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For 0.50<A~< 3.00: -10 QI0= 500 0.89 (5 =41.1, R=0.96) ( 12) AE e Q25= 84M 0.97 (5 =40,1, R=0.98) (13) E e Q50=1 ,140AE 1. 01 (5 =40.2, R=0.99) (14) e QI00=1 ,550AE1 .07 (5 =34.0, R=0.99+) (15 ) e For 3.00~AE ~15.0: QI0= 830A 0.41 (5 =48.6, R=0.61) (16) E e Q =1 560A 0.44 (5 =39.8, R=0.70) (17) 25' E e Q =2 280A 0.47 (5 =35.4, R=0.78) (18) 50' E e Q =2 930A 0.50 (5 =29.7, R=0.84) (19) '100' E e On the basis of the statistical measures (5 and R) of the ability of these equations to predict the flood characteristics, th~se regionalized equations should provide better overall estimates than equations 8 to 11. As previously mentioned, further regionalization of these data could not be accomplished because of the lost degrees of freedom in the statistical analysis. However, an analysis of stations in the South Platte River basin is currently underway and may provide sufficient additional information to refine these relationships or justify further regionaliza- tion of regression results (D. R. Minges, U.S. Geological Survey, oral commun., 1980) . l The results of the multiple-regression analysis for the regionalized 100-year flood discharge (equations 15 and 19) for drainage areas from 0.5 to 15 mi' are shown in figure 6. Also shown are the weighted values for QI00 at the 15 stations used in the analysis, the recorded peak discharges for 34 miscellaneous small watersheds in the region (table 7), the maximum potential flood flow in the region (Crippen and Sue, 1977), and the estimated QI00 relation for the plains region of Colorado given by McCain and Jarrett (1976) for a basin slope of 115 ft/mi. The results of the station-year method and the 28 nonstudy stations will be discussed in later sections of this report. The maximum potential flood is, of course, considerably higher than the regression relations given by equations 15 and 19. The relation developed by McCain and Jarrett (1976) gener- ally is in close agreement with the regression results, except for drainage areas less than about 2 mi' where their estimates of peak discharge are as much as 100 percent higher for a 1 mi' basin. Figure 6 shows frequency of occurrence for about 14 of the 34 floods on miscellaneous watersheds was greater than 100 years according to equations 15 and 19. 21