Eliminating or preventing the risk in the first place can save time and money spent on managing the issue afterwards, and protect a good business reputation. This section provides information on environmental management plans and applying effective risk management measures.
Applying effective controls
It is important when selecting controls to consider how they will be used and what they are capable of achieving. For example, some control measures can be used in water ways and others cannot, some can only deal with coarse sediment, others fine sediment. The following are measures that should be prioritised:
Controls selected need to be:
- fit for purpose
- installed correctly
- maintained correctly.
The priority should be:
- preventing erosion (soil conservation protections and water diversion)
- minimising erosion (water management, wind reduction)
- managing sediment (capture, filtration).
Multiple controls (treatment trains) should be used where possible, especially for water erosion.
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Figure 5: Sediment capture by silt fence
(Source: Fulton Hogan)
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Erosion management
Managing erosion risk can help to prevent the generation of dust or sediment. Measures can include:
Note: Further fact sheets are expected to be developed on these elements soon.
Table 3 – Erosion management controls
| General erosion control category |
Specific measures |
Wind erosion |
Water erosion |
| Soil conservation |
Do not strip land unnecessarily (but when necessary avoid sensitive areas). |
✔ |
✔ |
| Maintain existing vegetative cover where possible. |
✔ |
✔ |
| Shelter belts or wind fences help slow wind. |
✔ |
|
| Manage off-site flows |
Direct water around or away from exposed areas, stockpiles, embankments or nearby sensitive areas.
Downslope water diversions |
Constructed temporary water diversion channel during works on Eastlink to divert water away from construction site and avoid erosion
(Source: Peter Higgins - State Plant Hire & Statewide River and Stream Management)
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✔ |
| Soil stabilisation |
Protect slopes and embankments.
Use matting and co-polymers.
Revegetate or re-establish grass over soil.
Hydro-seeding. |
✔ |
✔ |
| Prevent erosion of bulk materials |
Where possible, consider housing stockpiles in bays. |
✔ |
✔ |
| Prevent wind-borne dust emissions by using tarps or wetting stockpiles down (apply gentle sprays or sprinklers to prevent water erosion). |
✔ |
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| Limit machinery handling of dry dusty soil materials (especially in windy conditions). |
✔ |
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| Prevent water erosion by diverting surface runoff from other areas away from stockpiles (drainage). |
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✔ |
| Slow-wind or water flow rates |
rock armouring to slow water
baffling systems (see Fig 7)
erosion matting
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Rock Log, drainage protection, Eastlink
(Source: Ken Fraser – Statewide River and Stream Management)
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✔ |
| Wind fences and shelter belts can reduce the speed and power of wind across disturbed soil. |
✔ |
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| Minimise erosion potential from unsealed roads or thoroughfares |
Engineer and maintain roads to minimise erosion potential including appropriate material selection, grading, roadside drainage systems with integrated control systems.
Limit vehicle movements on unsealed roads or thoroughfares to minimise road or soil surface churn and structural degradation which can increase erosion potential.
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✔ |
✔ |
| Suppress wind-borne dust emissions from unsealed roads by using water carts or polymer sprays. |
✔ |
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Sediment management
Where erosion is unavoidable some sediment will be expected to be shifted through runoff. Below are some common sediment controls.
Table 4 – Sedimentation management measures
| General sedimentation control category |
Specific measures |
| Perimeter structures to capture and manage sediment |
- silt fences/barriers
- check dams
- coir logs
- earth contour banks
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Mullum Mullum Creek near Ringwood bypass construction during Eastlink project. Good example of jute mat stabilisation for erosion control and sediment fence to capture sediment getting into creek during construction phase
(Source: Peter Higgins - State Plant Hire & Statewide River and Stream Management)
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| Water treatment, filtration or retention |
- grass filter strips
- bio-retention swales
- sedimentation basins
- infiltration systems/porous pavement
- flocculation/precipitation agents
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| Install in-stream measures |
- silt curtains
- silt filters
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Silt filter bale collecting ash after Black Saturday bushfires in Steele’s Creek
(Source: Ken Fraser – Statewide River and Stream Management 2009)
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| Protect the existing drainage system |
- coir log filters
- culvert gravel filters/rock logs
- engineered drainage systems with flow slowing or load management measures
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| Reduce tracking of sediment by vehicles |
- establish stabilised points of site entry and exit
- limit vehicle movements on wet soil
- tyre vibration grates
- tyre washes
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Truck passing over tyre vibration grate
(Source: Fulton Hogan)
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Administrative controls
Administrative controls include plans and procedures combined with provision of related training to staff and contractors, for example:
- train staff on how to implement plans and procedures and apply effective control measures
- ensure staff and contractors follow established procedures for installing and maintaining control measures, and keep records.
If you or your staff seek further, more detailed training, consider courses provided by registered training organisations.
Environmental management plans
An environmental management plan (EMP) can help document and guide the prevention or minimisation of environmental risks (like erosion) and are useful tools for communicating to employees and contractors. An EMP can have increased value for business operations or activities with greater risk levels and can include elements like:
- Prior planning, risk assessment and design work, consider:
- Activity risk factors (what activities are being undertaken on site)
- Site risk factors (both within and beyond the site)
- Environmental objectives
- Selecting appropriate and effective erosion and sediment control measures
- Installation, inspection, maintenance and monitoring work
- Ensure controls are correctly installed
- Regular checking and maintenance of controls
- How effective are they on an ongoing basis?
- How suitable are they when activities or site conditions change?
- Monitoring of water quality to assess control effectiveness
- Respond where measures are broken or ineffective
Note: Although budgets are normally considered separately to EMPs, consider the costs for erosion and sediment control when establishing business budgets or tenders.
The following tool can assist with this:
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