About the Technique

This Regional Flood Frequency Estimation (RFFE) technique has been developed by Dr Ataur Rahman and Dr Khaled Haddad from the University of Western Sydney with the assistance of Professor George Kuczera from the University of Newcastle and Mr Erwin Weinmann. Many other people have contributed to this project as outlined in the acknowledgments.

The technique is based on data from 853 gauged catchments. For application, Australia is divided into six data-rich regions, two data- poor/arid regions and six fringe zones. A region-of-influence (ROI) approach was used to form sub-regions within the data-rich regions. In these sub-regions a Bayesian generalised least squares regression was adopted to regionalise the three parameters of the LP3 distribution. In the data-poor/arid regions an index method was applied, using the 10% AEP flood quantile as the index variable. An interpolation procedure is used to derive flood estimates for sites located in fringe zones.

A description of the RFFE technique is available in Book 3 of Australian Rainfall and Runoff. Full details of the technique are available in the ARR project reports.