Managing erosion and sediment runoff is a critical part of any construction, landscaping, or revegetation project—especially when earth is disturbed or near waterways. One of the simplest and most effective ways to control sediment movement is with silt fencing. Whether you’re managing a residential site or a large-scale civil project, silt fencing can help protect nearby environments and keep your project compliant with regulations.
In this article, we’ll cover when to use silt fencing, why it’s important, and how to install it properly for maximum effectiveness.
1. What Is Silt Fencing?
Silt fencing is a temporary barrier made from woven geotextile fabric, designed to intercept and slow the flow of runoff water. It allows water to pass through while trapping sediment and debris, preventing it from leaving the site or entering sensitive areas like creeks, stormwater drains, or neighbouring properties.
Key Features:
- UV-stabilised for outdoor durability
- Permeable fabric allows water through while capturing fine sediment
- Fast to install and easy to remove
- Essential for regulatory compliance on development sites
2. When Should You Use Silt Fencing?
Silt fencing is best used as a short-term sediment control measure during earthworks, landscaping, or replanting jobs. Consider installing it when:
- You’re disturbing soil during excavation, grading, or construction
- The site is on a slope or prone to runoff during rain
- You’re working within 50 metres of a drain, watercourse, or kerb inlet
- You’re managing a project near wetlands, creeks, or bushland
3. Why Silt Fencing Matters
Uncontrolled sediment can cause a range of problems:
- Environmental damage: Sediment can smother waterways, reduce water quality, and harm aquatic ecosystems.
- Regulatory risk: Most councils and environmental authorities require sediment control measures like silt fencing on disturbed sites.
- Project delays: Failing to manage erosion and runoff properly can lead to fines, stop-work notices, or expensive site remediation.
4. How to Install Silt Fencing
Installing silt fencing correctly ensures it functions as intended. Here’s a step-by-step guide:
Step 1: Set Your Line
- Determine where water and sediment will flow and mark out your fence path accordingly—always install along the contour of the slope, not up and down.
Step 2: Dig a Trench
- Dig a trench at least 150 mm deep along the marked line to bury the base of the fence and prevent water from flowing under it.
Step 3: Drive in Posts
- Use Steel Fence Posts or hardwood stakes at 1.5–2 metre intervals along the trench.
- Ensure posts are firmly driven into the ground—at least 400 mm deep for stability.
Step 4: Attach the Fabric
- Unroll the silt fencing and attach it to each post using staples, wire ties, or fencing clips.
- Make sure the fabric extends into the trench and is buried under at least 100 mm of soil, then backfill the trench and compact it.
Step 5: Inspect and Maintain
- Check your fencing regularly—especially after heavy rain—to make sure it’s still intact and functioning properly.
- Remove collected sediment once it reaches one-third the height of the fence.
5. Complementary Products for Silt Control
To maximise erosion and sediment control, silt fencing can be used in combination with other products:
- Coir Logs – Slow water movement upslope and reduce sediment flow to the fence.
- Geotextile Filter Tubes – Ideal for directing and filtering concentrated runoff flows.
- Hessian Sandbags – Useful for emergency water diversion or stabilising high-flow zones.
Conclusion
Silt fencing is a simple, cost-effective tool for controlling sediment and complying with environmental standards on construction and revegetation sites. It’s easy to install, requires minimal maintenance, and plays a crucial role in protecting nearby ecosystems.
Whether you’re managing a small landscaping job or a major site development, Malmsbury Timbers supplies the silt fencing and accessories you need to keep your site compliant and environmentally safe. Contact us for advice or to place your order today.