220328 - Edwards Street - Slope Stability Assessment

Bev Jenner Const.                                                                             22073-001-Rev0
C/- Westera Partners                                                                           25 March 2022

3.0     ASSESSMENT OF LAND STABILITY
3.1   Existing Conditions
The Noosa Planning Scheme 2020 includes a landslide hazard overlay map (Ref. extract in Text Figure 8),
which indicates that isolated parts of the site, including parts of the proposed development areas, are within
a Moderate (pale yellow-brown shading) landslide hazard area.




                                                                             Lot boundary




Text Figure 8: Extract from NC landslide hazard overlay mapping

It should be noted that the Noosa Council (NC) landslide hazard map is a broad-scale indication of the
potential landslide susceptibility and is superseded by site specific investigation and assessment (this
report). No visual signs of global slope instability were not observed across the subject site. Tilting palms
to the southern corner of the block were likely as a result of them being planted at the crest of a sharp
break in slope (from about 9° to 25°). No landslide back scarps or areas of naturally ‘hummocky’ ground
were observed.

Furthermore, it is inferred that the isolated Moderate hazard areas within the NC overlay are more likely
because of localised steepenings as a result of landscaping features (i.e. the dug out area to the southern
corner of the subject block, and sloping, retained garden beds on 166 Edwards Street).

3.2   Stability Assessment
The risk assessment for this project has been carried out following AGS 2007 Practice Note Guidelines for
Landslide Risk Management. Relative levels of risk and their implications are given in Table 1 overleaf and
the Qualitative Terminology for Use in Assessing Risk to Property is also attached.




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