1909-13367 SRA referral response approved docs

5   CO N CLU S IO N


This SWMR, with the preliminary engineering drawings, outline how stormwater run-off from the site
will be managed in order to not adversely impact the receiving environment.
The proposed relocatable home park involves the construction of 245 relocatable dwellings with a
shared clubhouse area on two currently undeveloped blocks.

The lawful points of discharge for the site have been determined to be the north, north east and south
east sides of the properties within the Cooroy golf course as detailed in Appendix AC. four bioretention
basins (One for each sub-catchment shall be constructed to mitigate developed flows to match or
reduce peak flows compared to the existing. The proposed OSD was modelled using the hydraulic
modelling program XPSTORM and has been shown to reduce peak flows for all design events ranging
from 63.2% to 1% AEP. Bioretention basin four has not been modelled for OSD purposes and is
considered to be free draining.
The proposed development triggers the requirement for stormwater quality from NSC and QLD’s state
planning policy Appendix 2. Water quality modelling was completed using MUSIC. The proposed water
quality treatment train consists of four bioretention basins (one for each catchment). The proposed
treatment train has been shown to meet the reduction targets outlined by NSC and the state planning
policy.

By implementing the proposed stormwater management system, and providing adequate maintenance,
the downstream environment and neighbouring properties will not experience any adverse deterioration
of water quality as a result of the proposed development.




                                     Stormwater Management Report                                    18
S19-007                                122 & 144 Myall St, Cooroy