Clear skies for new Australian Rainfall and Runoff update

23 May 2019

Local flood modellers now have access to more reliable and robust data than ever before following the release of the latest update to Australian Rainfall and Runoff.

Chief of Positioning and Community Safety, Dr Andy Barnicoat said his team at Geoscience Australia had worked closely with Engineers Australia to address feedback from users following the completion of a comprehensive update to the national guideline document, data and software suite in 2016.

“In 2016, we released the most comprehensive update to Australian Rainfall and Runoff in three decades. Working with Engineers Australia, we added an additional 30 years of data collected from across Australia, including observations from more than 10,000 rainfall gauges and 100,000 storm events,” Dr Barnicoat said.

“Since 2016, we’ve been gathering feedback from the users of Australian Rainfall and Runoff. The improvements we’ve made in the 2019 update reflect their requirements.

“An up-to-date Australian Rainfall and Runoff is essential for reliable and robust estimates of flood risk, which in turn, help to ensure the safety and sustainability of Australian infrastructure, communities and the environment.

“For example, making sure new developments are located in safer areas and new infrastructure, such as roads and bridges, are designed appropriately.”

Registrar Engineers Australia Glen Crawley said the updates made in 2019 reflect a commitment to keep building a quality, up-to-date product for assessing flood risk.

“Many of the previously draft chapters are now finalised, providing flood modellers with greater confidence that the guidelines represent best practice, using national scale data and information,” Mr Crawley said.

“The methods for modelling floods in complex urban environments have been finalised. These methods now allow the modeller to retain stormwater within urban landscapes, manage stormwater quality, maximise the potential of the stormwater resource and to slow flows into receiving waterways.

“The methodology for calculating design rainfalls and river-flows for future scenarios has been updated. The methodology for extreme rainfalls now reflects differences required for use in dam studies, and floodplain management. As an input to hydrodynamic models, this update will help modellers to more accurately predict where flood will occur and the potential impact.”

Dr Barnicoat said Australian Rainfall and Runoff was an example of how the public and private sectors can work together to help make our communities more flood safe.

“The Queensland floods from earlier this year, which inundated Townsville homes and killed masses of cattle in the state’s north-west, were a timely reminder of just how destructive these type of events can be,” Dr Barnicoat said.

“Australian Rainfall and Runoff 2019 provides quality guidance for policy decisions and projects involving essential infrastructure such as transport and water. It also contributes to more effective town planning and better delivery of flood warnings.”

Dr Barnicoat said he hoped to see Australian Rainfall and Runoff used more widely in the future.

“We know that a lot of flood modellers are already using the new Australian Rainfall and Runoff but we think it also has the potential to be a useful tool for professional engineers and planners, particularly those within local government,” Dr Barnicoat said.

Web and PDF versions of Australian Rainfall and Runoff 2019 are freely available from arr.ga.gov.au. For future updates, subscribe to Australian Rainfall and Runoff news.