Yampa River Overview

• Description: Yampa River Management Plan
• State: CO
• State: UT
• State: WY
• Basin: Yampa/White/Green
• Water Division: 6
• Date: 1/1/3000
• Title: Yampa River Overview
• Water Supply Pro - Doc Type: Report/Study

of the values (Method B) (Table 6). By averaging the data before it was plotted there
appears to be a smoothing effect to the line at higher flows. This is probably due to the
fact that variability of stream width is less at higher flows. Also inflection points for
riffle cross sections had higher inflections points that for runs and pools for both methods
(Table 6)
Table 6. Mean of inflection points (Method A) / and inflection point of the means
(Method B) for Riffles, Run and Pools above Cross Mountain.
Variable
Units
Riffles
A/B
Runs
A/B
Pools
AIB
Wetted Perimeter
(cfs)
185/150
166/60
178/60
( %)
59%/53%
63%/51%
76%/66%
Wetted Width
(cfs)
207/150
185/60
140/60
(ft)
207/178
200/151
183/155
Average Depth
(cfs)
146/125
168/100
140/100
(ft)
0.67/0.61
1.32/1.19
3.0/2.90
Change in Stage
(cfs)
157/80
146/60
122/125
(ft)
1.21/0.89
1.45 / 0.97
1.21 / 1.15
Width /Depth Ratio
(cfs)
182/200
168/100
193/150
(ratio)
325/307
157/147
75.7/59
Average Velocity
(cfs)
174/125
154/40
143 / NI
(ft/s)
1.58/1.45
0.87/0.40
0.5 / NI
2. Depth, Width/Depth Ratio, Stage and Velocity.
Width/depth ratio was the variable with the next highest mean of the inflection points,
192 cfs (3 10) in Strata 6 and 177 cfs (335) in Strata 8 (Tables 2 and 3). Width/depth
ratios for riffles generally ranged from 100 to 400 in both Strata 6 (Figure 15, Appendix
V.A) and Strata 8 (Figure 15, Appendix VI. A.). A higher width/depth ratio indicates a
wider and shallower habitat and therefore the cross sections with the highest ratios are
those most likely to have limited fish habitat potential and would most likely to become
passage barriers for fish. Width depth ratios were very similar for Strata 6 and Strata 8
21