WSP05499

• File Number: 8200.766
• Description: Gunnison River General
• State: CO
• Basin: Gunnison
• Water Division: 4
• Date: 4/1/1997
• Author: Mueller and Hiebert
• Title: Assessment of Kokanee Salmon Transport through Blue Mesa Powerplant - Colorado - During the Spring and Summer of 1994-1996
• Water Supply Pro - Doc Type: Report/Study

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Recommended and Actual Hydrological Flow Data
Gunnison River near Grand Junction, Colorado
Water Years 1991 - 1994

Thousands
14

12

10

8

6

4

2

o
Oct Nov Dee Jan Feb Mar Apr May Jun JuJ Aug Sep

1-1991 -1992 -1993 -1994 --.Max -MinI

U.S.G.S_ Water Resources Data, Colorado.

Figure 17. Recommended and actual hydrological Flow Data for the
Gunnison River near Grand Junction, Colorado for water years 1991-
1994.

Based on sampling results we can report on actual fish losses which
occurred during the study and venture an educated guess on what losses
might occur under other operational scenarios. However, the task of
determining at what point measured losses become "significant,"
becomes extremely subjective and well beyond the scope of this study.
More in-depth and longer studies are required to accurately address
that question.

While we accept the assumption that additional fish should be
transported in higher spring/summer releases, we can't dismiss the
notion that these losses could occur anyway in the winter. Normally
fish move to the deeper basins during the winter which is dependent
upon reservoir elevation. This could make them more vulnerable to
transport if they should congregate in the deep intake channel area.
However, the low volume of water released during the winter could make
seasonal variability in transport rates insignificant. If the winter
transport rate were similar to spring/summer's, the overall annual

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