in March 2008 provided an opportunity to analyze channel-margin response at discharge levels above the normal, diurnally fluctuating releases for hydropower plant operations. We compare measurements at sandbars and associated campsites along the mainstem Colorado River, downstream from Glen Canyon Dam, at 57 locations in Marble and Grand Canyons. Sandbar and main-channel response to the 2008 high-flow experiment (2008 HFE) was documented by measuring bar and bed topography at the study sites before and after the controlled flood and twice more in the following 6 months to examine the persistence of flood-formed deposits. The 2008 HFE caused widespread deposition at elevations above the stage equivalent to a flow rate of 227 m3/s and caused an increase in the area and volume of the high-elevation parts of sandbars, thereby increasing the size of campsite areas. In this study, we differentiate between four response styles, depending on how sediment was distributed throughout each study site. Then, we present the longitudinal pattern relevant to the different response styles and place the site responses in context with two previous high-release experiments conducted in 1996 and 2004. We find that (1) nearly every measured sandbar aggraded above the 227-m3/s water-surface elevation, resulting in sandbars as large or larger than occurred following previous high flows; (2) reaches closest to Glen Canyon Dam were characterized by a greater percentage of sites that incurred net erosion, although the total sand volume in all sediment-flux monitoring reaches was greater following the 2008 HFE than following previous high flows; and (3) longitudinal differences in topographic response in eddies and in the channel suggest a greater and more evenly distributed sediment supply than existed during previous controlled floods from Glen Canyon Dam.

  • This report is available only on the Web.

For additional information contact:
SBSC Staff, Southwest Biological Science Center
U.S. Geological Survey
2255 N. Gemini Drive
Flagstaff, AZ 86001
http://sbsc.wr.usgs.gov/

This report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.


Suggested citation:

Hazel, J.E.., Jr., Grams, P.E., Schmidt, J.C., and Kaplinski, M., 2010, Sandbar response in Marble and Grand Canyons, Arizona, following the 2008 high-flow experiment on the Colorado River: U.S. Geological Survey Scientific Investigations Report 2010-5015, 52 p.



Contents

Abstract

Introduction

Physical Setting

Controlled Floods, Tributary Sand Inputs, and Fluctuating Flows

Methods

Results

Discussion and Conclusions

Acknowledgements

References Cited

two appendixes


Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http:// pubs.usgs.gov /sir/2010/5015/index.html
Page Contact Information: USGS Publications Team
Page Last Modified: Thursday, 10-Jan-2013 19:06:18 EST