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Daily gaged or synthesized flows first were expressed as a percentage of monthly flows: <br />Daily % = Daily cfs gaged or synthesized data) x 100 <br />Monthly sum of all daily cfs values <br />Daily percentages were applied to each monthly CRDSS volumetric value (AF) to arrive at a <br />daily discharges in AF /day, which were converted to cfs as follows: <br />cfs = AF /day x 43,560 cubic feet/AF <br />86,400 seconds /day <br />We calculated the frequency, magnitude and duration of transgressions of an average daily flow <br />target of 93 cfs for each of the four demand scenarios. We defined transgression frequency <br />(transgression -days) as the total number of days each year which failed to meet the flow target. <br />We defined the duration of transgressions as the greatest number of consecutive transgression - <br />days each year and defined the magnitude of transgressions in terms of their "deficit" of the 93 <br />cfs target. We calculated the monthly deficits in AF as the sum of the daily deficits (AF /day) <br />according to the formula: <br />AF /day = (93 - Q cfs) x 86,400 seconds /day <br />43,560 cubic feet/AF <br />Where Q is the estimated average daily flow less than 93 cfs We calculated gross deficits as if <br />93 cfs were a minimum flow. To approximate historic flow conditions, we calculated net deficits <br />by subtracting gross historic deficits from gross 2025 or 2045 deficits. We did not calculate <br />daily surpluses for values of Q > 93 cfs, because surpluses were not used to offset deficits. <br />Results and Discussion <br />Statistically, the 17 years of the CRDSS are normally distributed, with 6 "dry ", 6 "wet" and 5 <br />"normal' years, where "normal' is defined as the mean annual historic discharge ± % standard <br />deviation of the historic discharge of all 17 years. Wet years are those whose discharge is greater <br />than %2 standard deviation above the mean annual historic discharge, while dry years are those <br />whose discharge is greater than %2 standard deviation below the mean annual historic discharge. <br />Nine (53 %) of these years exhibited no transgressions under either natural or historic demand <br />conditions. However, under 2045 demand conditions, 12 years (1975 -81 and 1987 -91) had at <br />least one transgression of 93 cfs during July- October, including all of the dry and normal years, <br />and even one of the wet years (1978). <br />Summaries of daily flow data under natural, historic, 2025 and 2045 demand scenarios for the <br />median year (1975), driest year (1977), wettest year (1984) and the year with the driest low -flow <br />period (1990) at the Maybell gage (Tables 1 -4) above the Maybell Canal diversion (Tables 5 -8). <br />Daily flows were compared to the 93 cfs flow target to calculate frequency, magnitude and <br />duration of transgressions of the flow target. Transgressions are summarized in Tables 1 -8 on <br />both a monthly basis and an annual basis. We also plotted 1975, 1977, 1990 and 1984 annual <br />hydrographs for each of the four demand scenarios at the Maybell gage (Figures 1 -4) and above <br />the canal (Figures 5 -8). Tables 9 -12 summarize total annual transgressions and deficits of the <br />flow target for all 17 years at the gage (Tables 9-1 0) and above the diversion (Tables 11 -12). <br />Appendix B 4 <br />