Attachment 4B - Updated Bushfire Assessment and Mitigation Plan.pdf

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                 Inputs                                   Outputs
    Vegetation height n/a           Fire intensity           21,888 kW/m
    Effective slope     8°          Transmissivity           0.872, 0.854, 0.828, 0.803,
                                                             0.79 & 0.728
    Site slope          1°          Viewfactor               0.599, 0.4456, 0.3007,
                                                             0.2045, 0.1663 & 0.0451
    Flame width         100 m       Minimum distance to <               11.7 m
                                    40 kW/m²
    Windspeed           n/a         Minimum distance to <               15.7 m
                                    29 kW/m²
    Heat of             18,600      Minimum distance to <                23 m
    combustion          kJ/kg       19 kW/m²
    Flame               1,090 K     Minimum distance to <               32.4 m
    temperature                     12.5 kW/m²
                                    Minimum distance to <               38.4 m
                                    10 kW/m²
     Rate of Spread - Mcarthur, 1973 & Noble et al., 1980
     Flame length - NSW Rural Fire Service, 2001 & Noble et al., 1980
     Elevation of receiver - Douglas & Tan, 2005
     Flame angle - Douglas & Tan, 2005
     Radiant heat flux - Drysdale, 1999, Sullivan et al., 2003, Douglas & Tan, 2005

The setback distance required to achieve a radiant heat flux of less than 29kW/m2 is 15.7m
from the potentially hazardous vegetation to the north. Figure 4 below designates the
setback edge of hazardous vegetation where the distance to the proposed building is 21.9m
from the north-eastern most corner, and 24.4m from the north-western most corner. This will
achieve a Radiant Heat Flux within 19-29kW/m2 which is within the sates acceptable level of
risk. Compliance with AS3959-2018 for a Class 3 Structure will be required.



Figure 4:- Proposed development location opposite potentially hazardous
vegetation. A setback distance from the nominal ‘Hazardous Vegetation
Effective Edge Line’ of 15.7m will achieve a Radiant Heat Flux less than
29kW/m 2 . The actual distance of the proposed development to hazardous
vegetation is 21.9m.

NOTE – the building location has been overlaid over a 2020 aerial image and shows the
current tennis courts. These will be removed as part of the site development works as
approved by Noosa Council.




RF17-040 – Boutique Hotel – Noosa Springs – Bushfire Hazard Assessment & Management Plan
Rob Friend & Associates Pty Ltd                                                10 February 2023