Extreme flooding could return in South-East Queensland

16 Jan 2017
2011 floods, Queensland - State Library of Queensland image

History has a devastating tendency to repeat itself when it comes to extreme flooding in South-East Queensland, researchers behind a new study have warned.

The University of Queensland-led research project investigating the recurrence of extreme floods in South-East Queensland, has been released six years after the devastating Lockyer Creek floods.

Associate Professor Jacky Croke of UQ’s School of Earth and Environmental Sciences said there was no place for complacency.

“History has an uncomfortable way of repeating itself,” she said.

“The goal of our research was to contribute to the understanding, prediction and management of extreme flood events in the Lockyer Valley and broader South-East Queensland region.

“We discovered major floods occurred on the Lockyer Creek in 500AD, 1300 and in the 1700s – well before historical and gauging station information was available – and in the 1890s and 1970s.

“While the hydrological characteristics of the Lockyer Creek 2011 flood have been evaluated through coronial inquests, there are concerns about when the next ‘big event’ could occur and how other populated areas could be affected.”

Associate Professor Croke said the history of river discharge records was too short to determine the likely recurrence intervals of extreme floods, but the study had reduced uncertainty in flood prediction by about 50 per cent. 

“Government, industry and university colleagues worked on the Australian Research Council Linkage-funded project which reconstructed a time series of major floods for Lockyer Creek going back 2000 years.

“The study predicted river channel and floodplain susceptibility to floods in the Lockyer Valley and located areas of high risk. 

“Consistently defining floodplain types, spill out zones and locations of high stream power, and aligning management actions with the right erosion process would take SEQ a long way to better flood hazard management and downstream water quality protection.” 

Associate Professor Croke said findings from the project made a significant contribution to the future management of floods in the region.

“We identified actions can be undertaken to meet the future objectives of improved flood hazard mapping and ‘keeping soil on the paddock’ through appropriate catchment action plans,” she said.

The research (http://www.thebigflood.com.au) will be incorporated into climate change predictions, water quality protection and river management in Australia.

The project involved researchers from Macquarie University, the University of Lincoln in the United Kingdom, the University of Wollongong, Griffith University, the Queensland Department of Science, Information Technology and Innovation, and Seqwater.

Partner organisations included the Queensland Government, Seqwater and the Lockyer Valley Regional Council.

Media: Associate Professor Jacky Croke, jacky.croke@uq.edu.au, 07 3365 6033 or 0419 171 964.