LUSH FIRE & PLANNING 3 Paterson Road

Pinjarra WA 6208 ABN 74 232 678 543

Bushfire Attack Level (BAL) Assessment Report Exbury Lane Wentworth West

Report Details

Job No Report Version Assessment Date Report Date

19-031 A 20 May 2019 24 May 2019

Property Details

Street No Lot No’s Plan Street Name

10, 14, 24 &

26

92, 94, 99 & 100

411219 Exbury Lane

Locality Success State WA Postcode 6164

Local Government Area Cockburn

Description of the building or works

Residential Lots

Accredited Practitioner Details

Name Bushfire Planning and Design (BPAD) Accreditation Number

G Lush Level 2 Bushfire Planning Practitioner BPAD27682

Name Geoffrey Lush

Authorised Practitioner Stamp

Company Details 3 Paterson Rd Pinjarra WA 6208 0418954873 geoffrey@lushfire.com.au

Reliance on the assessment and determination of the Bushfire Attack Level contained in this report should not extend beyond a period of 12 months from the date of issue of the report. If this report was issued more than 12 months ago, it is recommended that the validity of the determination be confirmed with the Accredited Practitioner and where required an updated report issued.

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Background

This report is prepared for Richard Noble & Company to support the development of Lots 92, 94, 99 and 100 Exbury Lane, Wentworth West Estate Success. The property details are as follows:

No Lot Plan Volume Folio Registered Proprietor Area (m2)

10 92 411219 2924 152 Gold Estates Holdings Pty Ltd 224

14 94 411219 2924 154 Gold Estates Holdings Pty Ltd 224

24 99 411219 2924 159 Gold Estates Holdings Pty Ltd 209

26 100 411219 2924 160 Gold Estates Holdings Pty Ltd 204

All of the subject land is defined as being bushfire prone and this triggers the application of Australian Standard AS3959 Construction of Buildings in Bushfire Prone Areas under the Building Code of Australia. A building permit application for any new dwelling in a bushfire prone area requires that a Bushfire Attack Level (BAL) Assessment be undertaken to determine the relevant construction requirements under AS3959 Construction of Buildings in Bushfire Prone Areas. It is noted that the Estate is subject to:

➢ A previous Bushfire Management Plan (BMP) was prepared in June 2015 by TME Town Planning Management Engineering Pty Ltd (Ref 12072) to support the subdivision application; and

➢ An approved Local Development Plan - Wentworth West Stage 3.

The subject land has an R40 Residential Density Coding. The Local Development Plan requires:

• Outdoor living areas are encouraged in the setback area adjacent to the POS for lots 88 - 101; and

• Dwellings on lots 88 - 101 must be orientated to address the POS with major openings from a habitable room.

The rear boundary setback is to be determined in accordance with Table 2b: Boundary setbacks - Walls with major openings of the Residential Design Codes (R-Codes). For a wall height of 3.5m or less and a wall length of 9m or less the setback requirement is 1.5m. For the purpose of this BAL Assessment the 1.5m setback has been used to define the development area within the lots.

Explanatory Notes

The Bushfire Attack Level (BAL) Assessment measures the severity of a buildings potential exposure ember attack, radiant heat and direct flame contact in a bushfire event. Each BAL rating corresponds to different construction requirements and provisions. The Bushfire Attack Level (BAL) Assessment measures the severity of a buildings potential exposure ember attack, radiant heat and direct flame contact in a bushfire event. The BAL rating is determined through the identification and assessment of the following parameters:

• Fire Danger Index (FDI) rating; assumed to be FDI – 80 for Western Australia;

• All classified vegetation within 150m of the subject building;

• Separation distance between the building and the classified vegetation source/s; and

• Slope of the land under the classified vegetation. AS3959:2018 has six (6) levels of BAL, based on the radiant heat flux exposure to the building, and also identifies the relevant sections for building construction as detailed in Table 1.

