7740

• UCREFRP Catalog Number: 7740
• Author: McAda, C. W. and L. R. Kaeding.
• Title: Physical Changes in the Gunnison and Colorado Rivers Resulting from Construction of the Aspinall Unit and Related Projects, with Hypotheses to Assess the Effects on the Endangered Fishes
• USFW Year: 1991.
• USFW - Doc Type: Final Report.
• Copyright Material: NO

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Table A7. Measured and estimated virgin streamflow for the Gunnison River
near Grand Junction, Colorado, 1952-1983.
Mean-monthly streamflow (CFS)
Measured Flow Estimated Virgin Flow
Years / ------ ------- - - ------- Pe rc e n t
Month Mean Std. Error Mean Std. Error Change
1952-1965
JAN 843.7 29.6 824.0 27.5 + 2.4
FEB 893.9 47.8 861.3 41.3 + 3.8
MAR 971.1 58.2 988.6 - 52.6 - 1.8
APR 2,798.9 480.8 3,335.4 465.6 - 16.1
MAY 6,536.0 1,013.0 8,555.5 1,022.9 - 23.6
JUN 6,986.1 1,301.9 9,367.5 1,364.6 - 25.4
JUL 2,475.7 849.4 3,729.8 870.7 - 33.6
AUG 1,219.9 236.3 2,035.2 270.2 - 40.1
SEP 1,082.5 159.2 1,385.1 166.3 - 21.8
OCT 1,123.6 111.2 1,287.1 106.7 - 12.7
NOV 1,149.4 66.5 1,156.5 66.7 - 0.6
DEC 946.0 49.7 922.7 54.3 + 2.5
1966-1983
JAN. 2,011.1 169.0 964.4 40.4 +108.5
FEB 1,864.2 203.2 897.3 47.2 +107.8
MAR 1,901.8 210.1 1,235.4 86.2 + 53.9
APR 2,441.6 302.8 3,121.8 294.6 - 21.8
MAY 4,793.3 562.5 8,729.9 826.7 - 45.1
JUN 4,439.8 705.6 9,434.6 968.1 - 52.9
JUL 1,991.0 393.7 3,798.4 467.6 - 47.6
AUG 1,351.3 168.0 1,869.4 182.4 - 27.7
SEP 1,611.3 153.1 1,552.8 192.0 + 3.8
OCT 1,726.1 142.9 1,480.9 131.9 + 16.6
NOV 1,902.8 132.2 1,212.7 64.2 + 56.9
DEC 2,153.9 145.6 1,024.4 46.2 +110.3
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