Appendix C - Bushfire Hazard Assesment

3.0     LOCAL HAZARD MAP
3.1     GENERAL
The SPP reference documentation sets out the following methodology for preparing a Local Hazard Area
Map:
     Categorising the vegetation within the site in accordance with the vegetation hazard classes
        derived from QFES (2019)
     Using the patch and corridor filtering process to remove narrow corridors and small patches of
        hazardous vegetation
     Subdividing the identified vegetation hazard classes into bushfire hazard sub-units based on
        slope differences and vegetation hazard classes
     Assigning SPP Potential Bushfire Intensity classes to the sub-units
     Application of 100m Potential Impact Buffers to the amended sub-units to derive an overall Local
        Hazard Map.

3.2     PATCH AND CORRIDOR FILTERING
Section 4.2.6 of Bushfire Resilient Communities (QFES, 2019) outlines the patch and corridor filtering
process to modify potential intensity of small patches and corridors (based on Leonard et. al. 2017). The
process involves the following three stages:
      Merging small patches of a single Vegetation Hazard Class less than 0.5ha
      Merging small Vegetation Hazard Class patches between 0.5 and 1ha with higher or moderate
         fuel loads (greater than 8 tonnes/ha)
      Removing narrow corridors of vegetation less than 50m wide through a process of patch erosion
         and dilation. These small patches are merged with surrounding vegetation by allocating a patch
         to the Vegetation Hazard Class that is most common to the patch boundary.

3.3     CALCULATION OF POTENTIAL BUSHFIRE INTENSITY
The Potential Bushfire Intensity of each identified sub-unit has been calculated by inputting the site-
specific input parameters discussed in Section 2.1 into the FLAMESOL computer model. FLAMESOL uses
industry standard bushfire equations and allows numerous input variables to be adjusted including fuel
loads, fire danger index, site slope and distance to vegetation. Table 1 details the Potential Bushfire
Intensity classes and their corresponding potential fire-line intensity (KW/m) values as prescribed within
Leonard et. al. 2017.
Table 1 – Potential Bushfire Intensity Classes

 POTENTIAL BUSHFIRE INTENSITY                         POTENTIAL FIRELINE INTENSITY

 Very High                                            >40,000 kW/m

 High                                                 20,000-39,999 kW/m

 Medium                                               4,000 – 19,999 kW/m

Figures 1-3 are presented below and have been prepared as per the above referenced methodology.

October 2021                          BUSHFIRE HAZARD ASSESSMENT                                  Page: 10
                                      797 Ringtail Creek Road, Pomona