Author(s): Monique Retallick; Mark Babister; Behzad Jamali; Harrison Babister; Nathan Dunning
Linked Author(s): Mark Babister, Monique Retallick, Behzad Jamali
Keywords: Climate change flood flood risk flood mapping
Abstract: A recent update was undertaken to the Climate Change Consideration chapter in the Australian design flood guidelines Australian Rainfall and Runoff 2019 Version 4.2 (Ball et al., 2019), to reflect the latest science. The outcomes of this guidance have major implications for the design flood estimation industry. While climate change guidance has been available in ARR since 2015, its implementation in practice and design requires a policy change. Climate change is used as a sensitivity test in flood studies resulting in hundreds of maps with no impact on the design or flood planning level. The new guidance is showing that climate change has already affected flood levels and there is an urgent need for policy on incorporating climate change into planning levels. While industry waits for policy to catch up with the science and to reduce the number of unnecessary model runs and calculations, the Climate Change Calculator has been developed. The calculator allows practitioners of varying levels of technical knowledge to easily understand how their climate risk will change over time, throughout the design life of a structure or with emissions pathway (SSP). The calculator has been expanded to allow users to upload design event flood level grids and interpolate design event grids factored by climate change. The interpolation facility will reduce the need for model runs and allow floodplain managers to easily determine the change in flood risk in their catchment. This paper documents the development of the tool and demonstrates its application using a case study in Brisbane, Queensland.
Year: 2025