AZ vs. CA:12 California Exhibits, Vol. XII; Nos. 1350-1383; 1400-1446; 1501-1518; 1601-1603; 1701-1703

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__2__ mittee, which consisted of lawyers and engineers, was unable to arrive at any satisfactory way in which to explain or account for what occasionally appeared as a "negative" depletion. While the discussions over this difficulty are interesting and enlightening, they are too long and involved to include in this report. The whole problem was very fully reported and discussed at the special meeting called for that purpose, among others, at Denver, on January 20, 1951. Briefly, when the outflow is so much greater than is indicated by an equation or diagram that, if the recorded outflow is subtracted from the virgin outflow as derived on the basis of the theoretically computed flow, the sign of this difference is negative, then this difference, which is the theoretical man-made depletion, is set down as a "negative depletion." But no wording for a regulation has yet been found which has been sufficiently clear to be satisfactory to the Commission. The explanation is of course that, for that particular year, the unmeasured inflow to the stream between the index stations and the outflow stations is greater than the depletion by the amount of this difference. Examples are shown in the Inflow-Outflow Manual for the year 1941 on Plates 4, 5 and 6 and more glaring examples for 1942 and other years on Plates 10 and 11. Because of the situations briefly outlined above, the investigations for the practical application of the Inflow-Outflow method for the administrative purposes of the Commission has been the effort to reduce such discrepancies to acceptably reasonable amounts by the use of multiple correlation computations. Attention should also be called to the fact that the opposite situation may also occur. For example, an unusually small outflow quantity, when subtracted from the theoretical virgin flow for that year might indicate almost twice normal depletion. The points on Plate 14 of the