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

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CALIFORNIA DEFENDANTS Exhibit No. 1241 Identification: .................... Admitted: July 12, 1957 Extract From llnsley, kohler and paulhus, applied hydrology (1st ed. 1949) (p. 175) Consumptive Use and Total Evaporation The hydrologist studying the hydrologic balance for a given area or basin is less concerned with the magnitudes of the individual elements such as transpiration and soil evaporation than with their total. Total evaporation, or evapo-transpiration, is considered to include all water losses from a given area by transpiration and by evaporation from water surfaces, soil, snow, ice, and vegetation. The term consumptive use3 has been widely used by irrigation engineers to describe the total amount of water taken up by vegetation for transpiration or building of plant tissue plus the evaporation of soil moisture, snow, or intercepted precipitation. The duty of water, as used in irrigation work, describes the total volume of water required to mature a crop, including, in addition to consumptive use, the water lost by evaporation from canals and ditches and the water eventually returned to the streams by percolation or surface runoff. All terms are expressed in units of depth (feet or inches) for a specified period, usually a growing season or water year. 3"The Rio Grande Joint Investigation in the Upper Rio Grande Basin," Vol. 1, National Resources Committee, Washington, D. C, 1938.