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This effect is also shown on Fi ure 3.14 which de icts the Colorado River cross-section (at the g P Palisade gage) and what the effects on low year and high year average flows would have been at the i top of the 15-mile reach. The change in stage due to future District diversions is difficult to visualize, even with the distorted vertical scale. 3.3.5 1 S-Mile Reach Flow Effects (Make-up Flows) 3.3.5.1 Comparison to Target Flows The USFWS (1995) has recommended both mean monthly and peak flows required to maintain the habitat for endangered fish species within the 15-mile reach. The results of the analysis discussed above can be directly compared to the recommended monthly flows. It is not possible to compare the results to daily peak flows because increments of less than one month are not feasible in the Ute Water operations model, which is based on historical monthly hydrology. Figure 3.15 presents 12 monthly frequency distribution graphs of the USFWS recommendations ~` compared to the historic (adjusted for Section 7 consultations) and projected future flows at the top of the 15-mile reach (the last page of the figure provides some guidance on interpreting the graphs). The graphs show the effect of future District diversions on Colorado River flows, with the visible offset of the Future line from the Existing line. These graphs may be easily interpreted by comparing the historic and future lines to the USFWS recommendation lines. At any given percentage, where historic and/or future flows are greater than (to the right of) the recommendations, the recommendations are being met; where flows are less than (to the left of) the recommendations, the recommendations are not being met. In November through March, the 50 percent and lower recommendations will nearly always be met, but the 80 percent and 100 percent recommendations are not currently being met and most certainly will not be met under future conditions. The only way the November through March 80 and 100 percent recommendations could be met would be by decreasing current diversions by all Colorado River Basin water users. During the snowmelt and high runoff season (April through July) and the low flow summer period (August through October), the difference between the flow recommenda- tions and both the historic and future flows is significant, with none of the recommendations being met at any time under current or future conditions. It is apparent that the District's future operations could not provide a means of meeting the USFWS recommendations, even if future project diversions. were reduced to zero. 3.3.5.2 Make-up Flow Calculations During the informal Section 7 consultation with the USFWS, a methodology was developed to quantitatively measure the project flow reductions against the USFWS target flows and to calculate the amount of water which would be needed to eliminate the effect of such flow reductions on the targets. The evaluation was conducted under six separate population projections, corresponding to the future demands for the years 2000, 2005, 2006, 2010, 2015, and 2045. This was done to show the manner in which impacts are expected to grow over the next 20 years in addition to the impacts expected over the life of the project. CDM Camp Dresser & McKee 0:8047-IIO~DOCW'PEND-B.DOC B-16