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7.6 1 % Flood Hydrographs. The calibrated HMS model was used with the 1 % 48-hour - storms, loss rates, baseflow, unit hydro graph parameters and Muskingum routing parameters discussed above to develop 1 % flood hydro graphs on the upper Dolores River basin. Peak flows for the 1 % West and East Fork centerings, output from the HMS model, are listed on Table 14 for several locations. The difference in 1 % flood peak flows at Dolores between the East and West fork centerings is not significant; however, the East Fork centering produced a peak flow at the below Rico gage that is much higher than indicatc:::d from the flow frequency analysis for the Rico gage. This is discussed further in Section 8, Flow Frequency Analysis. For the 1 % flood hydro graph for the Dolores River below Lost Canyon Creek for the West Fork Centering see Plate 26. Table 14 Peak Flow (cfs), 1 % ]~xceede:nce 2-day General Storm West Fork vs. East Fork Centering Index D.A. West Fork Centerings East Fork Centerings Point (me) Peaks (cfs) Peaks (cfs) "upper rnainstem" Dolores R below Rico 105 2,290 5,260 Bear Creek 34 1,130 1,010 East Dolores above West Fork 278 7,516 8,233 West Dolores at mouth 168 3,820 3,580 East Dolores plus West Fork 446 11,300 11,600 Dolores at Dolores 504 11,700 12,000 Lost Canyon Creek near Dolores 71 820 910 Dolores R below Lost Canyon Creek 579 12,300 12,600 . 8. Flow Frequency Analysis 8.1 Upper Dolores Basin Streamflow Records. The 1976 flood hazard information hydrology report included a peak flow frequency analysis for the West Dolores River at mouth, upper mainstem Dolores River above West Dolores River, Lost Canyon Creek at its mouth, and Dolores River below the confluence with Lost Canyon Creek. An additional 29 years of streamflow records are now available for analysis at the Rico and Dolores gages. The Lost e 28 ,