What the PMF?

This page provides supplemental resources to accompany the 8 Sep 2021 free AWS webinar “What the PMF“, addressing the Probable Maximum Flood. This webinar supports a training course dedicated to the estimation of extreme events in Australia: ARR Course #6: Extreme Events. View the recording here:


Previous Webinars

  • Hear an overview of Course 6:

  • Learn about climate change impacts on extreme event hydrology, including the PMF:

  • Daryl Lam discusses palaeoflood hydrology:

  • Learn about GLOFs and other events that can exceed PMF estimates by orders of magnitude:


Extreme Events in Australia

[Citation: Nathan, R. and Weinmann, P.E. (2019): Book 8 – Estimation of Very Rare to Extreme Floods in Ball J, Babister M, Nathan R, Weeks W, Weinmann E, Retallick M, Testoni I, (Editors), Australian Rainfall and Runoff: A Guide to Flood Estimation. Commonwealth of Australia (Geosciences Australia). ISBN 978-1-925297-07-2.]


Rory Nathan Publications:

  • Nathan, R.J., Weinmann, P.E., and Gato, S (1994): A quick method for estimation of the probable maximum flood in south-east Australia. International Hydrology and Water Resources Symposium: Water Down Under, November, Adelaide, I.E. Aust. Natl. Conf. Publ. No. /94, 229-234.  See also Nathan, R.J., Weinmann, P.E., and Minty, L. (1999): Estimation of the Annual Exceedance Probability of Probable Maximum Precipitation in South East Australia, Aus J Water Resources 3(1), 143-154. 


Daryl Lam Publications:


Krey Price Publications:

  • This 2020 International Mine Water Association paper discusses the merits and challenges associated with designing infrastructure for PMF events:

  • This 2018 HWRS paper addresses event-based versus duration-based assessments for extreme design events:

  • This April 2019 Engineers Australia seminar discusses the question of event-based versus duration-based assessments for extreme events…with a wide range of possible answers:


USGS Publications:

World’s Largest Floods, Past and Present: Their Causes and Magnitudes, USGS 2004: Quantitative Paleoflood Hydrology, USGS 2021:

USGS, 2008: An Evaluation of Selected Extraordinary Floods in the U.S. 
Appendix A: Individual Evaluations of 30 Peak Discharges from Extraordinary Floods


Additional publications referenced in the presentations


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