Dumaresq to Lismore Transmission Line Bushfire Risk Assessment

The project was undertaken to meet a Director General’s Requirement under Part 3A of the NSW Environmental Planning and Assessment Act 1979 (EP&A Act).

The assessmentaimed to strategically assess bushfire risk along the length of the proposed 205 km transmission line such that the line could be segmented according to risk. A suite of bushfire protection measures were recommended to mitigate the risk consistent with the risk ranking for each segment.

Bushfire risk was evaluated by investigating bushfire hazard and potential head fire intensity through analysis of a combination of fuel (vegetation), slope and aspect. A bushfire intensity model was created in a Geographic Information System (GIS) from these elements (according to mathematical formulae presented in scientific literature) in order to analyse the spatial patterns of bushfire risk and allow analysis of the consequence and likelihood of bushfire damage.

From this bushfire intensity model, we created a fire intensity map to provide a quantifiable risk measure and rank the bushfire risk to and from the proposed transmission line. The potential consequence of a bushfire impacting surrounding assets and the likelihood of this occurring was also analysed and evaluated using the bushfire intensity model.

A Risk Management Priority (RMP) map and table were developed with 68 individual risk areas, which allowed for the prioritisation of assets and allocation of risk treatments according to the assessed level of risk for each segment.

The method used by our team for this project is ideal for assessing the level of bushfire risk to and from many types of linear infrastructure and allows for consistent prioritisation across the infrastructure and recommendation of appropriate risk mitigation measures.