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. Willow Creek were obtained from the reproduction of the 11 August 1967 flood in Willow Creek as shown on Plate 14. The Willow Creek watershed is very similar to the Fountain Creek watershed and is representative of other basins in the Arksnsas River bnsin above John Martin Dam. Pertinent unit hydror,raph data and dra:lnl1p.e b:l!dn delineations are shown on Plate 15. . 32. INITIAL LOSSES AND INFILTRATION RATES. Rainfall losses were obtained from previous studies done for the ArkanGas River basin. These are contained in the minutes of a conference helel in the Albuquerque District on 29-30 Septemher and 1 Octoher 19(,<1. The purpose of that conference was to discuss the hydrology for the Arkansas River subbasin above Great Bend, Kansas, and WAS attended by District, Division and OCE personnel. Table 2 is a snmmary of the initial and average hourly losses presented at the conference. An initial loss of 1.2 inches and an average hourly loss of 0.49 inch were used for the Fountain Creek watershed. For the Arkansas River from Pueblo to Las Animas, an initial loss of 1.1 inches and an average hourly loss of 0.26 inch were adopted for use and are average values from Table 2. . . 33. STANDARD PROJECT STORM. Standarel project rainfall amounts were obtained from Draft Hydrometeoro10gical Report (mfR) No. 51. An isohyetal storm pattern was prepared for areas larger than 200 square miles and centered critically over the basin under investigation. Standard project rainfall amounts were taken as 50 percent of the PMI'. The 6-hour rainfall amounts were distrihuted in accordance with letter SWlJED-XW aub.1ect: "Maximum Six-Hour Rainfall Distribution of the Standard Project and Probable Maximum Storms," dated 15 February 1974. . . 34. STANDARD PROJECT FLOODS. Standard project floods were de- veloped by applying standard project excess rainfall to the basins' unit hydrograph. The SPF for Fountain Creek has a peak discharge of 152,000 c.f.s. and a volume of 128,000 acre-feet as shown on Plate 16. The standard project floods for the Arkansas River at the dif- ferent locations were developed by critically center:lnr an isohyetal storm pattern above each location. The resultant flood hydror,raphs for each major tributary were then routed to the des:l.red location and combined to yield the SPF at that part:lcular point. Stnndarel project flood peaks for the Arkansas River are tahulated in Table 3. The critical centering of each standard project storm for the Arkan- sas River along with rainfall and fJ ood hydror,raphs are shown on Plates 17 through 71. . . .' 35. PROBABLE MAXIMUM PRECIPITATION. Prohah1e maximum rainfall amounts for Fountain Dam and Reservoir were obtained from Draft Hydrometeorologica1 Report No. 51. An isohyeta1 storm pattern was prepared and centered critically over the dam site. PMI' amounts were reduced as recommended in letter ENGCW-EY subject: "Hop Brook Dam and Reservoir, Hop Brook, Housat~c River Basin, Connecticnt, . . 13 .