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<br />. <br /> <br />. <br /> <br />. <br /> <br />, <br /> <br />" <br /> <br />21 <br /> <br />The existing condition simulation reflects the operation of all existing <br />Federal and private projects in the study area. Specifically, the analysis <br />consisted of operating the entire HYDROSS network for the 1952-1982 period <br />with depletion levels on all diversions set to the level they were in the <br />1982-1984 period, or at projected levels for those projects not operating in <br />1982-1984. One difference between these flow conditions and actual Survey <br />9auge data for the period is that each project was operated to its maximum <br />capacity.allowed within the State water rights priority system. Simulation of <br />maximum project operation represents the cumulative effects of future State or <br />private activities that are reasonably certain to occur. <br /> <br />The third level of analysis is a simulation of the environmental baseline. <br />Working from the existing condition development scenario, the environmental <br />baseline was created by imposing the operation studies of all projects which <br />have previously undergone formal Section 7 consultation, but are not yet <br />operating, on the existing condition baseline. Table 8 displays all projects <br />and depletions included in the environmental baseline for the Ruedi Round 11/ <br />Green Mountain analysis. <br /> <br />At the request of Reclamation, the Section 7 analysis of the two sales was <br />combined and treated as one project. The Ruedi Round II/Green Mountain <br />ana 1 ys is was accompli shed by impos ing Ruedi Round II and Green Mounta in water <br />sale depletions onto the environmental baseline. The hydrology input to the <br />hydrology simulation model was then modified to reflect the operation of Ruedi <br />and Green Mountain reservoirs at the mouth of the Roaring Fork and at Dotsero. <br />The hydrology simulation model was then used to produce post-project <br />conditions at seven locations in the Upper Colorado River Basin. <br /> <br />RESULTS <br /> <br />The effects of the Ruedi Round II and Green Mountain water sales both with and <br />without the conservation measures were statistically evaluated. Three years <br />were selected to represent the 20, 50, and 80 percentile flows over the 1952- <br />82 study period. <br /> <br />Percent il e Flow <br />20 <br />50 <br />80 <br /> <br />Water Year <br />dry <br />average <br />wet <br /> <br />Selected Years <br />1955, 1961, 1966 <br />1953, 1969, 1982 <br />1970, 1973, 1979 <br /> <br />Monthly flow values for the years were averaged to normalize the values. The <br />normalized values were used to compare flows between the different levels of <br />development (e.g. historic, present level, environmental baseline). The three <br />types of water years (dry, average, wet) were then evaluated by selecting and <br />comparing flows corresponding to the appropriate years and months from the <br />historic, existing condition, environmental baseline and Ruedi II/Green <br />Mountain simulations. <br /> <br />The comparison of flows at the Palisade habitat site are displayed in both <br />thousand acre-feet (KAF) and cfs in Tables 9 and 10. Flow increases to <br />reaches modeled between historic.and existing conditions can be attributed to <br />the construction and operation of large reservoirs in upstream areas. These <br />