9349

• UCREFRP Catalog Number: 9349
• Author: Fischer, N. T., M. S. Toll, A. C. Cully and L. D. Potter.
• Title: Vegetation Along Green and Yampa Rivers and Response to Fluctuating Water Levels, Dinosaur National Monument.
• USFW Year: 1983.
• USFW - Doc Type: Albuquerque.
• Copyright Material: NO

slowed by an obstruction of rubble (as above Big Joe and Warm Springs
Rapids) or where the water eddies below a constriction of the channel (at
Anderson Hole and Haystack Rock). Meanders are also areas of sand
deposition, particularly along the inner curves where the current is slow.
Gravel bars and islands occur periodically along the entire length of the
river in a variety of channel situations.
The Green River from Lodore Ranger Station to Echo Park
The 18.5 miles of river between Lodore Ranger Station (mile 243.7, from
the confluence with the Colorado River) to Echo Park flows generally
southward through the deep and narrow Canyon of Lodore, named in 1869 by
J.W. Powell. In one section of this canyon (between Rippling Rock and
Limestone Draw) the right wall rises over 3000 ft. above the river. By
contrast, the highest wall on the Yampa is 1700 ft. in the area of Warm
Springs.
The sinuosity of this section of river is 1.27, we 11 below the level of
a meandering river. The vertical drop is 275 ft., giving it an average
gradient of 14.9 ft./mile. The range of gradients runs from 1 ft./mile at
the ranger station and immediately above Disaster Falls (mile 237) to a drop
of 30 feet in a half mile at He11's Half Mile (mile 231.8). The upper six
miles are relatively flat, averaging 2.5 ft./mile, while the lower 12.5
miles drop rapidly at 18.2 ft./mile.
The geology of the canyon is relatively uniform with two formations
not encountered on the Yampa. These are:
1. The Uinta Mountain Group (Precambrian)
11
The upper 15.5 miles of the Canyon of Lodore are cut into these very