Geosynthetics in sediment control and retention

Traditional sediment control systems are stmctures composed of permeable material and are placed so as to intercept sheet flow and low-level channel flow from denuded areas, and provide these functions. Traditional measmes are made of straw, gravel or crushed stone, and brush. Often, however, these traditional systems have not been sufficiently effective as a result of improper placement, poor installation, or inadequate stmctural and filtration properties of the materials used. 

There are generally two applications of SRDs sheet and concentrated flows. Although the same device may be used in either application, use in concentrated flows requires significantly greater structural support and anchorage of the device. 

In general, the benefits of geosynthetic sediment control systems over traditional stmctures such as rock checks and sediment traps include the minimal labor required to install them, the low cost, their high efficiency in removing sediment, their durability, and sometimes their reusabUity. The performance of sediment control systems typically depends on the proper selection and deployment of SRDs. SRDs such as silt fences typically cause the following to happen  

To perform satisfactorily as an SRD, the geotextile component must have properly sized openings, which initiate the formation of a soil filter. Also, the strength and storage capacity of the SRD must be adequate to contain the volume of water and sediment anticipated during a major storm. Hydraulic loading during a storm event is commonly 

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