Attachment 3 - Additional Information Barlow Shelley

Our Reference: 1443

20 August 2018

Adamson Town Planning
PO Box 78
Peregian Beach, QLD 4573

via email: [email protected]



Dear Shane,


RE:      REVIEW OF COUNCIL EMAIL (27 June 2018)
         FOR PROPOSED RECONFIGURATION OF LOT
         AT 20 MITTI STREET, NOOSA HEADS.

As requested, we have undertaken a review of the comments that Noosa Shire Council’s
planner Kerri Coyle has provided in her email to Martoo Consulting dated 27 June 2018,
as attached to this correspondence, and provide the following comments on the technical
engineering aspects.


Item 1
The flood report suggests that only 30% of the total catchment flow will drain
through the site but there is no detail of how this has been determined. A review
of the LiDAR ground level DEM of the area suggests most, if not all, of the total
catchment runoff is likely to drain through the site.

Section 6.1 of the Flood Hazard Assessment Report (FHAR) states – “The hydrology of
the site is composed of the 31.4-hectare upstream catchment to the southeast of the
site (Refer Appendix A). The upstream catchment was determined by current
LiDAR survey and is comprised of the Noosa National Park and upstream existing
residential development.”

Section 6.2 further states – “A full-scale model for the entire overland flow path was
used to extract the flow conveyed via the overland flow path through the site, which was
found to be 2.611m3/s, which is approximately 30% of the total flow from the upstream
catchment.”

Appendix A of the FHAR includes an Upstream Catchment Plan which demonstrates the
contours and catchment areas above the subject site.

Figure 7.2 from the FHAR (below) shows a partial section of approx. 14m width through
the site to demonstrate the flow depths within the subject site only. A full cross section
from our modelling is also included below as Figure A with the two parts of the
residence represented as high spikes in the cross sections.


1443-03 – Mitti Street, Noosa Heads                                                          1
TS/ts