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Appendix D - Bushfire Hazard Assessment and Management Plan
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Log in to see the plans as drawnBUSHFIRE HAZARD ASSESSMENT
& MANAGEMENT PLAN
RURAL-RESIDENTIAL SUBDIVISION
21 JIRRIMA CRESCENT, COOROIBAH
LOT 46 ON RP136461
52A Park Rd Nambour QLD 4560 / Ph: 0428 221 983 / Email: [email protected]
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TABLE OF CONTENTS
1.0 INTRODUCTION......................................................................................1
1.1 PURPOSE......................................................................................................................................1
1.2 ASSESSMENT AREA .......................................................................................................................1
1.3 NOOSA COUNCIL BUSHFIRE OVERLAY..............................................................................................3
1.4 STATE PLANNING POLICY BUSHFIRE PRONE AREA OVERLAY ..............................................................3
1.5 SURROUNDING LANDSCAPE ...........................................................................................................4
1.6 TOPOGRAPHY ...............................................................................................................................6
1.7 VEGETATION ................................................................................................................................7
2.0 BUSHFIRE HAZARD ASSESSMENT ............................................................9
2.1 STATE ASSESSMENT METHODOLOGY ..............................................................................................9
2.1.1 General .........................................................................................................................9
2.1.2 Vegetation Hazard Classes .........................................................................................9
2.1.3 Maximum Landscape Slope ........................................................................................9
2.1.4 Fire Danger Index ...................................................................................................... 10
3.0 LOCAL HAZARD MAP ............................................................................11
3.1 GENERAL .................................................................................................................................... 11
3.2 PATCH AND CORRIDOR FILTERING ................................................................................................ 11
3.3 CALCULATION OF POTENTIAL BUSHFIRE INTENSITY ........................................................................ 11
5.0 BUSHFIRE RISK ASSESSMENT ................................................................16
5.1 GENERAL .................................................................................................................................... 16
5.2 RISK FROM IDENTIFIED HAZARDOUS VEGETATION ......................................................................... 17
6.0 BUSHFIRE IMPACT REDUCTION ...................................................18
6.1 GENERAL .................................................................................................................................... 18
6.2 SETBACKS................................................................................................................................... 18
6.2.1 Asset Protection Zone Design .................................................................................. 18
6.3 FIREBREAKS ................................................................................................................................ 19
6.4 WATER SUPPLY ........................................................................................................................... 20
6.5 VEHICULAR ACCESS ..................................................................................................................... 21
7.0 NOOSA PLAN 2020 – BUSHFIRE HAZARD OVERLAY CODE .....22
8.0 CONCLUSION ...................................................................................29
9.0 REFERENCES ...................................................................................30
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Disclaimer
This assessment has been prepared by Equilibrium Ecology Pty Ltd for the specified Client and may only be used and relied
upon for the purposes set out in this report. No responsibility is held to any person other than the Client for any decision or
action arising from or in connection with this report. All opinions and conclusions are based on assumptions detailed in this
report and no responsibility is held for any error or omission arising from these assumptions being incorrect.
This assessment has been based on site conditions present at the time of preparation and are relevant to the nature of the
development proposed. The assessment relies on current bushfire hazard assessment methodologies as described in this
report. These methodologies may not consider catastrophic bushfire events which may occur from time to time. By their
nature, bushfires are unpredictable, and no guarantee can be provided or should be assumed that the area will not be affected
by bushfire at some time. Landowners/occupants should be aware of the unpredictable nature of bushfire and potential
consequences of such events and should be responsible for their property by being prepared for extreme events accordingly.
To the extent permitted by law, Equilibrium Ecology Pty Ltd excludes all liability to any person for any consequences, including
but not limited to all losses, damages, costs, expenses, and any other compensation, arising directly or indirectly, from using
this report (in part or whole) and any information or material contained in it.
Document Issue
Version Number Date Authorised for Issue
1 3 December 2021 N. Willis (B. Sc., Dip. CLM., mAABR,
mEIANZ) – Director/Principal Ecologist
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1.0 INTRODUCTION
1.1 PURPOSE
This Bushfire Hazard Assessment and Management Plan has been prepared to assess the degree of
bushfire hazard and associated risk acting on Lot 46 on RP136461 located at 21 Jirrima Crescent,
Cooroibah (herein referred to as ‘the site’). The applicant is seeking a reconfiguration of a lot development
permit from Noosa Council for a rural residential subdivision (1 Lot into 2 Lots). The proposed Plan of
Development has been provided as Appendix A. This assessment has been undertaken to determine the
specific extent of bushfire hazard acting on the proposed development and the bushfire mitigation
measures required to safely undertake the development. This report has been prepared as per the
requirements for undertaking a Bushfire Hazard Assessment and preparing a Bushfire Management Plan
as detailed in Bushfire Resilient Communities. Technical Reference Guide for the State Planning Policy State
Interest ‘Natural Hazards, Risk and Resilience - Bushfire’ (Queensland Fire and Emergency Services, 2019).
