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e e ei ., estimated at 10,000 cfs. The highest snowmelt peak at Dolores, 8,070 cfs, was recorded in May 1941. In June 1949 a general rain on the snowpack produced an even higher peak at Dolores, ; 8,140 cfs. For the 50 years of record at the Rico gage, the highest snowmelt peak, 2,170 cfs, was recorded May 1984; the highest rainflood peak, 1,930 cfs, recorded September 1970. Most of the annual rainflood peaks were small events. Due to the scarcity of large rainflood peaks, the rain on snow events were included in the record for analysis. 8.3 Flood Frequency Analysis. The HEC Flood Frequency Analysis (FF A) computer program (see Reference 4-k) was used to apply Water Resource ~ouncil Guidelines to the statistical analysis (See Reference 4-m). The annual snowmelt and rainflood duration data were analyzed separately using the FF A program. The snowmelt flows for Dolores River at Dolores were analyzed for peak, 1-,3-, 7-, 15-,30-,60-, and 90-day durations. For Dolores River below Rico gage, the snowmelt season is shorter; the 60- and 90-day durations were not considered. The rainflood flows were analyzed for the 1-,3-, 7-, 15-, and 30-day durations, since the impact of rain on snowpack runoff does not last longer than a month. Too many annual rainflood peak flows are missing from the records for Rico and Dolores to allow for any meaningful statistical analysis, so the FFA program was not used for the rainflood peaks. The FF A program did not identify any high or low outlier rainfloods for the Rico and Dolores gages. For the snowmelt records, FFA analysis identified 1977 and 2002 as low outlier years at both Rico and Dolores; 1990 and 2002 were low outlier years at the Lost Canyon Creek gage. The annual flow duration data for Rico and Dolores were analyzed as database sets for rainflood and snowmelt separately for each gage. The HEC-Regional Frequency Computation Program (REGFQ, see Reference 4-f) was used to analyze the duration data sets, to smooth the 31