Performance of geotextile silt fences in large flume tests

This paper presents the results of large-scale flume tests to assess the performance of different types of nonwoven geotextile in silt fences. Four types of geotextile and three types of soil were used in the tests, under varying values of runoff discharges. The flow rate passing through the geotextile and the upstream slurry level rising with time were measured, as well as the slurry concentration, the sizes of the soil particles that piped through the geotextile, and the permittivity of the geotextiles after the tests. The results showed the great effects of the geotextile on sediment retention and slurry concentration reduction. A greater than expected geotextile retention capacity was observed. The results also suggest that a lighter and cheaper nonwoven geotextile may be used in a silt fence if the other requirements for relevant material properties for this type of application are satisfied.