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

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-10- River Drainage Basin in Wyoming, it is evident that some of these causes of variations are due to extreme differences in elevation, topography and geology as these affect the slope of the terrain and of the streams draining that terrain. There are also variations in climate, particularly as to the amount and distribution of precipitation, also variations in mean temperature, both annual and seasonal. It seems apparent that these factors will greatly influence the rate of run-off per square mile from the regions where most of the irrigation development in the basin is for meadows and pastures as compared with that from lower undeveloped areas and from the settled and irrigated areas themselves. Variations in the consumptive use of water due to the activities of man probably also vary greatly from year to year, due, among other causes, to differences in the availability of water during the ordinary irrigation season. During seasons of short supply, the depletion of stream flow will obviously be less than the depletion during years of average supply. On the other hand, where storage of water for late irrigation is at a minimum, as in the Green River Basin, during seasons of high and excessive run-off, larger quantities of water would be diverted and probably spread over greater areas, especially on meadow and pasture lands with greater consumptive uses. It was found that applying the principles of Debler's method of adjusting for this variation, the inflow-outflow relationship was somewhat improved. The Debler method, it will be recalled, is based on the assumption that consumptive use or stream depletion is greater or less than the normal depletion in the proportion of 3^2 the ratio of the difference between the virgin flow and the average virgin flow,