Laserfiche WebLink
<br />. . ~ <br /> <br />Upper Basin Depletions <br />In the studies Upper Basin depletions are measured at Lee Ferry and <br />include changes in storage at water use project reservoirs. <br /> <br />Two different Upper Basin depletion schedules were considered. One <br /> <br />was submitted in our initial draft of data handed out at the Denver <br /> <br />meeting and represented the Bureau's estimate of the timing and magnitude <br /> <br />of depletions which will occur in the Upper Basin. (Base Depletion). <br /> <br />The second represents the estimates of the individual Upper Basin States <br /> <br /> <br />and the Upper Colorado River Commission. The graph (Figure 1) shows <br /> <br /> <br />Upper Basin depletions for both estimates. (Rapid Depletion). <br /> <br />In addition, we have related the year-by-year depletion to the stream- <br /> <br />flow for the year by using a somewhat smaller than normal depletion in <br /> <br />below average runoff years and a higher than normal in years of above <br /> <br />average runoff. Our calculations and assumptions for these estimates were <br />furnished you previously. The graphs (Figures 2, 3, 4, ~d 5) depict the <br />total and normal additional year-by-year depletion and the total and addi- <br />tional year-by-year depletion associated with two specific sequences (Nos. 6 <br /> <br />and 12) for both the base rate and the rapid rate of depletion. <br /> <br />As with differing sequences of streamflow, variations in the two Upper Basin <br />depletions show significant ranges of values of energy production, terminal <br /> <br />storage, and Lower Basin uses and waste as shown in Table 3 (2 Sheets). <br /> <br />The comparison in Table 3 shows that a more rapid rate of depletion in the <br />Upper Basin will reduce water and power available in the Lower Basin and power <br /> <br />in the Upper Basin. <br /> <br />12 <br />