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1916-1980 1916-1983 Station Skew G ~ -.7 597 609 l7A Weighted Skew G - -.3 697 694 17B Weighted Skew G = -.5 637 648 I I I I I I I I I I I I I I I I I may have been rainfall on top of runoff since the baseflow is part of a diurnal pattern that continues for two weeks after the peak flow event. The other (June, 1938 - Fraser) is the lowest peak flow examined. Two of the strip charts from the Vasquez (June, 1938 and June, 1965) show a steep vertical rise in stage over a very short time, followed by a high base flow for several days and then a sharp drop in stage. This is probably caused by operation of the diversions on this stream. Analysis using Bulletin l7-B and Flow Data through 1983 Since Worrall's Study was completed in early 1981, it did not use the most current WRC Guidelines for Determining Flood Frequency (17B, September, 1981). In addition, flood flows in the years since the study was completed (1981, 82, and 83) have been significantly high. For instance, the 27 June, 1983 peak flow of 618 cfs on the Fraser River at Winter Park is the second highest flow of record. the highest being 820 cfs on 13 June, 1983. To determine if these changed conditions would affect the results significantly, one of the eight gaging station I s data were analyzed us ing flow data through 1983 and 17B procedures. The 100-year peak flows for the Fraser River station calculated in the various procedures are summarized in Table 5. TABLE 5 100-year Flows (cfs) , Fraser River - Station 09024000 Using 17B instead of 17A weighting procedure, the peak flows were reduced 6 to 7 percent. It is interesting to note that the 17B -6-