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Table 1 BAL Ratings

Bushfire Attack

Level (BAL)

Classified vegetation within 100m of the site and heat flux exposure

thresholds

Description of predicted bushfire attack and levels of exposure

BAL-LOW See clause 2.2.3.2 There is insufficient risk to warrant any specific construction requirements.

BAL-12.5 ≤ 12.5kW/m2 Ember attack

BAL-19 > 12.5kW/m2 to ≤ 19kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux.

BAL-29 > 19kW/m2 to ≤ 29kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux.

BAL-40 > 29kW/m2 to ≤ 40kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux with the increased likelihood of exposure to flames.

BAL-FZ > 40kW/m2 Direct exposure to flames from fire front in addition to heat flux and ember attack.

The applicable BAL construction measures do not guarantee that a building will survive a bushfire event on every occasion. This is substantially due to the degree of vegetation management, the unpredictable nature and behaviour of fire and extreme weather conditions.

Site Assessment

The assessment of this site / development was undertaken on 20 May 2019 by a BPAD Accredited Practitioner for the purpose of determining the Bushfire Attack Level in accordance with AS 3959 - 2018 Simplified Procedure (Method 1). All vegetation within 150m of the site / proposed development was classified in accordance with:

• Clause 2.2.3 of Australian Standard AS3959 Construction of Buildings in Bushfire Prone Areas;

• The Visual Guide for Bushfire Risk Assessment in Western Australia; and

• Applicable Fire Protection Australia BPAD Practice Notes.

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Site Assessment

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Photograph Locations

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Photo No 1 Plot No 1

Vegetation Classification

Class A Forest - Low open forest A-

04

Description

Melaleuca vegetation to 10m height in the swamp area. It is technically closed as the foliage coverage is 90% but this does not comply with Class 18. Very heavy fuel loads. Vegetation is situated on the northern and north eastern side of the fire service access route.

Photo No 2 Plot No 1

Vegetation Classification

Class A Forest - Low open forest A-

04

Description

Melaleuca vegetation to 10m height in the swamp area. It is technically closed as the foliage coverage is 90% but this does not comply with Class 18. Very heavy fuel loads. Vegetation is situated on the northern and north eastern side of the fire service access route.

Photo No 3 Plot No 2

Vegetation Classification

Class B Woodland - Low woodland

B-07

Description

Banksia woodland to 5m with mixed understorey and foliage cover of less than 30%. Moderate to heavy fuel loads. Mixed scrub understorey, overall woodland classification as height exceeds 4m and is expected to increase over time.

Photo size 9cm width

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Photo No 4 Plot No 2

Vegetation Classification

Class B Woodland - Low woodland

B-07

Description

Banksia woodland to 5m with mixed understorey and foliage cover of less than 30%. Moderate to heavy fuel loads. Mixed scrub understorey, overall woodland classification as height exceeds 4m and is expected to increase over time.

Photo No 5 Plot No 3

Vegetation Classification

Class C Shrubland - Low shrubland

C-12

Description

Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

Photo No 6 Plot No 3

Vegetation Classification

Class C Shrubland - Low shrubland

C-12

Description

Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

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Photo No 7 Plot No 3

Vegetation Classification

Class C Shrubland - Low shrubland

C-12

Description

Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

Photo No 8 Plot No 4

Vegetation Classification

Class D Scrub - Closed scrub D-13

Description

Vegetation between the fire service access route and POS area. Predominantly consists of Acacia to 6m height with continuous vertical fuel structure and heavy surface fuels.

Photo No 9 Plot No 4

Vegetation Classification

Class D Scrub - Closed scrub D-13

Description

Vegetation between the fire service access route and POS area. Predominantly consists of Acacia to 6m height with continuous vertical fuel structure and heavy surface fuels.

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Photo No 10 Plot No 5

Vegetation Classification

Class G Grassland – Tussock

grassland G-22

Description

Tussock grassland within the power line easement.

Photo No 11 Plot No 6

Vegetation Classification

Class D Scrub - Open scrub D-14

Description

Revegetation under the transmission line easement. Species not known but the plants in the photo are approximately 1m high and assumed will develop into scrub over time.

