Bushfire Hazard Assessment & Management Plan v4 - 7 Triller Court, Pomona

Bushfire Hazard Assessment & Management Plan v4                                 NCES REF: J000841
Lot 4 on SP320405 – 7 Triller Court, Pomona



To ensure emergency access and operational space for firefighters the subdivision layout
results in lots that are sited so that they are separated from the closest edge to the adjacent
medium, high or very high potential bushfire intensity area by a distance that achieves a
radiant heat flux level of 29 kilowatt per square metre or less.
To facilitate safe evacuation during a bushfire event, include a development footprint plan that
is located within 60 metres of the street frontage and sited to enable a route between the
development footprint plan and the street frontage with a gradient that does not exceed of
12.5 per cent.
Where reconfiguring a lot creating lots of 2000 square metres or less (i.e., Lots 4-8):
To ensure emergency access and operational space for firefighters the subdivision layout
results in lots that are sited so that they are separated from the closest edge to the adjacent
medium, high or very high potential bushfire intensity area by a distance that achieves a
radiant heat flux level of 29 kilowatt per square metre or less.
1. The building envelope, if identified at RaL stage, or
2. Where a building envelope is not identified, at all the lot boundaries.
Compliance with Assessment Benchmark 4 can be attained where building envelopes are
sufficiently separated from the nearby hazardous vegetation so that a radiant heat flux level
at any point on the building or envelope does not exceed 29 kW/m².
5.2.3    Radiant Heat Flux Setbacks
Determination of the setbacks required to satisfy Assessment Benchmark 4 can be identified
from the quantitative modelling output presented in Section 3.6 herein. The output results from
Plates 9-11 can be used to identify the setback requirements to achieve the <29 kW/m² radiant
heat flux SPP requirement. The required setbacks are shown in Table 2.
                Table 2 – Radiant Heat Flux Minimum Setbacks to secure <29kW/m²
                         VHC                      Direction    <29 kW/m² Setback*
                                                  and slope

                          9.1                     north - 7°         23.9m

                          9.1                     south - 9°         25.7m

                          9.1                     west - 1°          17.9m

* Source – Flamesol Minimum Distance calculator

Building envelopes have been nominated within each of the new allotments which are
provided with sufficient setback to the adjoining hazardous vegetation to comply with
Assessment Benchmark 4.
It is noted that Lot 7’s BLE is currently flanked by the low threat sub unit 4 (cleared
understorey) to the north however, given this area is also mapped as a Koala Habitat Area
(core) under the State mapping, the BLE has been positioned a minimum of 24m from the
edge of the unit, to account for potential understorey regrowth that may arise therein. As such
the APZ for Lot 7 does not rely on any vegetation clearing, including mowing of existing cleared
understorey conditions, within the mapped KHA.
Setbacks available within the allotments are to be prescribed as dedicated APZs and are to
be maintained in accordance with the landscape criteria specified in Section 5.6 for the life of
the development or until such time as an alternative setback can be justified (i.e. where
assessment methodologies change).
5.2.4    Recommended APZ’s
Lots 4-6
A minimum 24m wide APZ is recommended to be applied between the building envelopes



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