Flood frequency analysis uses historical flow records to both estimate the frequency with which floods of a certain magnitude may occur and predict the possible flood magnitude over a certain time period. This module offers a thorough introduction to appropriately constructing the necessary historical data series, calculating the flooding probabilities, and gauging the reliability of the resulting probability values. Methods for assessing flood frequency in basins with limited data are also discussed.
Define the meaning of return periods (i.e., the 100-year flood)
Explain the exceedance probability and its relationship to return period
Explain how the period of record impacts flood frequency guidance
Calculate the probability of occurrence for a given flood magnitude over a specified duration
Understand how basin changes may impact the frequency of floods via affecting the period of record
Explain the basic concepts underlying both annual and partial duration time series
Conduct a frequency analysis given the peak flow data for a river
Explain the purpose, applications and limitations of design events
toplevel, hydrology, flood prediction, flood frequency analysis, flood frequency , time distribution of floods, flood magnitude, return period, statistical representation of floods, period of record, exceedance probability, flood data, annual series, annual maximum daily flow, annual series rank, annual series probability, annual series display, partial duration series, partial duration display, design events, probable maximum event, standard project flood, non-exceedance probability, recurrence interval, homogeneous record, independence, urbanization, design storm, design flood, probable maximum precipitation, PMP, probable maximum flood, PMF
October 2020 - The lesson was updated to current internet standards (mp4/html5), with no changes to content.
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