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-Flow frequency analyses are provided here to determine how often flows of different magnitude occurred in historical vs. modern times. The flow. record is broken down-into two groups; -group one is the water years 1914 to 195$ (39 .years of record), and group two is the-water years -19.59 to 1993 (34 years. of record). -The frequency of years with-less-than 20-days of average daily flows equal to or exceeding 10,000 cfs is once every 13 years in the early period vs..once- every 5.7-years-for the -later period (Table 1). The frequency of water years with 5 or more -days with mean flows equal to or greater than 40,000 cfs was once - every 1.86-years in the, early period vs. once every 8.5 years in -the more recent period. Similar patterns are illustrated when looking at the frequency of flows equal to or exceeding 50,000 and 60-,000 cfs. Table 1. Number of days-per year, $ time of occurrence, and frequency of occurrence of years with mean flows greater than 10,000 cfs. n yrs n yr ~ yr fr yr n yr ~ yr fr yr Period record <20d <20d <20d <40d <40d <40d 1914- 39 3 8 1/13 4 10 1/10 1958 .1959- 34 6 18 1/5.7 14 41 1/2.4_ -1993 * n yrs = number of years of record at Cisco gauge. * n yr <20d =number of years with less-than 20 days with >10,000 cfs average flow. * ~ yr <20d =percentage of years with-less-than 20 days with->10,000-cfs average ..flow. * fr yr <20d = frequency of years with less than 20 days with >10,000 cfs average flow. * n yr <40d =number of years with less-than 40-days .with >10,000 cfs average flow. * ~ yr <40d =percentage of years with less than 40 -days with >10,000 cfs average flow. * fr yr <40d = frequency of years with less than 40 days with >10,000 cfs- average flow. 18