EASTERN BEACHES FORESHORE RESERVES MANAGEMENT PLAN - COMMUNITY CONSULTATION OVERVIEW AND PROPOSED CHANGES (Referred from Planning and Environment Committee dated 8 August 2023 - Item 5.1) · Attachment 2 EBFRMP 2023 Draft - tracked changes

study are to: 1) monitor water quality, 2) monitor the 2D and 3D morphological change of the creek;
3) relate the observed changes in water quality and morphology to boundary conditions (e.g.,
waves, the creek’s water surface level, rainfall, and discharge), and 4) develop an empirical model
to predict triggers forcing changes in water quality and the creek’s morphology.

Morphology: The creek’s planform change, channel depth and beach/dune volumetric changes
will be surveyed using drone photogrammetry and satellite profiles on a monthly and/or event-
driven basis (e.g., before/after significant swell or rainfall events). Nearshore hydrodynamics
(waves and currents) will be modelled using a calibrated wave simulation model. An XBeach model
will be used to model beach/dune volumetric changes and tested using observed data.

Water levels and flows: The creek’s water surface level will be monitored using a pressure sensor
at the mouth (west side of the bridge) based on significant events (e.g., during significant weather
). The creek’s flow velocity will be continuously monitored (every 30 seconds) using a water flow
meter at a fixed site (west side of bridge). Flow data will be uploaded daily and will be accessible to
Noosa Council via UniSC’s online data account. The channel’s morphology will be surveyed to
estimate the creek’s discharge based on monitored flow.

Water Quality: Water quality samples will be collected at the same site west of the bridge, and the
outflow site (Wallum Lane – Rotary Way, Noosa Sewerage Treatment Plant) monthly or after
significant events (>20mmm rainfall), and tested for concentrations of e.coli, total nitrogen, total
phosphorus and total suspended solids.

Decision making tool: A stage/discharge relationship or rating curve will be developed for the
creek, and data will be collated and analysed to develop an empirical model that will explain the
main triggers and predict thresholds that force the creek’s morphological and water quality
changes.

The practical and easy to use decision support tool based on the empirical model developed from
this project will benefit the management of Burgess Creek by determining the thresholds best
suited for actions. For example, the tool could be used to determine when is best/necessary to
open the creek’s mouth to mitigate dune erosion or when the creek’s water quality could be
expected to be a health hazard.

Burgess Creek Integrated Catchment Management Plan (Future budget proposals)
An Integrated Catchment Management Plan (ICMP) for Burgess Creek project is being developed
by the Infrastructure and Environment Services branches. It will establish a framework for its
sustainable management and facilitate investigation of the catchment.
The Burgess Creek ICMP will
    •       Investigate current hydrology, stream flow behaviour, groundwater flows, 3rd party
            flows and bank stability
    •       Collate the ecological values of Burgess Creek and how these are being impacted
    •       Undertake water quality investigations to determine:
    •       Impacts of point and diffuse sources water quality issues within Burgess Creek
    •       Compliance with Department of Environment & Science water quality objectives
    •       Impact of historical landfills, rapid infiltration basins and night soil disposal areas on
            groundwater
    •       Compliance with the Recreational Health Guidelines

Coastal creek mouth realignment (Ongoing)
The lowest reach of some coastal creeks, where they cross the beach, are periodically realigned,
dependant on the extent of creek mouth movement and impact on adjacent dunes or beach access
infrastructure. Burgess Creek mouth has been realigned four times in the last two financial years.
This is completed by Council under an ongoing permit for coastal works.


Eastern Beaches Foreshore Reserves Management Plan 2023                                       Page 102