Construction requires extensive earth movement, so some erosion is bound to happen. However, builders should be aware of the consequences — erosion can adversely affect the local plant, animal and aquatic life, as well as ruin the property’s soil quality. Professionals must use these 10 erosion control methods to keep their projects safe and eco-friendly.
1. Turbidity Curtains
Sediment curtains are one of the most effective erosion control methods, regardless of the construction project’s size and scope. They’re also called turbidity barriers, silt curtains and silt blooms. These barriers block sediment from getting into waterways near the worksite.
The flotation devices that stabilise turbidity curtains consist of water-resistant fabrics, so you don’t have to worry about long-term water damage. Using these curtains with automated software and video surveillance is common so site managers can monitor sediment activity around the barriers.
2. Stabilisation Walls
Stabilisation walls — also known as mechanically stabilised earth (MSE) walls — have emerged as viable replacements for traditional concrete retaining walls. MSE walls are composite structures with multiple alternating layers, including a concrete levelling pad, soil reinforcement and backfills to strengthen the wall.
The main appeal of MSE walls is their simple and fast installation since most of the wall consists of soil and other natural materials instead of only concrete. The broader range of materials also makes them more flexible, which helps them adjust to underground changes in seismic resistance.
3. French Drains
Piping is a crucial erosion control method and French drains are among the best types of piping available. They consist of corrugated or PVC pipes 250–500 millimetres wide, depending on how much water you need to drain. The pipes carry groundwater and the project’s run-off water to specified exit points, eliminating much of the water erosion.
French drains are convenient because you don’t need to bury them far below ground — 20–60 centimetres will suffice for most projects. However, you must keep the pipes sealed with strong landscaping fabric to prevent sand, clay and silt from clogging the drains and interfering with water drainage.
4. Soil Nails
Slope failures are one of the most common causes of erosion on construction sites. Soil nails are the best erosion control methods for this problem. They consist of a chain of steel bars drilled into the dirt with compressed air launchers, often attached to excavators and other construction vehicles.
The powerful launcher allows the bars to enter the earth without disturbing or loosening the soil around it, which creates a stronger nail/soil bond than traditional drilling methods. The nails are then capped at the ground’s surface, creating a barrier resembling a line of retaining walls. The barrier of soil nails prevents slope failures and keeps the worksite stable.
If your goal is to control erosion and improve soil quality simultaneously, geotextiles are your best option. Their flexible warp-knitted or open-mesh designs make them ideal additions before installing roads, pipelines, embankments and other earth-retaining infrastructure. They stabilise the structures and improve the soil’s California bearing ratio value.
The CBR value of your project’s soil depends on its density. A strong sub-base should have at least a value of 80, while lighter materials like sand and clay are in the 2–10 range. A healthy CBR value means that your worksite has stable soil and erosion is less of a threat.
6. Articulated Concrete Blocks
Articulated concrete blocks (ACBs) are a collection of individual blocks that form an erosion-resistant overlay and serve various vital purposes. They can support drainage channels, dikes, pipelines, spillways, boat ramps, coastal shorelines and many other sites prone to frequent water or soil erosion.
ACBs are also available in different shapes and thicknesses, which makes them highly versatile. You just need to connect them with a series of cables and mould them into the existing soil. However, since concrete isn’t porous, you must watch out for cracks during construction. If water gets trapped in the gaps, it could cause further damage.
7. Inflatable Dams
If you are looking for a cheap erosion control method, inflatable dams are a safe option. They’re cylindrical rubber tubes placed across waterways to raise the upstream water level and prevent sediment from getting downstream. They’re much easier to use than earthen dams, sandbags and similar labour-intensive methods.
Rubber is ideal for stopping water run-off because it conforms to the landscape and fills up every crevice. The rubber also naturally deflates as the water level rises, which prevents overflow.
8. Dust Control
Dust is one of the greatest polluters on construction sites. Workers and vehicles kick up lots of dust during the project, which worsens the air quality and gets into local waterways. Since dust is everywhere and often difficult to see, you need to implement multiple control measures. Air purifiers and scrubbers are the easiest solutions.
To keep enclosed rooms pure, you must also cover all vents and ducts with dust barriers. Silt fences, polymer additives and water mist turbines are a few other options. Water mist turbines are often used when employees operate jackhammers and other powerful tools that kick up hazardous dust.
Riprap is a popular way to protect soil from erosion in concentrated run-off areas. They consist of large stone layers that form barriers on steep slopes, often overlooking riverbeds and the shores of lakes, ponds and streams. You can also implement geotextiles into the layer of stones for extra reinforcement.
10. Site Inspections
As always, routine site inspections are crucial for reducing your construction project’s environmental impact. They can help you control much of the project’s sediment and erosion issues. Make sure you inspect the site after every rainfall and constantly communicate with your workers. Just like any other form of preventative maintenance, erosion control depends on timeliness and consistency.
Erosion Control Requires a Multifaceted Approach
Your erosion control methods should always come in groups. Using just one or two strategies might cut costs, but it also increases the risk of erosion-caused damage. Take a multifaceted approach with a handful of these methods and leave nothing to chance. Your projects will be more safe and sustainable for the surrounding community.