Attachment 8 - Interim Stormwater Management Plan - TOPO · 132005.638.06

R5304: NOOSA RESOURCE RECOVERY CENTRE - STORMWATER MANAGEMENT PLAN




Figure 6 – Site Plan (Source: Covey Project No. 244035, Sheet No. C1002)



4.1.1.           SW2 HES BASIN
A concept design was undertaken for the HES basin proposed to discharge runoff to SW2. The basin was sized for a 7.83
hectare catchment, with diversion drains designed for the 1 in 10 year ARI event with additional freeboard.

A Type A basin is proposed, similar to SW5, and designed to achieve the 90 % annual runoff target. This was
demonstrated with water balance modelling in MUSIC. The Covey stormwater management plan and preliminary basins
design appears consistent with the concept design that was provided and is therefore considered appropriate for the
northern portion of the site.

For further details, refer to the concept design report included as Appendix C - Concept Design Report – HES Basin and
Drainage: Noosa Landfill – RRA (Topo R3341).

4.1.2.           LOW EROSION RISK AREAS
Per the requirements of DETSI 2025, runoff from low erosion risk areas, such as the Cleanaway Depot, Reviva Centre,
and areas surrounding the transfer station can be treated in bioretention systems designed to achieve load-based
reduction targets of 80 %, 60 % and 45 % for TSS, TP and TN respectively. MUSIC modelling will be undertaken as the
design of these areas progresses.

Typically, bioretention systems require approximately 1.5 % of the contributing catchment area to be provided as filter
media, with extended detention depths of 200 to 300 mm typically provided.

Subject to final levels, saturated zones may be required to discharge runoff from the treatment systems. All designs will
be undertaken in accordance with the IPWEAQ Water Sensitive Urban Design. Typical sections provided by IPWEAQ are
included as Figure 6 and Figure 7, for a conventional and a saturated filter media system. Refer to Appendix D for further
details.


Environment. Engineering. Education.                                                                               PAGE 12