RFI - 21370-001-Rev1 66 Seaview Tce

                              PROPOSED RESIDENCE
                              66 SEAVIEW TERRACE, SUNSHINE BEACH

4.7       Surface Drainage
Surface drainage would be expected to follow natural surface contours to the east towards the beach. The
site has a relatively small catchment, with some run-off expected to enter the site from the cul-de-sac head
due to the open unedged frontage to Seaview Terrace. It is anticipated that this would be intercepted by
upgraded verge landscaping, and kerbage along Seaview Terrace as part of the residential development.

Given the sandy nature of the site, rainfall would normally be anticipated to infiltrate the ground surface
relatively quickly. However, as the proposed development will occupy a large part of the block, significant
run-off from hard surfaces will likely occur. Nevertheless, where directed into swales rather than pipes,
such run-off would be expected to infiltrate into the natural sands relatively rapidly. No significant surface
run-off features were noted across the allotment during our assessment (e.g. deep rilling or scour/wash out
scars).

5.0      SLOPE STABILITY ASSESSMENT
5.1      Existing Conditions
The Noosa Planning Scheme 2020 includes a landslide hazard overlay map (Ref. extract in Text Figure 11
below) which indicates that the site is within a Moderate Hazard Area.




                                                               Subject site




Text Figure 11: Extract from Noosa Council landslide hazard overlay mapping

It should be noted that the Noosa Council landslide hazard map is a broad-scale indication of the potential
landslide susceptibility and is superseded by this site-specific assessment. The allotment did not exhibit
any visible surface features which would indicate larger scale significant global slope instability during our
walkover: no landslide back scarps, noteworthy groundwater seepage or areas of naturally ‘hummocky’
ground were observed. Medium dense sands were encountered at relatively shallow depths below
surface, with the high dune standing at between 29° to 33°.




28 April 2022
Report No. 21370-001-Rev1                                10