The EPA Clean Water Act (1998), National Pollution Discharge Elimination System (NPDES) Phase II focuses on reducing sediment migration from construction sites that are one acre or larger.  By planning ahead and selecting the appropriate BMP’s (Best Management Practices) you can avoid fines and construction delays. Clearing, grading and other construction activities remove the vegetation and compact the soil increasing both run-off and erosion. Reduce sediment migration from your site by limiting the level of soil erosion occurring on your site. Vegetation provides cover for the soil, reduces the detachment of soil particles, and improves infiltration rates reducing the amount of water that leaves your site.  Consider minimizing soil exposure by retaining natural vegetation, adopting phased construction, and using a temporary cover.

IWT distributes a wide selection of BMP solutions such as erosion control blankets, turbidity barrier and silt fences to help our customers comply with these regulations. In selecting a BMP product one must consider the type of control that is needed and along with site conditions. The most common reason erosion and sediment control devices are ineffective is because the wrong product is selected for the application. For example silt fence is not intended to serve as an erosion control device and therefore should not be installed across a slope but rather relatively low areas suitable for ponding water and depositing sediment. The three categories of BMP products are erosion control, sediment control, and run-off control.

Erosion Control Blankets  (ECB) are used in applications where natural vegetation alone will provide sufficient permanent erosion protection. Erosion control blankets are used to temporary stabilize and protect disturbed soil from raindrop impact and surface erosion, increase filtration, decrease soil compaction and crusting, and to conserve soil moisture. These blankets are typically machine produced mats made of biodegradable mulch such as excelsior, straw, coconut fibers or a combination thereof evenly distributed on or between photodegradable polypropylene or biodegradable natural fiber netting. Some things to consider are longevity and required performance properties to control erosion and assist in the establishment of vegetation under the immediate site conditions.

Coir Mats are manufactured from pure coir fiber, the husk of a coconut and then woven into blankets with specific weight, strength and open area.  Coir fiber has one of the highest durability and tensile strength among all natural fibers. High tensile strength and durability makes it suitable for the most severe erosion control problems such as steep slopes, high velocity flow channels as well as the stabilization of stream banks and shorelines. The high flexibility of the woven coir mat allows it to easily conform to the contour of the soil and to bond tightly. Its woven feature allows planting directly into the soil through the blanket without cutting the blanket. Coir mat has the natural ability to absorb and retain water creating an ideal microclimate for the growth of vegetation. The extended longevity of coir mats allow for full vegetation establishment. After years of effective erosion control and vegetation anchoring, the coir mat biodegrades returning nutrients back into the soil. Available in 400, 700, and 900-gram weights.
 
 

Turf Reinforcement Mat (TRM) is a long term non-degradable composed of UV stabilized, non-degradable synthetic fibers, filaments, and mesh netting processed into a three dimensional reinforcement matrices. These mats are designed for permanent and critical hydraulic applications where design discharges exert velocities and sheer stress exceed the limits of mature natural vegetation. TRM's provide sufficient thickness, strength, and void space to permit soil filling and or the retention and development of vegetation within the matrix.  Our TRM’s are available in 8, 10 or 12 ounces per square yard.

There are many different ECB’s and TRM’S out on the market today. Some things you should consider when selecting a product are:

Flow velocity Longevity Material Performance Application Site conditions

Sedimentation is the deposition of soil particles that have been transported by water or wind.  The amount of sediment produced during construction is directly proportional to the degree and effectiveness of erosion control practices implemented. The quantity and size of the particles transported increases with the velocity of the runoff. 
Sediment Barriers are BMPs that are intended to separate sediment from sheet flow runoff. They function by reducing runoff velocities so that sediment cannot be transported and by ponding sediment-laden runoff long enough for the soil particles to settle out of suspension. Sediment barriers are only intended for areas experiencing sheet flow and they must be installed in areas that can pond water and accumulate sediment and, most importantly, the must be accessible for cleanout. Sediment control devices require frequent inspection and maintenance.  Sediment barriers are the most common type of practices used on construction sites.
 
 

If installed correctly silt fence is one of the most effective and economical sediment barriers. Silt fence is manufactured from geotextile filter fabric that allows water to pass through the fabric, while trapping soil particles long enough for them to settle. IWT sells a variety of silt fences to suit state and local contract specifications. Please give us a call or fax your specifications. We welcome the opportunity to provide quick turnaround at competitive pricing.

• Contractors Grade Silt Fence
• Mesh Backed Reinforced Silt Fence 
• Drawstring Silt Fence
• D.O.T. Silt Fence 
• Super Silt Fence Kits
• Pocketed Silt Fence 

Straw and Excelsior logs and wattles, when properly installed, reduce the rate of water flow by absorbing water and creating a barrier allowing sediment to settle and water to pass through. On steep slopes, wattles used in conjunction with a properly designed and installed erosion blanket results in an extremely effective BMP. They are an economical choice for stopping sediment saving time and money in pollution penalties.

Applications

• Slope Protection and Stabilization
• Storm Drain Protection
• Channel/Median 
• Drop inlet 
• Shoreline and Stream Channel Protection and stabilization
• Check Dam
• Stream, pond or riverbank protection. 

Designed to be used as a sediment filter barrier on slopes to reduce surface sheet erosion and capture sediment.

Designed to be used as sediment filter barriers where straw or hay bales have been used. For example in roadside ditches, medians, swales and around drop water inlets.

Natural coconut fiber logs used for shoreline and stream channel applications. They protect the soil from run-off by collecting sediments. Those sediments in turn nourish the seedling/ or cuttings that may have been planted during installation. Plants develop their root structure in the shoreline sediment. As the log slowly biodegrades the roots retain the soil in place allowing Mother Nature’s erosion control methods to work. 
 

Disclaimer: These guidelines are for informational purposes only and are intended as illustration or general information only and are not intended as a guarantee or warranty. IWT assumes no responsibilities in connection with the use of this information.