Peak discharges are measured at a limited number of locations (i.e., gaging stations) in Oregon. At unmeasured sites, peak discharges are estimated. In either case, the peaks are reported for recurrence intervals of 2, 5, 10, 20, 25, 50, 100, and 500 years.
Peak discharge estimates require knowledge of several physical characteristics of the watershed of interest (e.g., area, average slope). All estimated peak discharges reported here represent stream flow unaffected by significant reservoir operations, diversions or urbanization. Tools developed as a result of the study allow for the estimation of peak discharges at specified frequencies at most locations on most rural, unregulated streams in Oregon. It is the intent of the Oregon Water Resources Department that information regarding peak discharges generated by the tools provided here be evaluated and used by a qualified hydrologist familiar with the analysis and estimation of peak discharges.
For more information regarding the data and their sources, the user is encouraged to read the accompanying reports for western and eastern Oregon.