Turbidity Curtain Along Waterway

Silt Curtains: An Overview

Due to the impact on the environment and further demands associated with pollution, silt curtains are being used in a wide variety of construction projects. Silt curtains were originally designed to contain the spread of sediment during dredging and reclamation. They are now used for dewatering, outfall containment to intake protection, stormwater management, the reduction of agricultural impact, and many other purposes.

During times when sediment control was needed for marine environments, the first approach is to identify the range and objectives that are achieved by using silt curtains also called a floating silt barrier. Some examples include stopping the spread of potential heavy metals or contaminants and reducing turbidity outside of the contaminant areas. Having the correct design, layout, and anchoring configuration is very important to ensure silt curtains achieve an effective solution. There are many factors that influence design and anchoring from current and wave height to water depth, location, conditions of the seabed, the equipment, configuration of the layout, the kind of construction work needed, the type of sediment, and environmental regulations.

As with many things, one size does not fit all. Each design has many factors that are important to a project's specific conditions and requirements.  An individual appraisal will dictate the right silt curtain for the best results. As an example, a bespoke barrier with interchangeable depths can be a flexible and potent solution to meet environmental and operational requirements such as dredging and dewatering.

Within the dredging industry, whether it's hydraulic dredging or mechanical dredging, all projects are subject to a level of particle suspension. From the construction of ports or land reclamation, all systems are used to contain particle or contaminant suspension, but silt curtains are the most economical and environmentally friendly answers. In Europe, silt curtains are used for maintenance dredging of areas that have high concentrations of pollutants including chemicals and heavy metals in marine sediments.  As European rivers are high in turbidity, containing these elements focuses more on the reduction of turbidity due to other circumstances such as bank erosion and stormwater pollution.

Workers Installing a Silt Curtain

A Type 1 Turbidity Curtain

Long-Term Sustainability and Ecosystem Protection

One of the leading benefits of collecting turbid water is to limit fine material from traveling to areas such as ecologically sensitive habitats, sea-grass meadows, corals, mangrove forests, and shellfish beds. Other sensitive areas include socio-economic benefits and water intakes used for desalination or cooling water. In Europe, another benefit is to hold back floating pollutants as oil at the top of the curtain is usually made from the same or similar material as an oil boom.

Using a secure silt curtain can protect and maintain the marine ecosystems so they will stay healthy, thriving, and undisturbed. In addition, Silt Curtains have long-term sustainable benefits, they are incredibly strong, and can be reused instead of ending up in a landfill. Sustainability is now a requirement for investment which is another important factor.