TURBIDTY BARRIERS are a BMP designed to restrict the flow of sediment-laden stormwater runoff from a construction site, to keep it contained in a limited area, and allow the sediment to settle out before being carried into adjacent or joining watercourses. TOUGH GUY® Turbidity Barriers are manufactured by AER-FLO, Inc., the world’s largest producer of these critical devices.
FLOATING TURBIDITY BARRIERS, also called silt containment curtain consist of a top flotation boom, an impervious fabric curtain extending downward under water, and a heavy galvanized steel chain sealed into a hem along the entire bottom of the curtain to provide ballast to keep the curtain vertical in the water. End hems are sealed around a rope and grommeted to allow attachment to each other with rope or bolt/nuts/washers. Color is Tough Guy Yellow.
There are three TYPES of FLOATING TURBIDTY BARRIERS:
Type 1 DOT
Type 1.DOT is the most frequently specified barrier in the TOUGH GUY® line. It is recommended for construction sites located in protected areas that are exposed only to light winds and to current velocities of less than one foot per second. This type of site may include ponds, shallow lakes, small streams and marshes.
Anchorage consisting of stakes or concrete blocks may be required to maintain the barrier in its required position. Barrier sections are connected by rope lacing or nylon ties which must be furnished by others.
Type 2 DOT
Type 2.DOT is the work horse of the TOUGH GUY® line. It has a top load cable and special stress plates for reinforcing the corners and is designed to handle more severe conditions. It is recommended for lakes, streams, intercoastal and tidal areas where current velocities up to five feet per second are expected.
The anchorage and installation must be designed to meet the site conditions. Contact Aer-Flo Canvas Products, Inc. or a qualified engineer for assistance when extraordinary site conditions are encountered. Barrier sections are connected by rope lacing or nylon ties which must be furnished by others.
Type 3 DOT
Type 3.DOT is a special adaption of the Type 2 barrier. Approximately 20 % of the area of the barrier skirt fabric is replaced with a polypropylene filter fabric conforming to some State DOT specifications. The filter fabric is inserted to reduce the pressure on the curtain while retaining silt. In actual practice, a filter fabric which is woven tightly enough to retain silt will not significantly reduce pressure on the curtain. Conversely, if the filter fabric is woven loose enough to reduce the pressure on the curtain, it will not be able to retain most silt and sediment particles. In addition, the filter fabric cannot be heatsealed, and must be sewn into the curtain, resulting in a reduction in curtain strength and longevity.
Types1.DOT, 2.DOT, and 3.DOT MEET OR EXCEED ALL KNOWN FEDERAL AND STATE GOVERNMENTAL SPECIFICATIONS, INCLUDING NPDES PHASE II REQUIREMENTS.