ATTCH 3 - IR Response - Erosion, Coastal Processes and Stormwater (Dr Trevor Johnson)

14 November 2017 Trevor Johnson

Engineering Consultant
KTLAR Pty Ltd

252 Pacific Parade
BILINGA QLD 4225

Urban Systems By Email
20 Patterson Street
AUCHENFLOWER QLD 4066

Attention: Mr Peter Cumming

Dear Peter

KENLYNN PTY LTD — PROPERTY 2, DAVID LOW WAY, CASTAWAYS BEACH
SPECIALIST ENGINEERING ADVICE TO SUPPORT DEVELOPMENT APPLICATION
RESPONSE TO INFORMATION REQUEST

Introduction

In accordance with your instructions, | have reviewed Council's Information Request of 7 September
2017. The following issues relevant to my areas of expertise are raised in that document:

Issue - Vegetation

1.

Demonstrate the development can provide suitable protection of community assets
including David Low Way, the dune systems, the adjacent vegetation, and
accommodate storm surge, sea level rise, and extreme storm events and allow for
ambulatory changes to the head of Burgess Cree. Include an assessment of the
ongoing use and the impacts on the fore dunes through increased access, whilst not
burdening regulatory services to manage the area.

Issue — Water Quality of Burgess Creek and Stability at Stormwater Outlet Points

9.

10.

11.

Demonstrate that the proposed development will meet the environmental objectives for
water quality management as required by the SPP and The Noosa Plan.

Provide a preliminary stormwater strategy which identifies the proposed stormwater
outlet locations and flow paths as a result of the proposed development.

Provide advice from a suitably experienced and qualified geotechnical engineer to
confirm that the proposed stormwater discharge strategy will not affect stability on
Jandslip areas or cause erosion.

Dealing with item 1 first, vegetation issues will specifically be dealt with separately by Mr John Delaney
on behalf of the applicant. However, | can add some information in respect of the coastal processes
which are mentioned in the item.

The development application included a detailed coastal hazard analysis which demonstrated that the
site would not be affected by coastal processes in the timeframe required to be considered for
development assessment purposes. In particular, the technical assessment showed that the site did
not lie within the coastal erosion zone.

Consequently, it can be stated clearly that there is no impact on the site from storm surge, sea level rise
and extreme storm events.