1.2 ASSESSMENT AREA
QFES (2019) defines the assessment area as the development footprint and all land within 150m of the
extent of the development footprint. In this instance, the entire site is proposed for development,
therefore the assessment has been undertaken for the entire site and a 150m assessment buffer
surrounding the site.
The site is approximately 4.39ha and currently contains an existing dwelling and associated outbuildings
in the eastern extent. The site is predominantly cleared of vegetation, with a low density of trees retained
adjacent to a central waterway and scattered individual trees over mown grass in the west of the site.
Predominantly cleared residential allotments are located to the east and immediate south of the site, with
a semi-vegetated allotment located to the north. Remnant native vegetation is located within a Noosa
Council managed park immediately to the west of the site. Plate 1 depicts the existing site conditions
within the assessment area.
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Plate 1: Assessment Area (Source: QLD Globe)
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1.3 NOOSA COUNCIL BUSHFIRE OVERLAY
The western extent of the site is located within a mapped High Potential Bushfire Intensity area under the
Noosa Plan 2020 Bushfire Overlay. An additional narrow band of High Potential Bushfire Intensity extends
over the narrow band of riparian vegetation within the centre of the site. The majority of the remainder
of the site (precluding the far eastern extent) is located within a Potential Impact Buffer which extends
100m from the mapped High Potential Bushfire Intensity area (refer to Plate 2).
Plate 2: Noosa Plan 2020 Bushfire Hazard Overlay (Source: Noosa Interactive Mapping)
1.4 STATE PLANNING POLICY BUSHFIRE PRONE AREA OVERLAY
The western extent of the site is located within a mapped High Potential Bushfire Intensity area under the
State Planning Policy Bushfire Prone Area Overlay. An additional narrow band of High Potential Bushfire
Intensity extends over the narrow band of riparian vegetation within the centre of the site. The majority
of the remainder of the site (precluding the far eastern extent) is located within a Potential Impact Buffer
which extends 100m from the mapped High Potential Bushfire Intensity area (refer to Plate 3).
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Plate 3: State Planning Policy Bushfire Hazard Mapping (Source: SPP Mapping)
1.5 SURROUNDING LANDSCAPE
The site is located within a semi vegetated rural-residential landscape. The dominant unit of hazardous
vegetation in proximity to the site is an area of native vegetation of approximately 150m width contained
within Council managed parkland to the west of the site. Additional semi-vegetated private freehold
allotments form a mosaic of vegetation which is interspersed with cleared areas. The landscape
surrounding the site is depicted in Plate 4.
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Plate 4: Surrounding Landscape (Source: Queensland Globe)
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1.6 TOPOGRAPHY
The site is located on low-lying land adjacent to the Noosa River floodplain. Site topography is
predominantly flat, with subtle variation in elevation. A minor drainage line traverses the centre of the
site, with a third order tributary to Ringtail Creek located within the Council parkland to the west of the
site. The site reaches a topographic high of approximately 9m AHD in the eastern extent and descends to
a topographic low of 4m AHD flanking the central drainage line and a low of 3m AHD along the western
boundary. Plate 5 & 6 depict topography conditions surrounding the site.
Plate 5: Topography/Hill shade (Source: QLD Globe)
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Plate 6: Topography (Source: Noosa Council Interactive Mapping)
1.7 VEGETATION
A site assessment was undertaken on 16 November 2021. Vegetation within the 150m assessment area
to the west of the proposed development site is dominated by Melaleuca open forest. The canopy has
attained a height of approximately 20m, with crown cover of approximately 60-70%. The canopy is
dominated by Melaleuca quinquenervia (broad-leaved tea tree), with Eucalyptus robusta (swamp
mahogany) and Lophostemon suaveolens (swamp box). The mid-storey is sparse and contains
regenerating canopy species. The understorey is dense and is dominated by a diversity of sedges and ferns
including dense areas of Telmatoblechnum indicum (bungwahl fern). The vegetation community is
mapped by the Queensland Herbarium as containing Regional Ecosystem RE 12.3.4 which is described as
Melaleuca quinquenervia, Eucalyptus robusta woodland on coastal alluvium. The vegetation community
is analogous with Vegetation Hazard Class 22.1 (VHC 22.1) Melaleuca open forests on seasonally
inundated lowland coastal swamps (QFES, 2019). Plate 7 depicts typical conditions within the Melaleuca
swamp to the west of the site.
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Plate 7: Melaleuca open forest
The only other vegetation type present within the 150m assessment area consists of low grazed pasture
and established lawns and gardens with low density mature trees within the rural-residential allotments
surrounding the site. The vegetation type within the rural-residential allotments is analogous with VHC
39.2 – Low to moderate tree cover in built up areas (QFES, 2019).
