Information on high-flow magnitude and frequency is needed for hydrologic evaluation of such factors as flood-control storage and dam safety. High-flow information given in this report is for streamflows unaffected by major regulation, such as by large reservoirs. High-flow magnitude and frequency data are given for 91 streamflow-gaging stations throughout Kansas. Results of frequency calculations are given for durations of high flow of 1, 3, 7, 15, 30, 60, 90, 120, and 183 consecutive days. Accuracy of the magnitude-frequency values is influenced by the variability of flow, the number of years of flow record, and the recurrence interval calculated.
High-flow magnitude and frequency for ungaged sites can be estimated from regression equations using significant drainage-basin characteristics of contributing-drainage area; 50-year, 24-hour rainfall; and free-water-surface evaporation. Standard errors of estimate for ungaged sites on ungaged streams range from 31 to 49 percent, generally increasing with recurrence interval. If an ungaged site is near a gaging station having 10 or more years of record on the same stream, the data for the gaging station may be used to improve the regression estimates.