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Show HUNGRY HORSE PREDICTION 57 point out the dangers inherent in a project plan based on such averages. He told the large audience: 69 "When the Colorado River Compact was entered into in 1922, it was assumed from past records of runoff that there would be a considerable surplus of water remain- ing after consumptive uses of 7,500,000 acre-feet per year in the Upper Basin and 8,500,000 acre-feet per year in the Lower Basin. "It is now evident that the states of Colorado, Wyoming, Utah and New Mexico in the Upper Basin may physically be limited to depletion aggregating about 6,200,000 acre-feet per year and that even to have provided this yield would have required im- pounding all floods from 1927 to the present time. This reduction in the available supply has been due to the fact that the discharge of the Colorado River at Lee's Ferry [dividing line between Upper and Lower Basins], near the head of Grand Canyon, has averaged only 11,700,000 acre-feet per year since 1930, as compared to an average of 15,900,000 acre-feet per year during the seventeen years preceding. "The situation is no less serious in the Lower Basin. Some projects have been built and plans have been prepared for others in anticipation of about 9,000,000 acre-feet of water per year being available from the Colorado River below Hoover Dam, exclusive of any contribution from the Gila River, which is almost wholly consumed in Southern Arizona. "However, when the Upper Basin states deplete the flow of the Colorado River to the extent to which they are entitled, and probably long before that time, there will be available to the lowest reservoir on the Colorado River, only 7,000,000 acre-feet per year to satisfy |