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2.0 BUSHFIRE HAZARD ASSESSMENT
2.1 STATE ASSESSMENT METHODOLOGY
2.1.1 General
The State Planning Policy requires a site-specific bushfire hazard assessment to be undertaken when a
development site is located within a mapped Bushfire Hazard Area. Chapter 2, Part 1, Section 8, Item 4(a)
of the Planning Act 2016 states that where there is an inconsistency between a State Planning Policy and
a local government planning instrument, a State Planning policy applies instead of a local planning
instrument. The SPP mapping is therefore used as the trigger for assessment against Council’s Bushfire
Overlay. Furthermore, the site-specific hazard mapping required by the Planning Scheme is to be prepared
consistent with the methodology adopted to prepare the SPP mapping.
The methodology used to prepare the SPP mapping is described in the following publications:
Natural Hazards, Risk and Resilience –– Bushfire State Planning Policy – state interest guidance
material (The Department of Infrastructure, Local Government and Planning, 2019)
Bushfire Resilient Communities. Technical Reference Guide for the State Planning Policy State
Interest ‘Natural Hazards, Risk and Resilience - Bushfire’ (Queensland Fire and Emergency Services,
2019)
The preparation of a Local Hazard Area Map has been undertaken for the site in accordance with the
methodology described in the above referenced documents. The input parameters used to determine the
bushfire hazard acting on the site are detailed in the sections below.
2.1.2 Vegetation Hazard Classes
Fuel loads need to be determined when preparing a bushfire hazard assessment. The Queensland Fire
and Emergency Services (QFES) refers to the process for identifying, classifying and mapping vegetation
hazard classes as a Vegetation Hazard Class Assessment. In accordance with the methodology outlined in
Section 6 of the Bushfire Resilient Communities (QFES, 2019), the following Vegetation Hazard Classes
(VHC) were identified within the assessment area (which includes a 150m buffer surrounding the site):
VHC 22.1 – Melaleuca open forests on seasonally inundated lowland coastal swamps – which is
attributed a combined surface/near-surface fuel of 23.4t/ha and a total potential fuel load of
28.4t/ha
VHC 39.2 – Low to moderate tree cover in built up areas – which is attributed a combined
surface/near-surface fuel of 5t/ha and a total potential fuel load of 8t/ha
2.1.3 Maximum Landscape Slope
The slope of the land is a major determinant of fire behaviour. Fire burns faster as it travels up a slope,
via the preheating of unburnt fuels ahead of the fire, increasing the rate of spread and fireline intensity.
Conversely, fires move more slowly as they travel downslope. Fireline intensity (kW/m) is a function of
the rate of spread. As a general rule, the rate of fire spread (and fireline intensity) doubles up a 10-degree
slope and quadruples up a 20-degree slope (QFES, 2019).
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The hazardous vegetation influencing the proposed development is located across slope of the
development area. Where the slope under hazardous vegetation is located across slope, it is considered
‘upslope’ irrespective of the slope of land between the site and the edge of the hazardous vegetation.
Note that for the purposes of undertaking a bushfire hazard assessment, where the topography is flat or
where vegetation is located upslope of an assessment site, a slope of 1 degree is required to be used to
satisfy the mathematical formula, however it has negligible impact on the calculations.
2.1.4 Fire Danger Index
The Queensland Government produce a publicly available data package which includes selected inputs
and information used by the CSIRO in conjunction with the QFES to prepare the State-wide Bushfire
Hazard Area (Bushfire Prone Area) mapping (July 2014). The data includes Fire Weather Severity (Fire
Danger Index - FDI). A review of the dataset for the assessment area indicates that the site is located
within a band of FDI 47.
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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) (refer to Figure 1)
Using the patch and corridor filtering process to remove narrow corridors and small patches of
hazardous vegetation (refer to Figure 1)
Subdividing the identified vegetation hazard classes into bushfire hazard sub-units based on
slope differences and vegetation hazard classes (refer to Figure 2)
Assigning SPP Potential Bushfire Intensity classes to the sub-units (refer to Figure 2)
Application of 100m Potential Impact Buffers to the amended sub-units to derive an overall Local
Hazard Map (refer to Figure 3)
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:
Remove small, isolated patches of a single Vegetation Hazard Class less than 1ha if they are
further than 100m from any other continuous fuel greater than 2 hectares in size
Downgrade the intensity of small patches (0.5 to 3 ha). This process downgrades the effective
fuel load of continuous vegetation patches 0.5 to 2ha by 66%, and 2 to 3ha by 50% if they are
completely surrounded by either no fuel or by discontinuous fuel further than 100m from any
other continuous-fuel vegetation patch greater than 2 hectares in size
Removing narrow corridors of vegetation less than 50m wide and less than 0.5ha 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
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. The Flamesol modelling used to determine the SPP Potential Bushfire Intensity classes has been
included as Appendix B.
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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.
