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~ N ~ values and errors in data entry. After reconciliation, the ratios of mean hourly flow to the mean C> daily flow were calculated. This normalizes the data and allows comparison between days with different mean daily streamflow values. Times and magnitudes of the minimum flow and maximum flow were noted and summarized. Table 4 presents the mean and standard deviation of the times and magnitudes of the minimum and maximum hourly flow at each station for the four melt seasons studied. Figure 2 presents the general diurnal patterns for the three stations. The lines in Figure 2 represent a subjective fit through the data. All three stations have the same general sinusoidal shape. The Gurley Ditch station lags approximately three hours and the Beaver Creek station lags approximately two hours behind the West Beaver Creek station. From Table 4 it can be seen that the variability of the maximum flows (in terms of the ratio of maximum flow to mean daily flow) at Beaver Creek and Gurley Ditch is higher than at West Beaver Creek. The flow at both the Beaver Creek and Gurley Ditch stations is the composite of contributions from many tributaries and the operations of several diversions. Only 33 percent of the area which contributes to the flow at Beaver Creek gage is not controlled by diversions to the Gurley collection system. The manipulation of flow by the diversion structures results in higher variability in the downstream flow records. TABLE 4 SUMMARY OF MAXIMUM AND MINIMUM HOURLY STREAMFLOW Minimum Maximum Hour 1) Ratio 2) Hour 1) Ratio 2) West Beaver Creek mean 12.5 .86 20.6 1.17 standard deviation 1.1 .06 1.7 .09 Gurley Ditch mean 15.5 .82 23.5 1.24 standard deviation 1.4 .06 1.5 .16 Beaver Creek mean 15.0 .87 22.7 1.19 standard deviation 2.1 .08 1.4 .19 1) hour of occurrence (for example 15.5 = 3:30 pm) 2) ratio of hourly flow to mean daily flow 4