8221

• UCREFRP Catalog Number: 8221
• Author: Van Steeter, M. M.
• Title: Historic and Current Processes Affecting Channel Change and Endangered fish Habitats of the Colorado River Near Grand Junction, Colorado.
• USFW Year: 1996.
• USFW - Doc Type: Doctor of Philosophy.
• Copyright Material: NO

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The drainage area above the 15 mile reach is approximately 23,300
square kilometers (9,000 mi2), and the mean river slope is 0.0017. The
mean annual flood at the Cameo gauge is 560 cms (19,700 cfs), and the
mean annual flow is 110 cms (3,870 cfs) (Table 2.1). This reach contains
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potentially important spawning habitat for the Colorado squaw fish which

Table 2.1. Characteristics of the 15 and 18 mile reaches of the Colorado
River

-------------------------------------------------------------------------------------------------------

drainage area
(km2)

mean slope

mean
discharge (ems)

mean
flood (cms)

15 mi reach

23,300

0.0017

110

560

18 mi reach

44,000

0.0012

175

775

showed spawning activities at river mile 178.3 in the early 1980s
(Osmundson and Kaeding, 1989). Larval Colorado squawfish continue to
be found downstream indicating possible spawning in the 15 mile reach
(Kaeding and Osmundson, 1989).
The 18 mile reach extends from the confluence of the Gunnison

River to river mile 153 (Figure 2.1). The drainage area upstream of here is
approximately 44,000 square kilometers (17,000 mi2). The slope of this
reach is 0.0012. At the State line gauge, the mean annual flood is 775 cms
(27,300 cfs), and the mean annual discharge is 175 cms (6,200 cfs) (Table 2.1).

Like the 15 mile reach, this reach also contains potential spawning sites.
Ripe adult Colorado squawfish are found in this reach every year, and a
potential spawning bar was identified in 1994 near river mile 169 (Doug

Osmundson, personal communication).