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BUSHFIRE HAZARD ASSESSMENT 21 JIRRIMA CRESCENT, COOROIBAH FIGURE 1 VEGETATION HAZARD CLASSES LEGEND |__| 21,JIRRIMA CRESCENT, COOROIBAH : 3 150m ASSESSMENT BUFFER a CL] VHC 22.1 - MELALEUCA OPEN FOREST [___] vic 39.2- Low To MODERATE TREE COVER
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BUSHFIRE HAZARD ASSESSMENT 21 JIRRIMA CRESCENT, COOROIBAH FIGURE 2 HAZARD SUB-UNITS LEGEND | 25 HATCHMAN COURT, ELIMBAH — HE 3 150m ASSESSMENT BUFFER A LC] LOW POTENTIAL BUSHFIRE INTENSITY q % SS CL] MEDIUM POTENTIAL BUSHFIRE INTENSITY Maximum Potential Potential Maximum Potential Potential Landscape Fireline Fireline Landscape Fireline Fireline Slope Intensity Intensity Slope Intensity Intensity
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BUSHFIRE HAZARD ASSESSMENT 21 JIRRIMA CRESCENT, COOROIBAH FIGURE 3 LOCAL HAZARD MAP LEGEND | 21 JIRRIMA CRESCENT, COOROIBAH 50m ASSESSMENT BUFFER / Dy LOW POTENTIAL BUSHFIRE INTENSITY [ HIGH POTENTIAL BUSHFIRE INTENSITY | POTENTIAL IMPACT BUFFER
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5.0 BUSHFIRE RISK ASSESSMENT
5.1 GENERAL
A bushfire risk assessment for the proposed development has been prepared generally in accordance with
the SPP Bushfire (2019) and AS/NZS ISO 31000:2018 – Risk Management Methodology.
The bushfire risk assessment details the likelihood that the proposed new dwelling adjoining the
hazardous vegetation will be exposed to radiant heat impact from the adjacent confirmed Potential
Bushfire Intensity areas depicted on Figure 3.
According to AS/NZS ISO 31000:2018, a ‘hazard’ is defined as a source of potential harm or a situation
with a potential to cause loss, whereas a ‘risk’ is the chance of something happening that will have an
impact on objectives measured in terms of consequences and likelihood. The SPP Bushfire (2019) refers
to ‘acceptable risk’, ‘tolerable risk’, and ‘intolerable risk’ which are defined below.
Acceptable risk
A risk that, following an understanding of the likelihood and consequences, is sufficiently low to require
no new treatments or actions to reduce risk further. Individuals and society can live with this risk without
feeling the necessity to reduce the risks any further.
Tolerable risk
A risk that, following an understanding of the likelihood and consequences, is low enough to allow the
exposure to continue, and at the same time high enough to require new treatments or actions to reduce
risk. Society can live with this risk but believe that as much as is reasonably practical should be done to
reduce the risks further.
Intolerable risk
A risk that, following an understanding of the likelihood and consequences, is so high that it requires
actions to avoid or reduce the risk. Individuals and society will not accept this risk and measures are to be
put in place to reduce risks to at least a tolerable level.
AS/NZS ISO 31000:2018 defines ‘Likelihood’ as the chance that something might happen. Likelihood can
be defined, determined, or measured objectively or subjectively and can be expressed either qualitatively
or quantitatively (using mathematics). The following ‘likelihood’ categories for the probability of the
assessed bushfire attack mechanisms impacting the assessment area have been adopted within this
assessment:
Likely - Will probably occur
Unlikely - Could occur but doubtful
The determination of whether a bushfire event is likely or unlikely to impact the site has been based on
the relative position of hazardous vegetation to the site. Typical seasonal fire winds within south-east
Queensland originate from the north to north-west to south-west. Where hazardous vegetation is located
upwind of the site under dominant seasonal fire winds, the site is considered to be exposed to a likely
probability of impact. Where hazardous vegetation is located downwind of the site under typical seasonal
fire winds, the site is considered to be exposed to an unlikely probability of impact.
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5.2 RISK FROM IDENTIFIED HAZARDOUS VEGETATION
The Plan of Development depicts the proposed new building envelope within Lot 2 within 60m of the
identified hazardous vegetation to the west of the site. The likelihood of a fire approaching from the north
to west is considered likely, given dominant regional fire weather winds are derived from the north-west
to south-west.
The separation distance offered to the adjoining vegetation is the primary driver of the assigned level of
risk and is determined with consideration to the Flamesol modelling output undertaken in Section 3.3 and
presented as Appendix B. A minimum of 60m separation has been provided between the proposed Lot 2
building envelope and the VHC 22.1 hazardous vegetation to the west. The 60m separation will provide a
new dwelling within Lot 2 a setback distance sufficient to achieve less than 10kW/m2 radiant heat impact
and will result in an acceptable level of bushfire risk to the proposed dwelling. Setbacks are discussed in
further detail in Section 6.2 below.
