20517 App J.pdf [As Published] · 132007.1259

Concept Stormwater
Essence of Peregian

Management Plan

"i

 

Table 4.10: MUSIC Modelling Results for Various Scenarios

 

 

 

Model No. | Description TSS (kg/yr) | TP (kg/yr) | TN (kg/yr)
1. Existing Site plus External Catchment 2170 49 28.7
2, Developed Site — (Without Mitigation) 2640 5.5 27.8

 

45%

 

WQOs (Percentage Reduction)

 

 

80% 60%

 

     

 

 

 

 

3. Developed Site plus External Catchment -
(Without Mitigation) 3530 8.1 43.0
Mitigated Site and External Catchment 1170 3.4 28.2

 

 

 

 

 

Load Retention Achieved as % of
Developed Site Load.

 

89% 85%

 

 

53%

 

 

These results show the load retention achieved for the site and external catchments exceed that which is required
for the site only catchment. Proposed mitigation measures are therefore effective in reducing pollutant loads below
the WQOs. Pollutant loads from the mitigated site and external catchment (Model No. 5) are also significantly lower
than pollutant loads from the existing site and external catchment (Model No. 1) for TSS and TP and slightly lower

for TN.

Treatment of stormwater runoff from external site areas including the Peregian Beach Hotel site (including car
parking) and David Low Way adjacent to the site is not required by Council but has been included. The opportunity
to treat stormwater runoff from these areas has been taken and will benefit the water quality of downstream systems.
Significant achievements have been demonstrated for improvements to water quality runoff compared to existing

values.

 

BO07047-01A.doc

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