The latest edition of the Australian Rainfall and Runoff guidelines has been released and is expected to help engineers, architects and policy makers better predict the impact of flooding in Australia. The updated flood modelling guidelines will also help build resilient cities in the face of climate change.

Mark Babister, Chair of the ARR Technical Committee and past Chair of Engineers Australia’s National Committee on Water Engineering, said the 2016 Australian Rainfall and Runoff guidelines (ARR 2016) represent a significant improvement in best practice for flood modelling. Developed on the basis of rainfall and stream flow data, case studies and computer modelling, ARR 2016 will be used by engineers, designers, flood practitioners and policy makers to understand how much rainfall to expect and where to expect the water to go once it hits the ground.

According to Babister, estimation methods have improved significantly since the last edition of the ARR in 1987 with more complex models developed to enable engineers to provide a more robust estimate of flood risk.

Now in its fourth edition, ARR 2016 is the first to be entirely based on Australian data, analysing 100,000 storm events and an additional thirty years of data to better reflect Australia’s variable landscape. Though extreme flooding events in major centres in recent years are mostly remembered, Babister says ARR 2016 is equally important to understanding the effects of dryer weather events such as El NiƱo, particularly as climate change induced extreme weather becomes more common.

He explained that ARR 2016 represents the first inclusion of climate change guidelines, drawing on the most recent climate science from CSIRO, the Bureau of Meteorology and the IPCC Fifth Assessment. Babister added that ARR has been a crucial tool for engineers and planners for many years, and the latest improved edition of the ARR 2016 is expected to lead to better flood mitigation solutions and ultimately, a more predictable environment for engineers to build safer structures.

Published by Engineers Australia with funding from the Australian Government, the 2016 Australian Rainfall and Runoff guidelines can be accessed at