Types of Erosion Control Blankets
An erosion control blanket, or Rolled Erosion Control Product (RECP) come in many kinds of materials, such as:
Straw
Jute
Coconut fibers (coir)
Aspen fiber (excelsior)
Fabrijute
Plastics
Mixed materials
Where Can I Use Erosion Control Blankets?
RECPs are versatile products, and they work well in many different situations, such as:
Streambanks
Channels
Slopes
Erosion control blankets are beneficial on slopes, as they help slow down water flowing over the soil. The faster the water moves, the more erosion occurs.
How Do I Use Erosion Control Blankets?
To install an erosion control blanket, you'll need to dig a small trench to secure the material, fold the edge underneath itself, and secure it with staples. After this, refill the channel to the original soil level. It's recommended you secure blankets to each other if you're using more than one, particularly any loose edges that are upwind.
Temporary Use
One of the best things about erosion control blankets is that they suit temporary situations and permanent ones. If you want to protect a seeded area or need to prevent erosion while working on landscaping, erosion control blankets are among the best solutions. Some blankets degrade over time, so these are an excellent option for a temporary fix.
Permanent Use
Despite their functionality as erosion prevention for temporary situations, RECPs also work well as permanent erosion control measures. If there are areas to your landscaping or geography that you would like to protect, you can permanently secure erosion control blankets to bring erosion levels down.
Alternatives to Erosion Control Blankets
Several alternatives to erosion control blankets exist. However, it is important to get the right product for your situation.
Fiber Logs
Erosion control blankets can be used in rolls, as well as laid out flat. However, you may find fiber logs just as useful. Fiber logs come in any diameter necessary, and they are beneficial on large slopes.
Coming in three main material types, fiber logs are usually made of wheat straw wattle, rice straw wattle, or coir. The primary material is contained within a fiber or plastic net.
Fiber logs soak up water and allow it to pool within the fiber log, rather than continuing to run down your slope. While the water sits in the log, any sediment it carries will settle out and remain inside the log. This reduces erosion and soil loss.
To install fiber logs, you'll need to dig a trench half as deep as the log's diameter and place the fiber log in it. The product needs to be secure, so that soil or water cannot move it. Stake your fiber logs down with wooden stakes at 2 - 3 feet apart right along the log.
Fiber logs come seeded or vegetated, or you may prefer to plant your own. Vegetation is an excellent way to reduce erosion further, and you may find unseeded fiber logs introduce unwanted species to your land.
Grouping logs together at equal distances down the slope increases your erosion control.
You may also want to create your own erosion control solutions, which we'll look at in the next section.
Hydro Mulch
Hydromulching or hydroseeding is an expensive erosion control method, but it is useful for preventing erosion or revegetating high-risk or badly-damaged areas.
A tank containing water, wood fiber, and tackifier sprays mulch over slopes to revive badly eroded areas. If seeds are included in the mix, the technique is known as hydroseeding.
Hydromulching is not recommended during rainy weather. If you don't seed your mulch on application, be aware that unwanted plant species may take root instead.
Temporary Silt Fencing
Silt fences are great for collecting run-off and preventing it from damaging a large area. Silt fencing can be an excellent permanent solution and a temporary one, although it may look too unsightly for a long-term feature.
Real Logs and Rocks
You can make your own erosion control tools by arranging logs, rocks, and bales of straw or hay in areas of high run-off. However, homemade solutions will have gaps, are less permeable than professional-grade equipment, and are not as secure as fiber logs or RECPs.
How to Make Your Own Erosion Control Solutions
Although professional products offer much higher erosion control levels, it is possible to create some erosion control solutions yourself.
Logs, Rocks, and Hay Bales
To make a run-off trap, arrange logs, rocks, or hay bales into lines, much like fiber logs. For better erosion prevention, buffer your row of hay bales, or log, with stones.
Tree Revetments
Useful for preventing streambank erosion, homemade tree revetments offer some protection against the elements. You'll need to set your tree revetment up in dry weather, preferably when the riverbed is dried up.
You will need a duckbill anchor, steel cable, and several trees. Secure the revetment with the anchor, and ensure all branches and trunks are carefully secured with cable. When finished, pull the wire taut, and remove any excess thread.
Tree revetments help slow the stream's speed, reducing the energy the water has to erode the banks.
Root Wads
To create a root wad, you'll need to anchor a log into the bank, preferably when the stream or river is dry or at its shallowest. Next, secure the bottom half of a tree to the log with rebar. Arrange the tree to stick out from the bank with its root wad sitting on the other side of the log.
Root wads deflect the current away from the streambank, provide structural support for the banks, and allow sediment to build up around the roots, further enhancing the bank's stability.
Case Study: Laetoli Footprints
Two types of geotextile helped preserve the Laetoli Footprints in Tanzania from erosion. Initially discovered in the 1970s, the early hominid footprints were reburied until the 1990s, re-excavated, and examined again. With no way of moving the prints to a museum, scientists and archaeologists eventually decided on another reburial, this time incorporating geotextiles into their erosion control measures.
A geotextile was laid directly over the footprints, and then several layers of soil were piled on top. Between one of the upper layers is an erosion control blanket, placed there to slow water run-off. On top of the mound, small rocks and boulders are organized closely. A trench has been left open for maintenance workers to check the effectiveness of the geotextiles.
During the first reburial of the prints, archaeologists didn't use geotextile products. This led to erosion and irreparable damage to some of the footprints. A big culprit in the deterioration of the Laetoli prints was due to acacia seedlings. Workers now monitor the new reburial site for signs of tree seedlings. Another major cause of the erosion of the Laetoli footprints is water, whether rain or run-off. The erosion control blanket in the new site offers a lot more protection so that scientists can study the prints for years to come.
Flexamat and Erosion Control Blankets
Flexamat pioneered the tied concrete block mats and is an expert in erosion control and prevention. Various erosion control blankets can be incorporated as underlayment to Flexamat. The erosion control blankets backings are rolled with the Flexamat, packaged together in rolls.
Flexamat concrete mats are used for a wide range of applications, such as: