7051

• UCREFRP Catalog Number: 7051
• Author: Andrews, E. D.
• Title: Downstream Effects of Flaming Gorge Reservoir on the Green River, Colorado and Utah
• USFW Year: 1986
• USFW - Doc Type: Geological Society of America Bulletin
• Copyright Material: YES

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- PRE.RESERVOIR
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500

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5 10 20 30 40 5060 70 80 90 95 98 99 99.8 99.9
DURATION OF DISCHARGE 1 % TIME I

0.05 O. I 0.5 1 2

E. D, ANDREWS

40.000

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DURA TION OF DISCHARGE ". TIME'

998 99.9

Figure S. Comparison of the duration for daily mean discharges
during the pre- and post.reservoir periods measured at the Green
River near Greendale, Utah, gage.

Figure 6. Comparison of the duration for daily mean :Idischarges
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during the pre. and post-reservoir periods measured at 1 the Green
River near Jensen, Utah, gage.

channel of the Green River will adjust over a
period of years to the locally prevailing effective
discharge.
Detailed information describing the bankfull-
channel dimensions of the Green River is lim-
ited, especially prior to construction of Flaming
Gorge Dam. All of the gaging stations used in
this investigation have rated cross sections where
the discharge is measured several times a year.
These cross sections, however, were selected be-

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cause of their greater stability. At all locations,
one or both of the banks are bedrock, and, ex-
cept for the Ouray gage, the bed material is
coarse gravel. The gaged cross sections thus can-
not be considered typical of the channel in allu-
vial, self-formed reaches. .
Aerial and terrestrial photographs are the
primary sources of information from which the
hydraulic adjustment of Green River can be re-
constructed. Large-scale aerial photographs of

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- PRE.RESERVOIR
--- POST.HESERVOIR

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0.050.1 0.5 1 2 5 10 20 30 40 so 60 70 80 90 95 98 99 99.899.9

DURATION OF DISCHARGE 1% TIME)

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some reaches of the Green River downstream
from Flaming Gorge Dam were ta~en prior to
1962 and after 1980. Thus, it is po~ible to in-
vestigate some of the channel chan~b resulting
from flow regulation over - 20 yr. AIUtough aer-
ial photographs do not provide 4 complete
description of the bankfull-channel fharacteris-
tics, several attributes can be measu~ed and de-
duced, especially when combined I with field
inspection. (1) Bankfull-channel width and the
1

. PRE-RESERVOIR
f4:J POST-RESERVOIR

Figure 7. Comparison of the duration for daily mean discharges
during the pre- and post-reservoir periods measured at the Green
River at Green River, Utah, gage.

:
Figure 8. Comparison of the quantity of bed material ~rted by
increments of discharge during the pre- and post-reservo~r periods
computed for the Green River through the Browns Park r~ch.
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