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6.0 BUSHFIRE IMPACT REDUCTION
6.1 GENERAL
The bushfire hazard assessment undertaken in Section 2 and the Local Hazard Map prepared in Section 3
concluded that the western extent of the Lot 2 building envelope is located within a Potential Impact
Buffer associated with a High Potential Bushfire Intensity area. As the proposed development site has
been confirmed to be located within a bushfire hazard area, measures are required to be implemented to
mitigate impacts associated with bushfire. The measures nominated will reduce the risk of bushfire impact
to people and property and have been determined with reference to:
Noosa Plan 2020 Bushfire Hazard Overlay Code
Natural Hazards, Risk and Resilience –– Bushfire State Planning Policy – state interest guidance
material (The Department of Infrastructure, Local Government and Planning, 2019)
Bushfire Resilient Communities. Technical Reference Guide for the State Planning Policy State
Interest ‘Natural Hazards, Risk and Resilience - Bushfire’ (Queensland Fire and Emergency
Services, 2019)
6.2 SETBACKS
Assessment Benchmark 4 of the State Planning Policy (SPP) – state interest guidance material requires
that development supports, and does not hinder, disaster management response or recovery capacity or
capabilities. 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 (29kW/m2) or less. Quantitative modelling using Flamesol software has been
undertaken to identify the setback requirements to achieve the <29kW/m² radiant heat flux SPP
requirement. The Flamesol setback modelling has determined that a minimum separation of 20.1m is
required to achieve the <29kW/m2 radiant heat requirement. The full Flamesol transcript has been
provided as Appendix B.
The Lot 2 building envelope fronts hazardous vegetation to the west of the site, and it has been provided
with a 60m setback to the adjacent hazardous vegetation. This setback is adequate to provide the future
dwelling a sufficient cleared setback to the adjoining hazardous vegetation in excess of the minimum
setback required to achieve the <29 kW/m² radiant heat flux SPP requirement.
To ensure that the minimum setback is available to the new dwelling in perpetuity, it is recommended
that the dwelling be provided with a dedicated 21m wide Asset Protection Zone to the west of the Lot 2
dwelling. The 21m setback is to be maintained as a dedicated Asset Protection Zone (APZ) in accordance
with the design criteria specified in Section 6.2.1 below. The provision of a dedicated managed APZ will
ensure that the dwelling is provided with sufficient setback into the future, even if the western extent of
the allotment is allowed to regrow with native vegetation.
6.2.1 Asset Protection Zone Design
Landscaping within the 21m wide APZ shall comprise species that are characterised by minimal fuel
generation and is to satisfy Assessment Benchmark 7 of the SPP Bushfire 2019. Assessment Benchmark 7
of the SPP Bushfire 2019 states that where a requirement for an asset protection zone exists, landscaping
treatments are to comprise only low threat vegetation such as grassland managed in a minimal fuel
condition, maintained lawns, vineyards, orchards, cultivated gardens, nature strips and/or windbreaks.
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OR
Landscaping management maintains a potential available fuel load which is less than eight tonnes/hectare
in aggregate, and fuel structure which is discontinuous.
OR
Development includes a bushfire management plan for the maintenance of any identified asset protection
zone, including landscape design and ongoing vegetation management.
To reduce the potential for bushfire impact to the Lot 2 dwelling as a result of future landscaping,
regrowth and fuel load accumulation within the site, the 21m APZ is to be established and maintained
according to the following criteria:
The APZ is maintained as a low threat zone dominated by a maintained grassy surface cover to a
nominal 100mm height which is regularly mowed to reduce fuel loads and the risk of a grassfire
encroaching toward the building
Any landscaping within the APZ satisfies the low threat vegetation criteria prescribed in section
2.2.3.2 of AS3959:2018 and be planted as discrete isolated clumps of low flammability vegetation
aligned parallel to the building to aid in interception of ember and smoke attack and not
perpendicular and in a manner which could transmit fire toward the building
No trees or large shrubs are to be retained or planted within 10m of the building and no tree limbs
are to extend to within 6m of the roof line
No woody mulch is to be used within 2m of the church building
Landscaping only incorporates locally indigenous, low flammability species and or low density
plantings of suitable open forest /woodland species with low bark shedding characteristics
Surface fuels and woody regrowth be controlled in the APZ to maintain a low fuel load
environment. Roof tops, roof gutters and other areas of the building are to be regularly inspected,
and debris removed to reduce the risk of spot fires developing during a bushfire event
In accordance with Assessment Benchmark 7 of the SPP Bushfire, the APZ is to be designed to
ensure a potential available fuel load is maintained at less than 8 tonnes/hectare in aggregate and
with a fuel structure that remains discontinuous.
6.3 FIREBREAKS
A risk of fire impact has been identified from the west of the site. The proposed new allotment adjoins
the hazardous vegetation to the west; however, approximately 60m of cleared open space is located
between the proposed building envelope and the vegetation to the west. Furthermore, the new Lot 2
dwelling is to be provided with a minimum 21m dedicated APZ consisting of cleared grassed separation
to the west of the new dwelling. The allotment is located on flat land and is generally cleared of
vegetation, hence offers suitable operating conditions for emergency services with excellent exposure to
the forest edge to the west. Therefore, no formal firebreaks are considered necessary. The development
will rely on the other bushfire risk management measures detailed within this management plan to reduce
the bushfire risk to an acceptable level.
