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Table 5 Lone Pine Creek Discharge-Probability Relationships . Drainage Flood Ststion Area 10-Year 50-Year 10,O-Year 500-Year (sq. Ill!.) (c.Ls. ) (c.Ls. ) (c.f.s.) (c.Ls.) u/S from South Lone Pine Creek 38 550 1,500 2,120 4,180 Dls from South Lone Pine Creek 65 920 2,570 3,660 7,230 u/S frolll Right-Rank Tributary 74 1,040 2,860 4,080 8,080 DIS frolll Right-Bank Tributary 78 1,130 3,070 4,380 8,620 Mouth 87 1,260 3,380 4,810 9,510 TRIBUTARIES AT POUDRE PARK Results of the hydrologic portion of a special study at Poudre Psrk, Colo~ado, are presented in this report. Discharges for the 10-, 50-, 100-, and 500-year floods are given in table 6 for tributaries of the Cac~a la Poudre River at Poudre Park. Data for the Cache la Poudre River have been presented in preceding sections of this report. Hill Gulch and Falls Gulch are right-bank tributaries draining a total of about 7 sq'lare miles. Hewlett Gulch is a left-bank tributary with a drainage area of about 23 square miles. Figure 4 is a map of the Poudre Park vicinity. Peak discharges generated from the Cache la Poudre River tribu- taries at Poudre Park were assumed to be noncoincident with the Cache la Poudre River flood discharges. In order to maintain continuity with the Cache la Poudre River rainfall values, 6-hour storms were applied to the watersheds of Hill Gulch, Falls Gulch, and Hewlett Gulch. Small areas are generally the most sensitive to short duration storms, but storm duration is not reflected in the SCS curve number method. The SCS National Engineering Handbook, Notice 4-102, August 1972, page 18 .