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Show APPENDIX VI VI-29 24 COLORADO H1VER STOHAGK PROJECT EXPLANATION OK til LET 2 OF 3 Column* (2), (3), (4), and (5): Actual reservoir storage content, Lake Powell, Flaming Gorge, Cunscatlli units, and Navaho. Values for each of these columns are the actual end of month reservoir surface storage content plus an estimate of initial accumulation of bank storage. Columns (G), (7), (8), and (9): Reservoir storage change-Lake Powell, Flaming Gorge, Curecanti units and Navaho. Values in these columns are derived from figures in columns (2), (3), (4), and (5). Column (10): Actual flow of Colorado River at Grand Canyon. Flow of Colo; rado River measured by, and data reported by Geological Survey. Column (11): Theoretical flow of Colorado River at Grand Canyon. This is computed iis the sum of columns (G) through (10). It is the actual flow of the Colorado River at Grand Canyon increased by reservoir storage changes (algebraic) in the Colorado River storage project reservoirs. Column (12): Computation of theoretical total net loss from Lake Mead, actual total net loss. This is a water budget computation using the measured flow at Grand Canyon as inflow to Lake Mead, the actual release from Hoover Dam and the actual measured storage change in Lake Mead. It includes unmeasured inflow to the river and lake below the Grand Canyon gaging station, evaporation loss from the lake, changes in bank storage, and diversions from the lake to Nevada. Column (13): Computation of theoretical total net loss from Lake Mead- adjustment of evaporation loss. This is an adjustment to be applied to the actual total net loss (col. 12) and is the difference (theoretical minus actual) between the theoretical evaporation for the theoretical surface area of the lake which corresponds to the elevation shown in column (9) of sheet 3 and the evaporation computed by the Geological Survey for the actual surface area of the lake. The evaporation rate applied to the theoretical surface area of the lake is the same rate applied by the Geological Survey to the actual surface area. Column (14): Computation of theoretical total net loss from Lake Mead- theoretical total net loss. Column (12) plus (algebraic) column (13). |