Appendix 4- SWMP

                                                                                                            ingeniir

For lots with clayey soils, the entry/exit point shall incorporate a geofabric overlaid with 40-75mm diameter
rock laid at least 150mm thick or shaker grid with access to remove accumulated sediments underneath.

Any rock-pads used for construction entry or exits points that are subject to pedestrian movements are to be
covered with an additional layer of 25-50mm diameter gravel within the verge to make it safe for pedestrians.
The formalised access point shall include a bund to direct upslope run-off to a sediment trap within the lot
and be maintained to prevent clogging of the surface with sediment that has been deposited.

5.1.5     Stormwater inlet protection

For lots which the proposed development includes the installation of internal stormwater inlet pit(s), the
pit(s) and associated piped drainage shall be established as early as possible within the works program to
formalise the site drainage.

Internal and external stormwater pits (within 40m of the site) shall be protected to prevent entry of coarse
sediment into the pit by covering the grated inlet with a filter cloth and surrounding the pit with a sediment
collection pit; combined with the use of coir logs or similar for kerb inlets. The pit(s) should be maintained in
good working order.

5.1.6     Coarse Sediment Barriers

Sediment devices are to consist of a sediment fence for the entire downstream perimeter of the works as a
minimum. Sediment fences should incorporate the barrier fabric being buried 200mm minimum into the
ground and projecting 450mm above the ground; with supporting posts at 2m centres and upslope returns at
the end of the fence typical.

For smaller sites, alternative coarse sediment barriers such as mulch or rock berms, sediment socks, fibre
rolls, or low sediment fences can be considered.



5.2     Operational Phase

The site has a lot area of 607m2 and as such does not trigger local or state requirements for operational
treatment objectives for stormwater quality.

Noosa City Council (SC6.6.2) requires a minimum of 3,000kL per dwelling for retention and re-use which will
be provided in conjunction with underground rainwater detention tank. It is proposed that a 7,500L
underground tank be provided for each unit with 3,300L retention and 4,200L detention.

In accordance with the QDC MP4.3 – Supplementary Water Sources for buildings, and the applicable
performance requirements being P11 – P17, the rainwater tanks will be used for external purposes only such
as landscape drip irrigation, pool top up and hardstand wash down/communal uses.

A water balance assessment has been undertaken to determine an appropriate retention volume, using
rainfall records from Caloundra for a 10 year and 1 year period (Refer Appendix 2 | Water Balance




                                               Ingeniir Pty Ltd | 245001-SMP-01
                 ABN: 99 642 485 363 | PO Box 988 Maroochydore QLD 4558 | [email protected] | 0404157187
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