Forest Fire Management Victoria uses best available models and data each year to calculate the metrics presented in the fuel management report. As our technology improves, better data becomes available, mapping accuracy improves or we change our method of calculation of metrics to better represent what happened during the year, some metrics, such as modelled bushfire risk or reported costs, can change. A summary of these changes can be seen in the tables below. We continually work to improve the data and science behind our decisions and fully expect updates to be made regularly in light of these improvements. Comparisons between this report and past and future reports should be made in that light, and it is recommended that for the most accurate view of current and historic figures, you always consult the most recent fuel management report.
Changes to reported bushfire risk
In late 2016, we updated the inputs into the Phoenix RapidFire bushfire simulation software and the residual risk calculation process by:
- improving fuel-type mapping by more accurately mapping the extent of woody vegetation across Victoria; by updating plantation, irrigation area and water-body mapping; and by expanding fuel-type mapping into South Australia and New South Wales
- deploying a new version of the Phoenix RapidFire software — version 4007 — which improves bushfire spread simulations by better accounting for convection, spotting and ember density
- expanding the Phoenix ignition grid by 40 km into South Australia and New South Wales to complement the expansion of the fuel-type mapping
- improving the accuracy of address point locations, which are used to estimate residual risk, across Victoria. These improvements resulted in updated residual risk profiles, which show risk to be about 10% less than estimated using the previous version of the Phoenix software and previous data.
The 2016 updates to the Phoenix RapidFire model were applied to all previously reported bushfire risk figures which resulted in a decrease in bushfire risk reported in fuel management reports dating back to 2012-13.
In 2019, we improved the mapping and accounting of areas treated by planned burning to improve the accuracy of our fire history data. The improvements to the fire history dataset were applied to all previously reported risk figures which resulted in an increase to reported bushfire risk in 2016–17 and 2017–18. These changes can be seen in Table 13 below.
Table 13. Changes and improvements to the reported bushfire risk figure and reasons for the change
Report year | 2012-13 | 2013-14 | 2014-15 | 2015-16 | 2016-17 | 2017-18 | 2018-19 |
|---|---|---|---|---|---|---|---|
Reported risk in that year | 60% | 62% | 65% | 70% | 63% | 66% | 69% |
Reported risk in current year | 53% | 57% | 57% | 62% | 67% | 68% | 69% |
Reason for change | 2016 Phoenix model update | 2016 Phoenix model update | 2016 Phoenix model update | 2016 Phoenix model update | Updates to Phoenix software and data inputs 2019 improvements to fire history layer | 2019 improvements to fire history layer | No change - current risk |
Changes to reported costs
Changes in the split between direct and indirect costs have been applied retrospectively in Table 14 below to enable a direct comparison between financial years the four financial years shown, based on the accounting methodology applied in 2018-19.
The fuel management program expenditure is split between direct and indirect costs. Specific amendments have been made to better capture the activities related to fuel management and non-fuel management expenditure due to continual improvements made to the accounting methodology and categorisation of expense types over time. The changes reported herein for direct and indirect expenditure within the fuel management program for 2015-16, 2016-17 and 2017-18 are the result of changes made to the categorisation of costs as being direct, indirect and/or non-fuel management expenses.
Direct costs relate to expenditure that can be directly and reliably assigned to individual operations such as materials, plant and aircraft hire, overtime and allowances, accommodation and meals. Indirect fuel management costs include expenses relating to base salaries, training, vehicles, equipment, planning and community engagement. Non-fuel management expenses are typically those relating to preparedness and fire and emergency response activities, such as fire radio network costs, systems and aviation spend.
Table 14. Changes to reported fuel management expenditure in the current and previous fuel management reports
Report year | 2015-16 ($m) | 2016-17 ($m) | 2017-18 ($m) | 2018-19 ($m) |
|---|---|---|---|---|
Total Fuel Management expenditure reported in current year (based on 2018-19 accounting method) | 108.5 | 97.9 | 113.5 | 121.7 |
Direct Fuel Management expenditure reported in current year | 12.3 | 11.2 | 14.6 | 18.2 |
Indirect Fuel Management expenditure reported in current year | 96.2 | 86.7 | 98.9 | 103.5 |
Total Fuel Management expenditure reported that year | 133.2 | 107.9 | 107.8 | 121.7 |
Direct Fuel Management expenditure reported that year | 44.3 | 40.0 | 30.4 | 18.2 |
Indirect Fuel Management expenditure that year | 88.9 | 67.9 | 77.4 | 103.5 |
Net change in Fuel Management reported expenditure | -24.7 | -10.0 | 5.7 | No change |
Page last updated: 23/12/20