A silt fence is a temporary sediment barrier made of porous fabric. It’s held up by wooden stakes or metal posts driven into the ground, so it’s inexpensive and relatively easy to remove. The fabric ponds sediment-laden stormwater runoff, causing sediment to be retained by the settling processes. A single 100 ft. run of silt fence may hold 50 tons of sediment in place.
Per the Environmental Protection Agency (EPA), keeping soil on a construction site, rather than letting it be washed off into natural water bodies such as streams, rivers, ponds, lakes, wetlands and estuaries prevents the degradation of aquatic habitats and siltation of harbor channels. By not letting soil wash off onto roads, which readily transport it to storm sewers, avoids having sewers clogged with sediment. The cost of installing silt fences on a watershed’s construction sites is considerably less than the costs associated with losing aquatic species, dredging navigation channels, and cleaning sediment out of municipal storm sewers.