Models for 'what if?' scenarios

What if an earthquake hit central Adelaide? A major flood on the Yarra River through Melbourne? A bushfire on the slopes of Mount Wellington over Hobart?

‘What if?’ scenario modelling by the Bushfire and Natural Hazards CRC is helping government, planning authorities and emergency service agencies think through the costs and consequences of various options on preparing for major disasters on their infrastructure and natural environments and how these might change into the future.

The CRC research is based on the premise that to reduce both the risk and cost of natural disasters, we need an integrated approach that considers multiple hazards and a range of mitigation options.

The Decision support system project, led by Prof Holger Maier at the University of Adelaide, is completing a case study for Adelaide, and commenced further case studies for Melbourne and the whole of Tasmania.

Taking into account future changes in demographics, land use, economics and climate, the modelling will be able to analyse areas of risk both now and into the future, test risk reduction options, identify mitigation portfolios that provide the best outcomes for a given budget, and consider single or multiple types of risk reduction options, such as land use planning, structural measures and community education. CRC partners, along with local governments, have been engaged in the entire process, from direction on the hazards to include and feedback on process, to advice on how the modelling will be used when complete and by whom.

The modelling for Adelaide will be completed in 2017 and incorporates flooding, coastal inundation, earthquake, bushfire and heatwave, as well as land-use allocation. Expected impacts of these hazards have been modelled from 2015 to 2050 with an annual time step under different plausible future scenarios that were developed by end-users, showing the change in risks in different localities. Melbourne and Tasmania will follow next, incorporating bushfire, flood, coastal inundation and earthquake risk in Melbourne, and bushfire, coastal inundation and earthquake risk for Tasmania.

This is the only approach that compares different natural hazards and their mitigation options, while also taking into account long term planning. The ultimate aim is to develop a decision support framework and software system that is sufficiently flexible to be applied to large and small cities around Australia, helping planners from local councils through to state treasury departments answer the vital question on mitigation options that balance cost and impact: ‘what is the best we can be doing?’

This project is an outstanding example of the collaborative process that the CRC is all about, and incorporates findings from other CRC work on recognising non-financial benefits of management and policy for natural hazards, for example, the economic, social and environmental benefits of prescribed burning, the vulnerability of buildings to hazards, such as how they can be made more resilient through cost-effective retro-fitting for improved safety, and the benefits and understanding of community resilience efforts like improved warnings, community engagement, education, volunteering and community resilience.