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6.4 WATER SUPPLY
The proposed development will not be connected to a reticulated water supply. As per Acceptable
Outcome 3.2 of the Noosa Plan Bushfire Hazard Overlay Code, where there is no available reticulated
water supply, the premises has:
a) an accessible dam, swimming pool or water tank available for firefighting purposes with an onsite water
volume of not less than 5,000 litres; and
b) a water supply outlet pipe 50 millimetres in diameter fitted with a standard fire brigade fitting
connected to the water supply (other than where the water supply is in a swimming pool or dam).
A permanent dam with volume far in excess of 5,000 litres is located approximately 60m to the east of
the proposed Lot 2 building envelope. The existing formed access track traverses immediately adjacent to
the dam and a concrete culvert crossing provides a solid access point for water extraction for fire-fighting
purposes.
Plate 8: Water supply point
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6.5 VEHICULAR ACCESS
Assessment Benchmark 4 of the SPP Bushfire 2019 states that to facilitate safe evacuation during a
bushfire event, a development footprint plan should be 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 percent. The proposed Lot 2 driveway access is approximately 300m
long. The access easement is 10m wide and the driveway would direct occupants through an area of low
hazard vegetation in an easterly direction and away from the likely direction of a fire front to the west of
the site. The site is on low grade and the allotment is of sufficient size to provide adequate turning space
for fire-fighting appliances. Whilst Lot 2 cannot comply with the 60m distance as recommended in
Assessment Benchmark 4 of the SPP, it is considered acceptable in this instance as the driveway is on low
grade and directs occupants through a low hazard area away from the likely direction of a fire front.
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7.0 NOOSA PLAN 2020 – BUSHFIRE HAZARD OVERLAY CODE
The proposed development is considered assessable development and therefore is assessable against
Table 8.2.3.3 Bushfire Hazard Area of Council’s Part 8.2.3 Bushfire Overlay Code which has been
reproduced as Table 2.
Note - Under Chapter 2, Part 1, Section 8, Item 4(a) of the Planning Act 2016, where there is an
inconsistency between a State planning policy and local government planning instrument, a State planning
policy applies instead of a regional plan or local planning instrument. Therefore, the State Planning Policy
– Natural Hazards, Risk and Resilience assessment benchmarks supersede the outcomes prescribed in the
Council Code where they involve the same elements.
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Table 2 – Table 8.2.3.3 Bushfire Hazard Areas – Part 8 Overlay Code Noosa Plan 2020
PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
Safety of people and property
PO1 AO1.1 This Bushfire Hazard Assessment and Management
Development maintains the safety of Development which will materially increase the number Plan has been prepared to maintain the safety of
people and property from the adverse of people living or congregating on premises, including people and property from the adverse impacts of
impacts of bushfire. reconfiguring a lot, is not located within a medium or bushfire.
high bushfire hazard area.
AO1.1 – The proposed new dwelling is located outside
of the mapped high bushfire hazard area as depicted on
AO1.2
the Local Hazard Area Map (refer to Figure 3).
Development maximises setbacks from hazardous
vegetation to achieve an acceptable risk.
AO1.2 – The proposed Lot 2 building envelope is
located approximately 60m from the offsite vegetation
Editor’s Note —PSP8 Natural Hazards provides
to the west. To minimise risk of encroachment due to
guidance for assessing bushfire hazard risk and
future regrowth within the site, it is recommended that
preparing a bushfire hazard management plan.
the Lot 2 dwelling be provided a 21m dedicated Asset
Protection Zone between the proposed new dwelling
and the hazardous vegetation located to the west. This
setback is the equivalent to achieving compliance with
Assessment Benchmark 4 of the SPP and achieves an
acceptable risk where the additional bushfire
mitigation measures detailed within this report are
employed.
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PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
Impact on Ecologically Important Areas
PO2 No acceptable outcome provided No vegetation clearing or other ecological impacts are
Bushfire mitigation measures do not required to facilitate the bushfire mitigation measures
adversely impact on: detailed in this report.
a) biodiversity values, connectivity and
ecosystem functioning; and
b) the long term physical integrity of
waterways, wetland and areas of native
vegetation.
Water Supply for Fire Fighting Purposes
PO3 AO3.1 The development complies with AO3.2.
Development provides an adequate Premises are connected to the reticulated water supply.
The site will not be connected to a reticulated water
water supply for firefighting purpose
supply. A permanent dam with volume far in excess of
which is reliable, safely located and freely Editor's note—For reconfiguring a lot, water supply
5,000 litres is located approximately 60m to the east of
accessible. needs to provide for a minimum flow and pressure of
the proposed Lot 2 building envelope. The existing
10 litres a second at 200kPa at all times for firefighting
formed access track traverses immediately adjacent to
purposes.
the dam and a concrete culvert crossing provides a solid
access point for water extraction for fire-fighting
OR
purposes.
