Other Change Decision Notice - Council Meeting Decision 132005 638 04 (As Published)

STORMWATER MANAGEMENT PLAN

Client: Noosa Shire Council Location: Doonan

5.3 Proposed Stormwater Treatment Train

Stormwater runoff from the proposed development will be treated by two (2) bioretention basins prior to
discharging into the receiving environment. The proposed Bioretention Basin A will treat Sub-catchment A,
and Bioretention Basin B will treat Sub-catchment B. Table 5-3 details the associated bioretention basin
parameters used for the proposed treatment train.

Table 5-3 MUSIC Details for the Proposed Treatment Train

 

 

ee ee ree er ved tor ed er la
Pret 2 " fen) bry
ae p ‘
aie i] aay
A 122 122
o7 03
80 80

 

 

 

Refer to the engineering plans in Appendix A for further details.

5.4 MUSIC Modelling Results

MUSIC modelling of the proposed catchments was performed to ensure the nominated treatment strategy
achieves the required pollutant reduction objectives listed in Table 5-1. The target reductions in stormwater
pollutants are based on a comparison of an unmitigated scenario, having no treatment on site, and the
mitigated scenario, which has stormwater treatment measures incorporated onto the site.

As per the SPP (2017), MUSIC modelling is performed to demonstrate the environmental values of receiving
waters are not negatively impacted through the release of nutrients and sediments into waterways. Table
5-4 provides the modelling results for the proposed development being treated by the proposed bioretention
basins. Table 5-4 provides MUSIC modelling results for the overall catchment and considers all sub-
catchments in Table 5-2 and the overall proposed treatment train.

Table 5-4 MUSIC Model Results for the Overall Treatment Train

 

 

 

 

Unmitigated Mitigated toe Toads) ts Tat Ly
en A = pT
(ean) ren Pete ts en eat)
TSS 9590 1310 B11 30 Y
™. 16.7 4.39 73. 60 Y
1™N 72.6 37.2 48.8 45 Y
GP 666 0 100 30 Y

 

 

 

 

 

 

 

The MUSIC modelling results in Table 5-4 demonstrate that the stormwater management strategy proposed
for the development site meets or exceeds the target reduction rates for major pollutants required by the
NSC and the SPP (2017).

 

9 Project No: 244035

@] covey M25-0042 Rpt Issue A

Document Set ID: 24377726 Page 61 of 72

Version: 13, Version Date: 23/12/2025