Earthquake Risk and Mitigation Assessment in the Yilgarn, WA

<div>We performed an earthquake risk assessment of seven smaller communities across the Yilgarn of Western Australia (WA): Northam, Merredin, Cunderdin, Kellerberrin, Wundowie, Meckering, and Tammin. This was done as a part of activities of a project entitled “Risk Assessment and Mitigation Study for Earthquakes in the Yilgarn” which, in addition to assessing risk posed to buildings by earthquakes, has a focus on understanding critical infrastructure system risk in the Yilgarn region. We modelled earthquake hazard based on the 2018 National Seismic Hazard Assessment and Geoscience Australia’s seismic site conditions map for Australia. Building exposure data was compiled by a desktop survey using available aerial imagery, purpose captured GoPro streetview type imagery and publicly available real estate information to record building attributes. We used Geoscience Australia’s current vulnerability functions which include a range of models collaboratively developed for high-risk unreinforced masonry buildings. The estimated average annualised loss ratios for the communities range from 0.008% to 0.027%, with the highest being for Kellerberrin, and the lowest being for Wundowie. We combined the damage related risk with the Australian Disaster Resilience Index to identify communities of high risk and lower resilience. Six earthquake scenario events were modelled along with the risk and impact reductions achieved through a virtual retrofit of old URM buildings in the communities. In this paper the outcomes of this research are presented and discussed in a national context.&nbsp;</div> Presented at the 2023 Australian Earthquake Engineering Society (AEES) National Conference