Technical & Educational Deep-Dive

For those who want the full picture — project managers, engineers, compliance officers — here’s how a silt curtain actually works in the field, from delivery to redeployment.

How Silt Curtains Are Supplied

Every project starts with delivery. Our curtains arrive furled and palletised, so crews don’t wrestle with loose fabric on the dock. Each pallet contains up to 100 metres of connected curtain, numbered and labelled so you always know which section comes next.

On larger jobs, multiple pallets are staged in sequence. If time is critical, we can even supply sections pre-connected, allowing crews to launch and tow them directly into position. This level of organisation reduces deck time and prevents costly mistakes during deployment.

Finding the Right Depth

Depth isn’t just a number — it’s the balance between control and performance. A curtain that’s too shallow lets fines escape, while one that drags the seabed risks flaring, erosion, and plume release.

That’s why we recommend leaving 0.3–0.5 metres of clearance above the seabed at low tide. This gap relieves hydraulic pressure and allows particles to settle naturally.

Think of the curtain as a brake on water flow, not a wall. It slows the current long enough for suspended sediment to drop out, protecting the waterway without choking it.

What Determines Effectiveness

The effectiveness of a silt curtain comes down to how well it’s matched to the site:

• Sediment type & load – Fine silts behave differently from coarse sands or tailings.
• Curtain design – Skirt depth, fabric type, float size, and ballast ratio must all suit conditions.
• Mooring layout – Anchors, spacing, and orientation control stability and flare.
• Hydrodynamics – Currents, tides, wind, wave climate, and vessel traffic constantly test the system.

A silt curtain doesn’t “block” water. It manages flow. When correctly designed and anchored, it creates a controlled zone where turbidity can settle — reducing environmental risk and keeping regulators satisfied.

Why Installation Defines Success

The strongest curtain can still fail if deployed incorrectly. That’s why installation is where projects are won or lost.

• Prepare the site first – Anchors and mooring lines must be installed in advance.
• Tow steadily – Curtains are moved into place while still furled, at a safe speed (≤3 knots).
• Check for twists – Before unfurling, ensure the skirt is clear and aligned.
• Release ties cleanly – Allow the skirt to drop vertically without snagging or tangling.
• Inspect final layout – Confirm anchor geometry, ballast alignment, and clearance from the seabed.

Done right, installation transforms a packaged product into a reliable line of defence against turbidity. Done poorly, it risks early failure, plume escape, and even stop-work orders.

When It’s Time to Retrieve the Curtain

Project finished? Curtain needs servicing? Retrieval should be as smooth as deployment.

• Disconnect anchors and moorings in sequence.
• Furl the skirt securely against the floats.
• Tow sections back at controlled speed to the recovery point.
• Repack on pallets or reels for cleaning.

Handled properly, removal doesn’t stir up sediment or damage the curtain — it’s simply the closing stage of the project.

Extending Curtain Life Through Reuse

A well-made silt curtain isn’t a one-off expense — it’s a reusable asset. After retrieval:

• Wash down – High-pressure cleaning removes silt and biofouling.
• Dry fully – Prevents mould, odours, and fabric breakdown.
• Inspect carefully – Check seams, floats, ballast chains, and connectors.
• Service if needed – Replace worn components.
• Repack and store – Palletise for easy redeployment.

With the right maintenance, a curtain can be redeployed across multiple jobs, turning an environmental requirement into a cost-saving investment.