Counting bushfire-prone addresses in the Greater Sydney region

Greater Sydney is one of the more bushfire-prone areas in Australia, a fact exacerbated by the region being home to a quarter of Australia’s population and a concentration of high-value real estate and industrial and commercial assets. Long-term projections of climate change suggest that the region is likely to experience more fire-weather days. Altogether, bushfires pose a significant risk for the region. Risk Frontiers’ FireAUS project aims to quantify bushfire risk for all addresses in Australia. This paper introduces the main methodology that comprises two components: (1) revealing evidence of spatial patterns of fire penetration into urban areas using data from major historical fires; and (2) quantifying site-specific environmental attributes that may predispose properties to bushfire risk. For the Greater Sydney region, a total of 2.87 million addresses have been analysed, and some 6.6% (about 190,000) of all addresses may be at a relatively greater risk owing to their close proximity within about 80 m to areas of extensive bushland. Results are further detailed at two different spatial units: Local Government Areas and CRESTA (Catastrophe Risk Evaluation and Standardizing Target Accumulations) zones as used by the insurance industry. The results will be useful for local councils, the insurance industry and emergency management, and help risk managers prioritise resources and make more realistic bushfire prevention planning.