Extreme Flood Events in Southeast Queensland - Evidence and Implications
The loss of lives and damages to infrastructure and economy as a result of the 2011 and 2013 flood events in Queensland highlight the need to better understand extreme flood events. The relatively short period of systematic gauging records limits the effectiveness of predicting and mitigating such events. Coupled with historical records, the use of Slackwater Deposit (SWDs) as a mean of paleoflood hydrology has the potential to extend these extreme flood records beyond the systematic records from the gauges.
Deposition of fluvially-transported sediments during extreme flood events can be located in a variety of geomorphic settings and dated to extend and improve existing systematic (gauging station) data. Such an analogue of extreme floods can go beyond improving flood modelling, prediction and mitigation. Links have been made between paleoflood hydrology/ fluvial sedimentary records and global climate change (e.g. Knox, 2000, Redmond et al. 2002, Macklin et al. 2012). At a local and/or regional scale, temporal variability of flood magnitude and frequency can be directly influenced by regional climatic drivers. A longer record of extreme flood events can provide a better understanding of the role of climatic driver(s) in shaping these extreme events.