Soil erosion as the land-degrading process induced by the natural forces of water and wind and accelerated by human activity has become a worrying issue in recent decades. According to a study conducted by the World Wildlife organization, 50% of our fertile topsoil has been lost over the last 150 years. This is not troublesome information only for the environmental preservation experts; this fact should alarm economists as well.
Such immense soil loss accompanied by sediment deposition in our lakes, streams and rivers leads to adverse consequences like catastrophic slope failures that endanger human properties and infrastructure, deterioration of navigable waterways,wildlife habitat loss, and water pollution. On the economic level, soil erosion massively affects the agricultural sector by reducing soil fertility and crop yield, simultaneously increasing water usage. Construction is another industry affected negatively by soil erosion and sedimentation.
For these reasons, experts from different fields, including government agencies, civil engineers, product manufacturers and contractors, have been devising various erosion control products and practices to effectively protect the soil and hold it in place.Stabilizing ground, preventing surface runoff and keeping sediment away from waterways are the most significant tasks of soil erosion control projects. Historically, “hard armor” materials like rock riprap have been used to protect soil from erosion.
However, the quarrying, processing, hauling and placement of rock is very equipment intensive, resulting in a large carbon footprint and high installed costs. Rock is generally not considered an environmentally-friendly solution for erosion protection, so many designers and regulators today are using more green, vegetative products and practices for more sustainable job site erosion protection. This article will focus on different types of vegetative “soft armor” products and their role in soil erosion prevention. It will present their features and show how to apply the different types of soft armor products to achieve the best results in soil erosion prevention.
Different Types of Soft Armor Erosion Control Solutions
Rolled Erosion Control Products (RECPs) are a category of erosion control materials manufactured and supplied in roll form. First introduced to the market in the early 1950s in the form of natural jute fiber nettings and wood excelsior blankets, this technology has advanced dramatically through the years with more sophisticated products today able to permanently
tackle severe erosion problems and provide a lower cost, vegetative alternative to rock riprap. The Erosion Control Technology Council (ECTC) organizes
RECPs into two primary categories based on longevity (temporary or permanent) and three product types:
- Open-Weave Textiles (OWT)
- Erosion Control Blankets (ECB)
- Turf Reinforcement Mats (TRM)
For applications where natural vegetation alone will provide sufficient permanent erosion protection, a temporary rolled erosion control product may be used. Temporary erosion control products provide necessary longevity and performance properties to effectively control erosion and assist in the establishment of vegetation under the anticipated immediate site conditions.
Open Weave Textile (OWT)
One form of a temporary RECP is an open weave textile (OWT.) OWTs are a degradable product composed of processed natural or polymer yarns woven into a matrix, used to provide erosion control and facilitate vegetation establishment.
Erosion Control Blankets (ECB)
Another temporary RECP is an erosion control blanket (ECB), which is a degradable RECP composed of processed natural or polymer fibers mechanically, structurally or chemically bound together to form a continuous matrix to provide erosion control and facilitate vegetation establishment. ECBs are also available in 100% biodegradable materials or a combination of biodegradable fibers and photodegradable nettings.
- Biodegradable Erosion Control Blankets are made of organic materials like straw, wood or coconut fiber, bound together with jute or coir fiber nettings. These products are desirable for sites where the preservation of the environment is the utmost priority. Break-down time of biodegradable ECBs may range from six months to over two years.
- Photodegradable Erosion Control Blankets
This type of ECB contains netting made of synthetic materials that will degrade in sunlight over time. Based on the type of polymer and additives used, these nettings may breakdown rapidly with UV exposure (30 – 45 days), or may take up to 2 years or longer. The type of netting used should be matched with the desired functional longevity for the product on specific project sites.
According to ECTC, for applications where natural vegetation alone will not sustain expected flow conditions and/or provide sufficient long-term erosion protection, a permanent rolled erosion control product may be required. Permanent erosion control products provide the necessary performance properties to effectively control erosion and reinforce vegetation under the expected long-term site conditions.
Turf Reinforcement Mats (TRM)
A turf reinforcement mat (TRM) is a permanent RECP composed of non-degradable synthetic fibers, filaments, nets, wire mesh and/or other elements, processed into a permanent, three-dimensional matrix of sufficient thickness. TRMs, which may be supplemented with degradable components, are designed to impart immediate erosion protection, enhance vegetation establishment and provide long-term functionality by permanently reinforcing vegetation during and after maturation. TRMs typically are used in hydraulic applications, such as high flow ditches and channels, steep slopes, stream banks, and shorelines, where erosive forces may exceed the limits of natural, unreinforced vegetation or in areas where limited vegetation establishment is anticipated.
