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during subbasin delineation in the Geo-HMS process (see Appendix A, Table 4). Unit e hydro graph parameters for the subbasins are listed on Table 7. Table 7 Unit Hydrogral)h Parameters Basin I D.A. I L I Lea I Slope I "n" Lag Name (mi2) (mi) (mi) (ft/mi) (hrs) West Fork Dolores 168.41 33.85 16.58 139.13 0.16 16.66 Dolores Headwaters 105.33 21.22 9.38 151.42 0.16 11.06 Dolores Upper Mid 65.32 15.11 6.89 232.25 0.16 7.97 Bear Creek 33.63 15.12 7.43 191.00 0.16 8.51 Dolores Mid 74.25 20.99 9.09 201.55 0.16 10.31 Dolores Lower 57.34 19.78 9.39 105.21 0.16 11.09 Lost Canyon Creek 74.06 27.74 14.71 128.64 0.16 14.98 Lost Canyon Creek Out 3.43 5.34 2.38 105.29 0.16 4.16 Dolores Out 0.57 1.85 1.07 219.16 0.16 1.79 Dolores Lower Out 0.53 2.06 1.24 165.73 0.16 2.08 ---..-----------.------------- D.A = drainage area in mi2 L = length along the longest watercourse in miles. Lea = length along the longest watercourse, measured upstream to the point opposite the center of the area in miles. Slope = overall slope of the longest watercourse between the headwater and collection point in feet per mile. n = coefficient representing basin roughness and shape. _ Lag = elapsed time from the beginning of unit precipitation to the instant that the S-curve reaches 50 percent _ of ultimate discharge in hours.- Refer to Plate 7 for S-Curve and Plate 8 for Lag Relationship 6.7 Stream Routing Parameters. The hydro graph at each junction was routed to the next downstream junction and combined with the local subbasin hydro graphs. The length of each routing reach between junctions was calculated using topographic maps. Junction elevations were provided by USGS streamflow gaging station records or were determined from the examination of terrain maps to calculate slopes for the routing reaches. Routing reach elevations and slopes are listed on Table 8. -- 20