Biosecurity.biz is a web service for BEG Group LLC, a manufacturer of erosion/filtration medium

Applications  

Preventing soil erosion and providing filtration is critical in protecting your property and exposed soil, whether from wind, weather, running water, and even the after-effects of forest fire. Below are some of the types of erosion/filtration capabilities of Big Switch®/Phalanx Bio Switch®  Erosion-Filter Medium.

 

Erosion/Sediment Control

Pollutant Removal

Stormwater Management

Habitat Pollinator Initiatives

Slip Repair
 


Big Switch®/Phalanx Bio Switch® Erosion-Filter Medium

Description

Big Switch® is a sturdy photodegradable polypropylene geotextile (woven) fabric (see note below) that has been engineered specifically for controlling erosion and containing and/or retaining sediment in disturbed areas. It is a mesh tube filled with biobased material that is placed perpendicular to sheet-flow runoff. Big Switch®, which is oval to round in cross section, provides a three-dimensional medium that retains sediment and other pollutants (e.g., suspended solids, tannic acid, nitrates, phosphate’s and motor oil) while allowing the cleaned water to flow through. Big Switch® can be used in place of traditional sediment and erosion control tools such as a silt fence, straw bale barrier and mulch socks.

NOTE: As of October, 2016, BEG Group offers a biodegradable cotton fabric product which is 100% biodegradable trade named Phalanx Bio Switch® 

Big Switch®/Phalanx Bio Switch®  Erosion-Filter Medium are generally placed along the perimeter of a site, or at intervals along a slope, to capture and treat storm water that runs off as sheet flow. Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium are flexible and can be filled and easily moved into position, making them especially useful on steep or rocky slopes where installation of other erosion control tools is not feasible. With Big Switch®/Phalanx Bio Switch®  Erosion-Filtration Medium there is greater surface area contact with soil than typical sediment control devices, thereby reducing the potential for runoff to create rills under the device and/or create channels carrying unfiltered sediment.

Additionally, they can be laid adjacent to each other, perpendicular to storm water flow, to reduce flow velocity and soil erosion. Big Switch®/Phalanx Bio Switch®  Erosion-Filter Medium can also be used on pavement as inlet protection for storm drains and to slow water flow in small ditches. Big Switch®/Phalanx Bio Switch®  Erosion-Filter Medium are 8, 12, 18, and 24 inches in diameter.

Big Switch®/Phalanx Bio Switch®  Erosion-Filtration Medium can be un-vegetated or vegetated. Vegetated product can be left in place to provide long-term filtration of storm water as a post-construction best management practice (BMP). The vegetation grows into the slope, further anchoring the filter. Big Switch®/Phalanx Bio Switch®  Erosion-Filtration Medium are often cut open when the project is completed, and the filter material is spread around the site as a soil amendment.

Advantages Big Switch®/Phalanx Bio Switch® has over traditional sediment control tools, such as a silt fence, and mulch are:

  • Installation does not require trenching disturbing the soil surface.
  • Medium is much more easily installed.
  • Medium can be installed where trenching is not viable.
  • Medium has a wider contact surface area.
  • Medium does not contribute additional tannic acids.
  • Medium does not need to be removed.
  • Due to the light weight of Big Switch®/Phalanx Bio Switch® vs. wood mulch you save on back strains and shipping cost.

Applicability

Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium are applicable to construction sites or other disturbed areas where storm water runoff occurs as sheet flow. Common industry practice for filter devices is that drainage areas do not exceed 0.25 acre per 100 feet of device length and flow does not exceed one cubic foot per second (see Siting and Design Considerations). Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium can be used on steeper slopes with faster flows if they are spaced more closely, stacked beside and/or on top of each other, made in larger diameters, or used in combination with other storm water Best Management Practices.

Siting and Design Considerations

Materials: Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium achieves the proper balance between sediment removal and flow-through rate by using biobased material with the proper particle size. Filter material with a high percentage of fine particles will clog and create a barrier to flow. Alternatively, filter material with particles that are too large will allow flows to pass through the barrier with little or no resistance, eliminating the velocity reduction and sediment trapping benefits of the barrier.

Design

Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium are round to oval in cross section; they are assembled by tying a knot or zip tie at one end of the mesh, filling the filter with the medium then knotting or zip tying the other end once the desired length is reached. Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium, the length of the slope, is normally used to ensure that storm water does not break through at the intersection of Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium placed end-to-end. In cases where this is not possible, the Big Switch®/Phalanx Bio Switch™ Erosion-Filtration Medium are placed end-to-end along a slope and the ends are interlocked. The diameter of Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium used will vary depending upon the steepness and length of the slope.

Installation

Once Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium is filled and put in place, it should be anchored to the slope. The preferred anchoring method is to drive stakes through the center of the tube at regular intervals; alternatively, stakes can be placed on the downstream side of the Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium. Stakes should be wooden 2” X 2“of appropriate length to provide 12” embedding in the ground + the sock diameter + 2” sticking above the sock and at 10’ spacing. The ends of the Filter should be directed up-slope to prevent storm water from running around the end of the Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium.

Limitations

Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium offers a large degree of flexibility for various applications. To ensure optimum performance, heavy vegetation should be cut down or removed, and extremely uneven surfaces should be leveled to ensure that Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium uniformly contacts the ground surface. Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium installed perpendicular to flow in areas where a large volume of storm water runoff is likely, but should not be installed perpendicular to flow in perennial waterways and large streams.

Maintenance Considerations

Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium should be inspected regularly, as well as after each rain event, to ensure that they are intact and the area behind Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium is not filled with sediment. If there is excessive ponding behind Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium or accumulated sediment reaches the top of the device, an additional Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium should be added on top or in front of the existing device in these areas, without disturbing the soil or accumulated sediment. If Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium was over topped during a storm event, the operator should consider installing additional Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium on top of the original, placing an additional device up the slope, or using an additional BMP such as hydro seeding, matting/netting or compost blankets in conjunction with the Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium.

Effectiveness

A large number of qualitative studies have reported the effectiveness of tube devices in removing settle able solids, total suspended solids and turbidity reduction from sediment laden water, (see Dr. Amanda Cox, Colorado State University, 2011). These studies have consistently shown that such tubes devices, i.e. Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium, are at least as effective as traditional erosion and sediment control BMP’s and often are more effective. Big Switch®/Phalanx Bio Switch® Erosion-Filtration Medium are often used in conjunction with hydro seeding, matting/netting, or compost blankets to form a storm water management system. Together these BMPs retain a very high volume of storm water, sediment and other pollutants.