AO3.2
Where there is no available reticulated water supply,
the premises has:
a) an accessible dam, swimming pool or water tank
available for firefighting purposes with an onsite water
volume of not less than 5,000 litres; and
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PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
b) a water supply outlet pipe 50 millimetres in diameter
fitted with a standard fire brigade fitting connected to
the water supply (other than where the water supply is
in a swimming pool or dam).
Editor’s Note—Water supply capacity for firefighting
purposes is in addition to water supply capacity for
other uses and activities on the premises.
Essential Community Infrastructure
PO4 AO4.1 PO4 - The proposed development does not involve
Essential community infrastructure is able Development involving essential community essential community infrastructure.
to function effectively during and infrastructure is not located within a medium or high
immediately after bushfire events. bushfire hazard area.
OR
AO4.2
Where located in a medium or high bushfire hazard
area, development involving essential community
infrastructure is designed to function effectively during
and after a bushfire event in accordance with a Bushfire
Hazard Management Plan.
Editor’s Note— PSP8 Natural Hazards provides
guidance for assessing bushfire hazard risk and
preparing a bushfire hazard management plan.
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PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
Hazardous Material
PO5 AO5 PO5 - The proposed development does not involve the
Public safety and the environment are not Hazardous materials are not manufactured or stored in manufacture or storage of hazardous materials in bulk.
adversely affected by the impacts of bulk in a bushfire hazard area.
bushfire on hazardous materials
manufacturing or storing in bulk.
Access and Evacuation Routes
PO6 AO6.1 PO6 - N/A – No new roads are proposed. The proposed
Roads provide for easy and safe The road layout provides for through-roads and avoids Lot 2 driveway access is approximately 300m long. The
evacuation of residents of premises and cul-de-sacs and dead-end roads. access easement is 10m wide and the driveway would
access by emergency services. OR direct occupants through an area of low hazard
AO6.2 vegetation in an easterly direction and away from the
The development has a perimeter road reserve with a likely direction of a fire front to the west of the site. The
minimum width of 20 metres and maximum gradient of site is on low grade and the allotment is of sufficient
12.5%. size to provide adequate turning space for fire-fighting
OR appliances. Whilst Lot 2 cannot comply with the 60m
AO6.3 distance as recommended in Assessment Benchmark 4
Cul-de-sacs or no-through roads are provided with fire of the SPP, it is considered acceptable in this instance
trails or access easements, which are capable of being as the driveway is on low grade and directs occupants
navigated by conventional vehicles and which link to through a low hazard area away from the likely
through roads. direction of a fire front.
AO6.4
Safe access and egress is available at all times to all of
the development for emergency vehicles and
personnel.
AO6.5
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PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
Where an emergency access point is required, it
complies with the relevant works codes and PSP6
Engineering Design Standards.
Lot design
PO7 AO7 PO7- The building envelope has been located within the
Lot design and building siting minimises Each residential lot: lowest hazard area and has been provided with
bushfire hazard risk to people and a) includes a building envelope, identified on a plan of sufficient separation to confirmed hazardous
property. subdivision; vegetation to secure a likely BAL 12.5 construction
standard under AS3959.
b) is of sufficient size and shape to allow for efficient
emergency access to buildings for firefighting
appliances (e.g. by avoiding battle-axe/hatchet lots and
long narrow lots with long access driveways to
buildings);
c) where more than 2500m², achieves setbacks from
hazardous vegetation in line with Bushfire Attack Level
29 requirements as per AS3959; and
d) is designed so that buildings and structures are sited
in locations of lowest hazard within the lot and
elements of the development least susceptible to fire
are closest to the fire hazard.
Firebreaks and fire access tracks
A08.2 – No specific fire breaks are proposed to be
PO8 AO8.1
constructed. The building envelope has been provided
Firebreaks and fire access tracks provide: Where development involves the creation of a new
with a minimum 21m dedicated APZ consisting of
road and lots, a firebreak is provided by providing a
cleared grassed separation to the hazardous vegetation
cleared road reserve not less than 20 metres wide and
a) adequate access for firefighting and to the west. The allotment is located on flat land and is
maximum gradient of 12.5% around the perimeter of
other emergency vehicles; and generally cleared of vegetation, hence offers suitable
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PERFORMANCE OUTCOMES ACCEPTABLE OUTCOMES PROPOSED SOLUTION
b) adequate access for the evacuation of the subdivision, between the created lots and operating conditions for QFES with excellent exposure
residents and emergency personnel in an surrounding vegetated lands. to the forest edge to the west. Therefore, no formal
emergency situation. OR firebreaks are considered necessary. The development
AO8.2 will rely on the other bushfire risk management
Fire access tracks are provided between the created measures detailed within this management plan to
lots and surrounding vegetated land that: reduce the bushfire risk to an acceptable level.
a) have a cleared minimum width of 6 metres;
b) have a maximum gradient of 12.5%;
c) provide unbroken access for fire fighting vehicles;
d) provide passing bays and turning areas;
e) are located within an access easement that is
granted in favour of Noosa Council and the Queensland
Fire and Rescue Service.
