Grand Canyon Studies

Using Ocean-Research Techniques to Study a River System

Since the early 1960's, the flow of the Colorado River through the Grand Canyon has been controlled by Glen Canyon Dam (see map).

A team of researchers from many disciplines has been studying the effects of the dam for more than a decade. These studies began in response to concern about changes the dam's operations have produced in the Grand Canyon ecosystem. Some of those changes are

• a decline in the size and number of sandbars used as campsites by river rafters and backpackers,
• an increase in the abundance and diversity of vegetation along the river, and
• a decline in populations of native fish.

One of the contributions of the USGS to these studies is the use of ocean-research techniques--such as sidescan sonar--to investigate sediment in the Grand Canyon.

Effects of Controlled Flood Now Being Studied

The purpose of these test flows was to determine if periodic large releases of water from Glen Canyon Dam can rebuild sandbars and restore other habitats that have deteriorated since the dam's completion in 1963.

Suggestions for further reading