2015-04-28 Planning and Organisation Committee Agenda

PLANNING & ORGANISATION COMMITTEE MEETING AGENDA                                 28 APRIL 2015


Strategic Land Use Planning

9    NOOSA RIVER HYDRODYNAMIC MODEL UPDATE
Author            Principal Strategic Planner, Rebecca Britton
                  Planning & Infrastructure Department

Index             ECM/Subject/Flood Management/Flood Studies

Attachments       Nil


EXECUTIVE SUMMARY
Not applicable.

RECOMMENDATION
That Council note the report by the Principal Strategic Planner to the Planning &
Organisation Committee Meeting dated 28 April 2015 providing an update on the preparation
of a Hydrodynamic Model for the Noosa River.


REPORT
Background

Ongoing erosion of public land and infrastructure assets around the lower reaches of the
Noosa River, including Munna Point, has highlighted the need for better decision making
tools through hydrodynamic modelling to assist Council and the community with future
management of the river.

At Munna Point a sand filled geotextile bag seawall was constructed as emergency works to
protect the holiday park in 2013 following a flood event. To address further erosion risks an
application has been recently submitted by Council to the Department of Environment and
Heritage Protection (EHP) for the construction of sandbag groynes on a trial basis.

Community workshops with river users and discussions with EHP mid last year helped to
formulate a way forward for future river management. It was determined that a hydrodynamic
model for the lower reaches of the Noosa River (from Tewantin to the river mouth) should be
developed to enable predictive modelling of erosion management options and how these
options might affect the movement of sand through the system.

Coupled with this, the Noosa River flood model requires updating. The basis for this model
was developed in 1995 using 1D (one dimensional) modelling. Updating the model using
contemporary 2D (two dimensional) modelling would provide more reliable information on
erosion processes within the river, as well as overland flood velocities and flood levels
across the catchment.

Council has also been approached by Healthy Waterways to partner in the development of a
Pollutant Export Model to simulate the generation of pollutants from catchment land uses
and the transporting and assimilation of these pollutants through the Noosa River system.
Other councils in South East Queensland have carried out similar pollution export modelling
including Moreton and Gold Coast Councils.




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