AZ vs. CA:11 California Exhibits, Vol. XI; Nos. 1001-1011; 1101-1109; 1201-1251; 1301-13431301-1343

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-2- water-consuming areas and the integration method necessitates measuring all of the areas and the amounts of water consumed on each area. Another method of estimating valley consumptive use is to measure the inflow and outflow. Water inflow to a valley includes surface streams, sub-surface ground-water flow, upward ground-water flow resulting from pressure, and precipitation. Water outflow includes surface and subsurface flow and lowering of the ground-water table. The inflow minus the outflow is considered as the amount consumed and is therefore designated the "consumptive use." From 1924 to 1928, the Committee on Irrigation, American Society of Civil Engineers, developed a report on the consumptive use of water, including basic analysis, appropriate equations, methods of evaluating consumptive use, and a resume and analysis of experimental data. In this report, which was published in the Proceedings of the Society of April, 1928, and in its Transactions of 1930 [California Exhibit No. 27], seven basic rational equations for analyses of consumptive use were proposed. These equations include the effect on consumptive use of the available heat, evaporation, soil moisture, the crop, and the yield, together with relations between consumptive use of water on the farm, the irrigation project, and the irrigated valley. . . .