Judgment - Stockwell v Noosa Council - PEC Appeal 1998 of 2024 - 26.06.25 · MCU22/0094

The Stormwater Management Plan outlines the site in two sections, the operational phase and the
construction phase. The operational phase addresses treatment of contaminated runoff from the
developed site by natural methods before discharging into receiving waters whilst the construction
phase of the Stormwater Management Plan addresses erosion and sediment control to prevent
contamination of water sources by stormwater runoff during construction of the site.

6.4       Operational Phase
6.4.1     Proposed Site Drainage

Stormwater runoff from the proposed development will be collected and conveyed in a new stormwater
pit and pipe network to the Noosa Civic stormwater network.

Stormwater runoff from the new roof, carpark and landscaped areas will be directed to one of two
bioretention basins, or an OceanProtect Jellyfish device for stormwater quality treatment. High flow
bypasses will be constructed around the bioretention basins for flows exceeding the treatment flows.

Approximately 330m2 of the access driveway, pavement and landscaped areas, to the south of the
bioretention basin at the entry and the landscape buffer area, will bypass the bioretention basins and
the OceanProtect Jellyfish device to allow the driveways to join neatly into the existing external road. The
treated areas will be over treated so the overall net water quality objectives are achieved for the
development.

Stormwater treatment will be implemented to remove sediments, nutrients, gross pollutants and
hydrocarbons in accordance with the requirements of Noosa Council and the State Planning Policy.

This development sits within a lot that has been allowed for in previous masterplan stormwater
calculations, therefore no detention is proposed for this development.

Existing stormwater pipes from both basins will outlet to external stormwater network. An upstream
stormwater inlet pipe will be constructed at the northern boundary to capture external site runoff and
bypass the 12m2 bioretention basin. This will outlet to the existing pipe, to the western boundary of the
site to provide a discharge point for the balance lot to the North.

The proposed conceptual stormwater drainage layout is depicted on MPN Plan 9307-CP.1.01, attached in
Appendix C.

6.4.2 Stormwater Quantity Management Strategy

The proposed development site will connect into the existing drainage system for Noosa Civic. The sites
minor flows will run through the existing pipe system whilst the major overflows will overland flow down
the internal driveways and into the drainage channel to the west of the site prior to discharging to the
Creek Tributary to the south of the site. The development flows will be contained within the existing
Noosa Civic masterplan drainage system.




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Inspired engineering

10 April 2025
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