Attachment 3 - Revised Engineering Report (rec. 7.04.2025) MCU24-0165 & OPW24-0222

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5.6.1.7 Stabilise Disturbed Areas
Provide temporary stabilisation of disturbed soils whenever active construction is not occurring on a
portion of the site. Provide permanent stabilisation during finish grade and landscape the site.
5.6.1.8 Protect Slopes and Channels
Safely convey runoff from the top of the slope and stabilise temporary and permanent channel crossings
as quickly as possible and ensure that increases in runoff velocity caused by the project do not erode
the channel.
5.6.1.9 Diversions of Upslope Runoff
Upslope runoff should be diverted away from areas of exposed soil to prevent the contamination of
clean runoff. This may be achieved by installing tightly abutting sandbags, creating a 'sandbag
perimeter bank' to divert flow.
5.6.1.10 Sediment Fences and Inlet Protection
Delineate site perimeter to prevent disturbing areas outside the project limits. Sediment fences should
be installed around the perimeter of works to ensure contaminated runoff is filtered and sediment is
trapped before leaving the site. Sandbags or geofabric should also be placed around/over existing
stormwater inlets/grates throughout the site to filter any contaminated runoff before entering the existing
piped stormwater network.
5.6.1.11 Retain Sediment
Retain sediment-laden waters from disturbed, active areas within the site.
5.6.1.12 Stabilised Vehicle Entry/Exit Point
A stabilised entry/exit point should be constructed to minimise the transport of sediment off-site. All
vehicles entering and leaving the site must use this designated entry/exit point.
5.6.1.13 Stockpiles
Stockpile locations should be identified before the commencement of works. Ideally, they should be
located in a flat area at least 15m from any water body or stormwater inlet. Sediment fences should be
installed downslope of all erodible stockpiles, and upslope protection measures should be used (i.e.
sandbags or sediment fence) to divert runoff in the event of rain. At the end of each working day,
stockpiles should be covered with geofabric if rain or high winds are forecast.
5.6.1.14 Street Sweeping
Ensure that local roads are swept as required. This will minimise the potential for sediment tracked onto
the road to be washed into the stormwater system. If there is a large quantity of sediment being tracked
onto the surrounding streets, the stabilised entry/exit point may need to be raked or reinforced with rock
treatment to provide more effective sediment removal for vehicles.
5.6.1.15 Erosion Control Matting and Permanent Stabilisation
Exposed areas onsite should be permanently stabilised (i.e. with turf) as the construction works
progress. Erosion control matting or mulching should be used as a temporary measure to stabilise
exposed areas before permanent stabilisation can be undertaken.
5.6.1.16 Monitoring
Monitoring and recording of the performance of the drainage control devices are to be undertaken in
accordance with local government requirements. It is further recommended that the proposed
construction works be undertaken during periods of dry weather to reduce the potential for sediment to
be transported off-site during construction.
5.6.2 Operational Phase
The State Planning Policy states that stormwater management design objectives do not apply for
developments smaller than 2500m2, with the site being smaller than this size.




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