AO8.3 AO8.3 – All bushfire management measures prescribed
Bushfire management measures are carried out on the herein would be carried out on the subject property
subject property and not any adjoining property. and not rely upon any adjoining property.
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8.0 CONCLUSION
A bushfire hazard assessment has been completed for Lot 46 on RP136461 located at 21 Jirrima Crescent,
Cooroibah, and has identified that the vegetation to the west of the site comprises an overall risk rating
of a High Potential Bushfire Intensity hazard. The proposed development area is located within a Potential
Impact Buffer associated with the adjacent High Potential Bushfire Intensity area. The hazardous
vegetation to the west is located upwind of the site under typical seasonal fire winds, therefore the site
is deemed to be exposed to a likely probability of bushfire impact. Approximately 60m separation is
available between the proposed building envelope and the hazardous vegetation to the west.
Furthermore, this assessment has recommended that a 21m Asset Protection Zone be provided to the
new dwelling within Lot 2 to ensure the separation is available in perpetuity. The Asset Protection Zone
will provide the new dwelling a distance sufficient to achieve less than 29kW/m2 radiant heat impact. The
setbacks provided are considered to reduce the level of bushfire risk to the proposed development to an
acceptable level.
Bushfire impact reduction measures have been recommended in line with Noosa Planning Scheme and
the relevant Assessment Benchmarks detailed in the Natural Hazards, Risk and Resilience –– Bushfire State
Planning Policy – state interest guidance material 2019. Implementation of the recommendations
detailed in this Bushfire Management Plan is considered to provide a reasonable level of protection for
people and property within the site and reduce the overall risk of bushfire impact to an acceptable level.
Bushfire can be unpredictable and requires adequate preparatory planning and actions to be undertaken
to minimise impacts to property and potential loss of life. This assessment has been prepared with
consideration of site conditions observable at the time of inspection, the distance between the proposed
development and potentially hazardous vegetation, the extent of fragmentation occurring within the
landscape and the nature of the development proposed. The hazard assessment methodologies
described in this report are not based on assessments of catastrophic bushfire events which may occur
from time to time. The unpredictable nature of bushfires prevents any guarantee being provided that the
area will not be affected by bushfire at some time. Property owners and site users should be aware of the
potential consequences of such events and should take responsibility for the protection of property and
personnel accordingly.
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9.0 REFERENCES
Leonard, J., Opie, K. (2017). Estimating the potential bushfire hazard of vegetation patches and corridors.
An enhancement of Queensland’s methodology for State-wide mapping of bushfire prone areas. CSIRO
Land & Water, Australia.
Queensland Fire and Emergency Services. (2019). Bushfire Resilient Communities - Technical Reference
Guide for the State Planning Policy - State Interest Guideline - Natural Hazards, Risk and Resilience 2-
Bushfire.
The State of Queensland, Department of State Development, Manufacturing, Infrastructure and Planning
(2019). Natural hazards, risk and resilience - Bushfire State Planning Policy – state interest guidance
material.
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APPENDIX A – PLAN OF DEVELOPMENT
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Scale 1:2000 - Lengths are in Metres
DENOTES AREA SUBJECT TO
RIPARIAN BUFFER OVERLAY
20 0 20 40 60 80 100 120 140 160 180 200 220
DENOTES AREA BELOW 1%
AEP PEAK FLOOD LEVELS
(2100 CLIMATE)
MAX WATTERSON
+ASSOCIATES
CONSULTING SURVEYORS
& PLANNERS
2
2
3
4
12 Maple Street
5 PO Box 639
Cooroy Qld 4563
6
Ph. (07) 54426121
Fax. (07) 54425125
Email. [email protected]
Client: I. ROWE
7
47 Project:
102
8
RP136461
SP208642 PLAN OF PROPOSED
RECONFIGURATION
SCENT
OF LOT 46 ON
126.34
9
10m Emt A
Proposed Easement SP315440 RP136461.
8 for Access & Service
04.5 s 10m wide 302.62
1
2
10
103 1
1.824ha
JIRRIMA CRE
Single Storey
.4
29.9
House
HOUSE SITE
AREA
2.567ha
9
95.55
249.38 Garage
10m LOCAL GOVT: NOOSA S.C.
LOCALITY: COOROIBAH
249.02
101
5
Plan 1 of 1
SP191688 Scale: 1:2000
Date: 18-11-21
Datum: AHD
45 Origin: NSC
Mapping
RP136461
Cont.Int: 1.0m
Ref:
21-5581AA
NOTE:
3
This plan has been prepared for application
purposes only and may be subject to change.
3
10
Dimensions and areas shown hereon are
approximate only and subject to final survey.
3
4
6
9
7
8
8
7
6
7
6
8
5
Page 36
APPENDIX B – Flamesol Modelling
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