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DeveloRment of Baseline Daily Flows The Fish and Wildlife Service baseline hydrology used in the Stagecoach biological opinion was obtained from the HYDROSS model. The Yampa River below the Little Snake confluence node had mean monthly flow values for the 1930-1982 calender years; to extend the baseline to include mean monthly values through water year 1986, the following steps taken: Mean monthly values for each calender year of the baseline were arranged into water years, providing values for water years 1941-1982. Monthly accretions and depletions between the baseline and historic record were calculated by subtracting the historic monthly mean from the baseline monthly mean, and then averaging each month over the 1941-1982 water year period. This provided 12 mean monthly accretion/depletion values between the historic and baseline conditions. Baseline monthly means for the 1983-1986 water years were then estimated by adding/subtracting the mean monthly accretion/depletion with the historic mean monthly flows. With mean monthly flows for the baseline 1941-1986 water year period, the ratio between the baseline mean monthly flow and the historic mean monthly flow was computed for every month of the 1941-1986 water year period. These are shown in Table 5. A FORTRAN program (Hisratio) multiplied each daily flow value of the Deerlodge Park 'historic' 1941-1986 record by the above ratios, resulting in daily flow values for the baseline condition. Development of With Project Daily Flows W. W. Wheeler & Associates, Inc.(1981) investigated the yield of the Juniper- Cross Mountain water rights for the Nature Conservancy to aid in their negotiations regarding instream flow purposes. The following excerpt from the report describes the adjusted flow at the Yampa River near Maybell gaging station for the project. Streamflow downstream of the Juniper Reservoir was equal to the sum of the flow which could not be stored under the senior Juniper storage decree, direct diversions and reservoir releases for power, and reservoir spills. To obtain the adjusted flow at the Maybell gaging station, the flow downstream of the Juniper Reservoir was further reduced for the required diversions by the senior Maybell Canal water right. If the Maybell Canal water right was not completely satisfied, direct irrigation diversions for the Deadman Bench Canal were reduced to the extent the Maybell Canal was not satisfied or direct diversions for the Deadman Bench Canal were not allowed.