Hybrid Turf Instant Armor Mats
Though conventional TRMs provide a very high level of erosion resistance once they become fully vegetated, these products offer limited soil protection before and during the establishment period. Since vegetation can take several months to several years to fully establish, conventional TRM systems are often prone to pre-vegetated failures, especially under today’s climate-change-fueled, more frequent extreme storm events. Identifying this shortfall, GrassWorx LLC of St Louis, MO, has developed new Hybrid Turf Instant Armoring products that are forging a new class of permanent rolled erosion control products. These products, including the company’s InstaTurf ShearForce10 Instant Armor Mat and ShearForce12 Instant Armor Scour Mat, offer rock-like erosion protection from day-one of installation, to better ensure the development of a permanently reinforced, vegetative system.These revolutionary new erosion control products utilize simulated turf to protect, grow and permanently reinforce natural vegetation. InstaTurf products successfully combine the most prominent advantages of soft armor systems with the immediate protection and endurable performance of rock rip-rap. These products are much more effective for immediate, pre-vegetation erosion protection than conventional Turf Reinforcement Mats (TRMs) or High Performance Turf Reinforcement Mats (HPTRMs). While ShearForce10 Hybrid-Turf Instant Armor Mat is ideal for permanently protecting severe slopes, channels, streambanks, and shorelines, ShearForce12 Hybrid-Turf Instant Armor Scour Mat effectively protects culvert and pipe outfalls, down chutes, and the other turbulent flow areas. Both of these soft armor erosion control products have indisputable advantages over similar soft armor and competing hard armor solutions, including:
- 3 – 4 times the permissible unvegetated shear stress rating of conventional TRMs and HPTRMs, no waiting on vegetation growth to get rock-like erosion protection
- Immediate erosion protection equivalent 30-inch diameter rock riprap
- Lower installed costs than rock riprap and other hard armor. For example, ShearForce10 Hybrid-Turf Instant Armor Mat is typically 50 to 60 % cheaper than large rock riprap
- Easier long-term maintenance than riprap, just mow over with standard equipment
- Aesthetically-pleasing with a natural grass-like finish
- Require no heavy equipment for installation, reducing truck and equipment traffic into and on construction sites, resulting in a much smaller carbon footprint
- Enhance and permanently reinforce natural vegetation, which allows runoff infiltration, helps filter pollutants from runoff water and reduces thermal pollution
- Highly UV stable, weather-resistant, and easy-to-install
Indisputable Advantages of InstaTurf Soft Armor Mats
We have already mentioned some of the favorable features of InstaTurfs Instant armoring ShearForce products compared to conventional TRMs and hard armor materials. Here is a recap of why you should choose these products over hard armor solutions to protect high flow areas on project sites. Compared to hard armor erosion control solutions, Hybrid Turf Instant Armor Mats are:
The average cost of large rock rip-rap ranges from $5.00 to over $14.00 per square foot installed, depending on rock size, availability, transport distance, and other factors, while InstaTurf ShearForce10 installations typically cost$2.25 – $2.50 per square foot. The ShearForce10 is typically less expensive for contractors to buy than rock, and considerably less costly to install. The ShearForce10 requires no over-excavation and less site preparation than rock installations, reducing expensive heavy equipment time and labor. Furthermore, with just one 270 square foot roll of ShearForce10 able to protect the same size area as over 30 tons of 18-inch rock, using ShearForce10 drastically reduces large truck traffic in and out of construction sites and produces a much smaller carbon footprint.
Highly Effective Permanent Rolled Erosion Control Products
This new class of permanent rolled erosion control products offers 3 to 4 times the erosion resistance of conventional TRMs and high performance TRMs, with unvegetated permissible shear stress ratings at or exceeding 12lbs/sf. This level of immediate erosion protection is greater than that provided by 24-inch rock riprap.
Simple to Install
Hybrid Turf Instant Armor Mats are easy to install, just prepare a seedbed on the soil surface, apply seed, position mat on top and anchor in place. Proper installation procedures per application type are available here. No heavy equipment is necessary to place and anchor these products.
Hybrid Turf Instant Armor Mats work in conjunction with vegetation to function as a component in the ecosystem and facilitate water filtration and infiltration.
Hybrid Turf Instant Armor Mats utilize simulated turf to protect, establish and grow natural vegetation, giving projects a green, grassed-in look immediately upon installation.
This article provided a list of soft armor products you can use to fight the dire effects of soil erosion. In addition to a detailed description of these erosion control products, you now know where to apply them for cost-effective erosion protection. Hybrid Turf Instant Armor Mats are the pinnacle of soft armor products, offering numerous advantages over conventional ECBs, TRMs and the more expensive, less eco-friendly hard armor materials. If you want to learn more about the newest category of soft armor erosion control solutions and how they can benefit your projects,, please contact us.