Photo No 12 Plot No 7

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Vacant Lot 102 with minimal grass coverage.

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Photo No 13 Plot No 7

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Existing residential development on adjacent land.

Photo No 14 Plot No 7

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Subdivision construction on adjacent land.

Photo No 15 Plot No 8

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Maintained public open space adjacent to the subject land.

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Photo No 16 Plot No 8

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Maintained public open space adjacent to the subject land.

Photo No 17 Plot No 8

Vegetation Classification

Excludable - 2.2.3.2(f) Low Threat

Vegetation

Description

Maintained public open space adjacent to the subject land.

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Relevant Fire Danger Index

The fire danger index for this site has been determined in accordance with AS3959 Table 2.1 or otherwise determined in accordance with a jurisdictional variation applicable to the site.

Fire Danger Index

FDI 40 FDI 50 FDI 80 FDI 100

Table 2.4.5 Table 2.4.4 Table 2.4.3 Table 2.4.2

Potential Bushfire Impacts

The potential bushfire impact to the site / proposed development from each of the identified vegetation plots are identified below. The Determined Bushfire Attack Level (highest BAL) for each site / proposed development has been determined in accordance with clause 2.2.6 of AS 3959-2018 using the above analysis.

LOT 100 (26) EXBURY LANE

Plot Vegetation Classification Effective

Slope

Separation (m) BAL

Lot 1.5m Rear

Setback

P1 Class A - Forest Flat 30m 31.5m BAL – 19

P2 Class B Woodland Flat 16m N/A BAL – 29

P3 Class C Shrubland Flat 12m 13.5 BAL – 19

P4 Class D Scrub Flat 28m 29.5 BAL – 12.5

P5 Class G Grassland Upslope 65m N/A BAL – LOW

P6 Class D Scrub Upslope 77m N/A BAL – 12.5

P7 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

P8 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

Lot 100 - Bushfire Attack Level BAL – 29

LOT 99 (24) EXBURY LANE

Plot Vegetation Classification Effective

Slope

Separation (m) BAL

Lot 1.5m Rear

Setback

P1 Class A - Forest Flat 30m 31.5m BAL – 19

P2 Class B Woodland Flat 23m N/A BAL – 19

P3 Class C Shrubland Flat 16m 17.5 BAL – 19

P4 Class D Scrub Flat 20m 21.5 BAL – 19

P5 Class G Grassland Upslope 65m N/A BAL – LOW

P6 Class D Scrub Upslope 77m N/A BAL – 12.5

P7 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

P8 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

Lot 99 - Bushfire Attack Level BAL – 19

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LOT 94 (14) EXBURY LANE

Plot Vegetation Classification Effective

Slope

Separation (m) BAL

Lot 1.5m Rear

Setback

P1 Class A - Forest Flat 42m 43.5m BAL – 12.5

P2 Class B Woodland Flat 80m N/A BAL – 12.5

P3 Class C Shrubland Flat 16m 17.5 BAL – 19

P4 Class D Scrub Flat 18m 19.5 BAL – 19

P5 Class G Grassland Upslope 92m N/A BAL – LOW

P6 Class D Scrub Upslope 88m N/A BAL – 12.5

P7 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

P8 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

Lot 94 - Bushfire Attack Level BAL – 19

LOT 92 (10) EXBURY LANE

Plot Vegetation Classification Effective

Slope

Separation (m) BAL

Lot 1.5m Rear

Setback

P1 Class A - Forest Flat 42m 43.5m BAL – 12.5

P2 Class B Woodland Flat 97m N/A BAL – 12.5

P3 Class C Shrubland Flat 20m 21.5 BAL – 12.5

P4 Class D Scrub Flat 22m 23.5 BAL – 19

P5 Class G Grassland Upslope 103m N/A BAL – LOW

P6 Class D Scrub Upslope 97m N/A BAL – 12.5

P7 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

P8 Excludable – Clause 2.2.3.2(f) N/A N/A N/A BAL – LOW

Lot 92 - Bushfire Attack Level BAL – 19