OCR Text |
Show -10- that the running average reached 14,000,000 acre feet annual discharge, 13 years after the minimum of 1954, and that again, after eighteen years more, the average was 14,000,000. That would be about 1985 counting toward the future. And, from that time, during the balance of the 60-year period, it continued to rise for many years, and in the last ten years did not fall below 15,000,000 acre feet which it might have reached after forty years, that is, about 1995. The first thirty years and the last thirty years of this discharge record can be regarded as samples from the same universe, speaking in statistical terms. The last thirty-year sample represents a period of very reliable records. The first sample of thirty years may be given equal credence for the sake of discussion. The average discharge for the period from 1896 through 1925 was 16,650,000 acre feet. The average discharge for the second sample, from 1926 through 1955, is 13,850,000 acre feet. What would the Compact of 1922 have provided in case that Commission had only the last thirty years' records at Lee Ferry to consider instead of the first thirty years' records? Obviously, that difference of 2,800,000 acre feet in these two thirty-year averages would have made very significant differences in the firm figures that were used in the Compact. Ordinarily, especially in the more humid eastern and mid-western areas, a series of twenty-five to thirty years of continuous records is considered to be sufficient to determine a reliable mean since the fluctuations of annual stream flow are much less east of the 100th meridian. However, that is not the case in the arid west, especially in the inter-mountain region. Finally, in this connec- |
Source |
Original book: [State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California, defendants, United States of America, State of Nevada, State of New Mexico, State of Utah, interveners] : |