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DISCUSSION Data Collection Records of peak floodflows from thousands of sites in the 48 conterminous states are available, Previous studies, such as Alvord and Burdick, 1918 [10]; Barrows, 1948 [11]; Hoyt, 1955 [1); Chow, 1965 112]; and Crippen and Bue, 1977 113], attempted to select the maximums of this vast resource of data for the United States. In the initial phase of this study, it was noted that many Significant flood events have occurred since 1974, and in many cases these events exceeded the maximums previously published for certain streams. The initial data collection phase of this study consisted of selecting maximums from the previous studies and consulting with other Federal and State agencies for updated flood information, with particular interest in the 1 974.1984 penod, The Corps of Engineers provided much valuable data through reports from each of their division and district offices, The USGS (U,S, Geological Survey) also provided excellent assistance by providing records of some historic events that represented large flood events but had little readily available background data. USBR records were also searched, Through the years, the USBR has attempted to maintain lists of flood peaks and volumes for use in drawing envelope curves to compare with design flood peaks and volumes at numerous damsites, For this study only those points that defined the locations of these envelope curves were selected Additional information was obtained through contacts with the USSR's regional hydrology staffs, Many State highway departments, in cooperation with the USGS, have produced reports related to defining maximum discharges within their borders [14, 15, 16], These reports were consulted in areas where significant flood peaks documented in other sources were scarce. Additional sources, such as TVA (Tennessee Valley Authority) reports and papers presented in conferences on floods, also provided significant information, The initial data collection resulted in approximately 600 flood peaks, which are listed in appendix 1, This list contains the most significant events from the sources listed and a number of more recent events from the September 1 974 to September 1984 time period, which were not covered in any previous nationwide collections. This list is limited to flood peaks that had little or no snowmelt contribution, Drainage basin sizes range from 0.1 to more than 42,000 ml2, The long list of flood peaks was reviewed, and those points that appeared to represent a potentlallv large percentage of the PMF were selected for further study, Floods from contnbuling drainage basins larger than 5,000 mi' were not considered because in these cases many more complex factors, such as major upstream impoundments, are often involved in the histonc flood peaks and in determining new PMF values, In addition to the Initial flood peaks listed, four other outstanding peaks from small drainage areas in Virginia were considered These peaks are listed in table 3 and are the result of exceptional Iv Intense rainfall during HUrricane Camile In 1969 117), 8 , ,,-