Response to Information Request - Received on 19/04/2012 · OPW11/0335

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1.0         INTRODUCTION


Simmonds and Bristow have been commissioned by Contrast Constructions and the Scanlon
Property Group Pty Ltd to develop a Stormwater Management Plan (SWMP)and Sediment &
Erosion Control Plan (SECP)for their re-development of the Peregian Caravan Park as the
Essence of Peregian.


The plans describe two development phases; the construction                                        phase when building activity
disturbs the ground surface, which is described by the SECP, and the maintenance phase when
the development is fully built and                        operational is described by the SWMP.                      In addition, the
development will be constructed in three construction stages, with the stormwater infrastructure
being installed in two stages. A portion installed at ’Stage l’ to reflect the reduced development
installed at that stage, with the remainder of the stormwater management infrastructure installed
during stage 2 construction (for stages 2 and 3).

The intent of the plans is to protect the environmental values of receiving waters by minimising
the hydraulic disturbance and the load of contaminants in run-off from the development site.


The SECP develops an erosion hazard and risk assessment based on the soil and topography
of the development site.    This plan identifies the environmental values of the receiving water
body, and any potential consequences~that erosion of the development site might have on the
receiving water body. The SECP tncludes irlformation on how to manage the erosion and off-
site export of soil from the            deveIOPtnent\site,            I
                                                and a statement of the personnel responsible for
establishing and maintaining all erosion ahd sediment control measures.

The SWMP describes a treatment                             train,deSign to manage stormwater from the site, which
includes overland flow               across        the site from           upslope     sources.       The SWMP is based                  on

assessments and MUSIC computer modelling of likely changes to annual stormwater sediment
and nutrient loads from the proposed                           development. The plan also provides information on
managing the stormwater treatment train, and a statement of the personnel responsible for this
management.

The plans are prepared in accordance with the Queensland Best Practice Environmental
Management Guidelines 2009. References were also made to other guidelines:

           .  Introductory Erosion and Sediment Control Guidelines for Queensland Councils;
           .  IECA Best Practice Sediment and Erosion Control;
           .  Erosion & Sediment Control: A decade of lessons learnt; and
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              Controlling stormwater pollution on your building site.

This report directly follows from the conceptual SWMP and SECP report (J-0906-226: Essence
of Peregian: Stormwater Management Plan; Sediment and Erosion Control Pian). The
conceptual SWP was modified by removing some, and modifying others, of the process units
from the stormwater treatment train as follows:


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              Converting swales to hydraulic conduits and changing roof areas;
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              Vegetation in the bio-retention trenches changed from wetland plants to grass;
           .  Consolidation of Northern and Mid section bio-retention trenches
           .  Removal of the constructed wetlands.


The outcome was that suitable water quality could still be achieved with the modified treatment
system.




@2012 Simmonds & Bristow Pty Ltd                              Contrast Constructions                          J-1005-310   -
                                                                                                                               22 March 2012
1:ICLlENTFILESIContrast Constructionsl11 08.155c   -
                                                       Essence of Peregian SCEP Stage 1 Updatel09_Output Documentsl11 08-155C SWMP
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SCEMP_Scanlon Property Group_V4 O_ta_120321.doc                                                                                  Page 1 of 24