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PeakFQ

October 28, 2024

The PeakFQ software implements the Bulletin 17C procedures for flood-frequency analysis of streamflow records, providing estimates of flood magnitudes and their corresponding variance for a range of annual exceedance probabilities. The output also includes estimates of the parameters of the log-Pearson Type III frequency distribution, including the logarithmic mean, standard deviation, skew, and mean square error of the skew. The output graph includes the fitted frequency curve, systematic peaks, low outliers, censored peaks, interval peaks, historic peaks, thresholds, and confidence limits.  PeakFQ is available as a web application or an R package that can be installed locally.

PeakFQ reads annual peaks from NWISWeb at https://nwis.waterdata.usgs.gov/usa/nwis/peak

 

Additional Resources

 

Screenshot showing the PeakFQ web interface.
User interface for PeakFQ web application.
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