Compiled Plans & Documents OPW18-0342 02

                                                                Retirement Living & Aged Care Facility
                                                                       Grasstree Court, Sunrise Beach


6           Site-based Bushfire Hazard Assessment
6.1         Methodology
The following assessment was carried out in accordance with the broad methodology underpinning
AS3959 – Construction of Buildings in Bushfire Prone Areas, in the absence of any State-based or
locally-applicable site assessment guidelines.

A range of instruments have been utilised to perform a desktop analysis to complement available
site data. These instruments include:

     •    Original LandGraphics BMP dated 2008;

     •    RPS Bushfire Peer Review Report dated 2016;

     •    Local and State bushfire hazard mapping;

     •    Ecological project data;

     •    State-based vegetation (RE) mapping;

     •    Proposal plans and supporting documentation, etc.;

     •    Vegetation management and landscaping plans;

     •    Aerial imagery;

     •    QFES RediPortal Mapping Platform;

     •    State Planning Policy - Fit-For-Purpose Approach to Undertaking Natural Hazard Studies and
          Risk Assessments Technical Manual; and

     •    AS3959-2009 – Construction of Buildings in Bushfire Prone Areas.

A site inspection was undertaken on Wednesday 26 September 2018 under fine, fire season weather
conditions. At the time of this site inspection, preceding rainfall had been low to moderate with
temperatures not dissimilar to typical early winter averages.

6.2         Fire Weather
In terms of assessment methodology, it is noted the Forest Fire Danger Index (FFDI) adopted by
AS3959-2009 for Queensland is 40 with a flame temperature of 1,090k. However, recent research has
determined the fire weather in South East Queensland is higher than that identified under AS3959-
2009. The State Planning Policy mapping methodology developed by CSIRO identifies this area of
South East Queensland as subject to an FFDI ranging between 40 and 50. The QFES RediPortal
indicates an estimated 1 in 20 year FFDI for this area of South East Queensland at approximately 48,
which was also canvassed by RPS in its 2016 Bushfire Peer Review reporting submitted to Council
with the approval extension request. To this end, an FFDI of 48 is adopted for the purposes of this
assessment. This remains higher than the FFDI adopted by both the current and draft version of AS
3959.

In considering the above, it is important to understand the frequency of more extreme fire weather
days in South East Queensland. The number of days per decade on which an FFDI of 50 (Severe) is
exceeded is 11.7 days, and an FDI of 75 (Extreme to Catastrophic) is exceeded only 0.9 days of
each decade (Lucas, 2007). The influence of climate change may alter these statistics into the
future however at present, this data accurately indicates the current risk profile prosed by such fire
weather conditions.




Status: Final                                                                                March 2019
Project No.: 18-030                                                                             Page 25