Type 3 Silt Barrier Construction
Heavy Duty Silt Barrier Construction for Rigorous Conditions
Question: Hi. I would like to more about a type 3 silt barrier construction. I need to know if there is a bottom chain, how deep the barrier can reach, and what type of fabric is used.
Answer: The typical Type 3 Silt Barrier may include a couple of different styles, but it will most usually feature a PVC fabric, marine grade flotation device, section connectors, extending skirt, and a lower heavy-duty ballast chain. The depth of your skirt varies depending on your specific location, but can include depths anywhere from three to one hundred feet (3' - 100').
Detailed Type 3 Silt Barrier Construction
The silt barrier design will feature the standard construction of an upper flotation device, skirt, lower ballast chain, and aluminum or steel section connectors. Detailed information on these barriers are as follows:
PVC Fabric: The silt barrier is typically constructed from a PVC impermeable fabric. If you are dealing with an extended depth or a barrier with increased water flows, there is also a permeable fabric model available. This model uses the same PVC fabric but adds geotextile filter panels to help filter sediment while allowing water to flow through the skirt.
Flotation Device: The flotation device on this barrier is sewn into the upper portion of the barrier to help contain sediment on the surface. These marine grade flotations are typically 6" but will increase with size as the depth of your skirt increases. This is designed to keep a balance between the top flotation and bottom skirt.
Bottom Chain Ballast: The bottom of your barrier will typically contain a ballast chain that helps to keep the skirt vertical while under the water. The barrier might also contain tension cables to help stabilize the unit.
Standard Depths and Lengths: The length and depth of your silt barrier varies depending on your specific site requirements. Barriers come in specific lengths of either 50 or 100 feet.
The depth of your barrier will change depending on specific site requirements. It is typically advised that the depth of your barrier should allow the curtain to sit approximately one foot from the bottom of your water floor. Depths can range anywhere from 3 to 100 feet.