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<br />-18- <br /> <br />non-growing season when there was little or no evapotrans- <br /> <br />pi ration the elevation of the water taole rose rapidly. <br /> <br />Conversely, during the growing season, the elevation of the <br />water table diminished. By extrapolating the average rate <br /> <br />of rise during the non-growing season throughout the grow- <br />ing season and correcting for the change in water table <br />elevation at the end of the growing season, the annual and <br /> <br />average annual net rises were determined. The net rise re- <br /> <br />presented the depth of soil from which water was removed <br /> <br />by evapotranspiration. <br /> <br />In order to convert the net rise to an equivalent <br /> <br />quantity of water, the U.S.B.R. in its studies multiplied <br /> <br />the net rise by a so-called "saturation index" which was <br /> <br />equal to porosity minus a wi 1 ting percentage. Our objec,tion <br /> <br />to the use of this formula is the high potential for error <br /> <br />in the determination of either value, i.e., an assumption <br /> <br />of 25% in the value of the "saturation index" rather than <br /> <br />an actual 20% could introduce an error of 25% in the t9tal <br /> <br />quantity of water that would be available for salvage. <br />There appear to be approximately 200,000 acres of land <br /> <br />from which water could be salvaged by lowering the water <br />table and otherwise reducing evapotranspiration opportuni- <br /> <br />ties. The Bureau of Reclamation in its report proposed to <br /> <br />limit the salvage area to approximately 108,600 acres in <br /> <br />order to minimize the impact of lowering the water table on <br /> <br />the adjoining economic productive lands. This initial <br /> <br />f,., r' 4 ""I <br />,..IV\'; U.;.. <br />