7196

• UCREFRP Catalog Number: 7196
• Author: O'Brien, J. S.
• Title: Hydraulic and Sediment Transport Investigation Yampa River Dinosaur National Monument 1983 Final Report.
• USFW Year: 1984.
• USFW - Doc Type: Fort Collins, Colorado.
• Copyright Material: NO

2
3) Relate hydraulic and sediment transport data collected in the
Yampa Canyon at Mathers Hole and river mile 16.5 to the
upstream gaging stations.
4) Mathematically simulate the observed flow conditions and
sediment transport for the 1983 runoff season.
5) Predict the minimum streamflow hydrograph which will sustain a
range of natural conditions and processes vital to the
riparian ecology in the cobble bed reach.
After the investigation was initiated the following additional
objectives were appended to the original proposal:
1) Perform a physical model study to calibrate the Helley-Smith
bedload sampler. This flume investigation would also define
the phenomena of sand transport over cobble substrate.
2) Describe the morphological characteristics of the observed
Colorado squawfish spawning reach.
3) Determine the range of discharges that are required to
preserve the morphological conditions that were observed or
projected to have existed during the 1981-3 Colorado squawfish
spawning periods.
The report describes how these objectives were accomplished. Background
information is provided to acquaint the reader with the morphology and
geology of the Yampa River Canyon. In addition, the methods of field
data collection and sample analysis are discussed. The results have
been divided into several sections including; historical flow, sediment
transport, and physical and mathematical modeling. Additional detailed
information on some technical aspects of the investigation are provided
in the appendices.
BACKGROUND
Yampa River Geography and Geology
Dinosaur National Monument is in the northwestern and northeastern
corners of Colorado and Utah, respectively. It lies between Craig,
Colorado and Vernal, Utah. The monument is about 70 miles long (east to
west), and ranges from 10 to 25 miles wide (north to south).
The Yampa River headwaters in the White River National Forest on
the western slope of the Rocky Mountains near Yampa, Colorado. The
Yampa flows north, then west joining the Green River in Dinosaur
National Monument (see Figure 1). It is the Green River's largest
tributary and drains approximately 7600 square miles before entering the
Monument.
An average 1.5 million acre feet of water flow through the Monument
each year in the Yampa, contributing on the average 1.5 to 2.0 million
tons of sediment per year. Almost all of the sand sediment load is