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C"": .~ "'" o independent measurements, can be calculated. Standard methods have been developed to evaluate this net uncertainty. The method developed by Kline and McClintock (1953)* was used in this analysis. The functional relationship between flow and measured variables in this case is expressed as Manning's Equation: Q = 1.49 n -1 A 5/3 Pw -2/3 S 1/2, where Q is discharge (l3 r1). n is Manning's On" (-), A is area (l2), Pw is wetted perimeter (l), and S is slope (l l-\ Because On" is not a measured vaiue, a separate uncertainty analysis was conducted for 'n" to provide an error estimate for use in this analysis. For the sensitivity analysis 01 maximum flow, the following error terms were used: o area and wetted perimeter .:t. 10 percent o Manning's On" .:t. 20 percent o slope.:t. 0.001. The results ofthese anaiyses are shown in the last column of Table 4. TABL.E 4 GURLEY INTAKE DITCH MAXIMUM CAPACITY SENSITIVITY ANAL.YSIS Range with Estimated Maximum Range Probable Capacity .:t.l0% Uncertainty location (cIs) (cIs) (cIs) D/S East Beaver 85 76-94 59 -111 U /S Craver Creek 225 203 - 248 137 - 310 Bwtn Craver & W. Beaver 220 198 - 242 156 - 278 D /S West Beaver 360 324 - 396 256 - 460 Gurley Ditch 745 671 - 820 541-944 A more extensive program 01 flow measurements, surveying, and hydraulic modeling would be required to better define and further reline the ditch capacity estimates. For the purposes of this study, however, no further work is felt to be warranted. The data gathered indicate that the 400 cfs ditch capacity above the chute and the 600 cfs capacity below the chute reported are acceptable values. Given the uncertainty associated with the calculated capacities, there is not sufficient evidence to reject or modify these values. " Kline, S.J. and FA McClintock, 1953. Describing uncertainties in single-sample experiments. Mech. Eng. 75:3-8. 8