Attachment C - Bushfire Management Plan · 132008.1128.04

                                                              Retirement Living & Aged Care Facility
                                                                     Grasstree Court, Sunrise Beach

6.4         Effective Slope
Effective slope relates to the topography of vegetation beneath classified vegetation, as this
influences fire speed and rate of spread - namely, that the speed of fire doubles for every 10 degrees
incline. An on-site effective slope assessment has been conducted over a distance of 150m via
detail survey, Council and DNRM contour data and verified via site inspection.

The subject land is upslope from all areas of potential bushfire hazard which translates to a slight
upward run of fire on approach to the subject land. These slopes however are not steep but rather,
very gradual and unlikely to generate much increase in fire intensity and behaviour. The downslope
values below reflect those captured by both the original bushfire assessment report prepared by
Land Graphics in 2008 and the RPS peer review assessment conducted in 2016.




                                                      2.0 deg downslope
                                 1.1 deg downslope




                 4.0 deg downslope



                      3.6 deg downslope



                              3.7 deg downslope
                                                     4.0 deg downslope




Figure 15 - Effective slope assessment relating to the subject land (Source: Imagery derived from
DNRM, 2018 with slope values derived from Land Graphics, 2008 and RPS, 2016)

6.5         Aspect
Aspect can affect bushfire behaviour where slopes with northerly and/or westerly aspects
experience a higher level of solar access than those areas with a southern or eastern aspect. This
generally translates to drier fuels with lower moisture content and increased dead/drying/curing
material. Notwithstanding, in times of drought and below average rainfall, moisture levels in soil and
vegetation in more sheltered areas with southerly and easterly aspects can also decrease
substantially giving rise to significantly higher fuel abundance where the preceding fire regime has
been less frequent or intense. Thus, aspect is of only partial consequence in this respect and this is
reflected by the current SPP mapping methodology and information made publicly available by
QFES.

Aspect is also not an element of assessment identified within the current Bushfire Resilient
Communities Guideline.




Status: Final                                                                                  July 2020
Project No.: 18-030                                                                             Page 31