Erosion can cause devastating damage to your home, property, or construction site, which is why finding an effective way to control erosion is a primary concern for anyone hoping to preserve a landscape or complete a successful build on solid ground.
Before you tackle the erosion itself, however, it’s important to understand the definition of erosion, what causes erosion, what type of erosion you’re dealing with, and how to choose the best method for controlling it.
What Is Erosion?
You were probably introduced to a rudimentary erosion definition as a kid, but how much do you really know about this complex process?
In a nutshell, scientists define erosion as a process by which the surface of the earth gets worn down either by natural elements like ice and wind or by manmade interactions such as poor land management techniques at a faster rate than the soil or rock is formed.
When only natural elements are involved, erosion is generally a slow process that can create massively impressive formations. The Grand Canyon is an extreme example of steady, prolonged erosion.
Other erosion examples include:
- Caves.
- Riverbanks.
- Coastlines.
- Cracks in rocks.
- Landslides.
Some of the most devastating types of erosion involve people’s homes and properties. Remember the infamous Dust Bowl of the 1930s?
The Dust Bowl occurred because people moved to the Great Plains and started plowing the land, which was never ideal for farming. After a few short droughts, people mistakenly believed there would be enough rainfall to sustain future crops, so they broke up the prairie soil and destroyed native grasses in order to plant wheat.
Unfortunately, a 10-year drought settled over the prairie which quickly dried up the topsoil. Once all that freshly planted wheat died, there was nothing left to hold the soil in place.
As a result, a series of dust storms swept through and damaged the prairie’s ecology and agriculture. Entire farms were covered with sand and turned to desert. Cattle were found dead with dust coating their stomachs. Residents coughed up clumps of dirt from breathing in dust. The effect was so extensive that dust storms blew Kansas soil all the way to New York City.
To this day, the prairie region hasn’t fully recovered. And the entire event could have been avoided if settlers had accounted for the region’s history of droughts, utilized different farming methods, and not overworked or stripped the land.
Sure, the Dust Bowl is an extreme example of an erode definition, but it’s given us a clearer understanding of the importance of responsible agricultural practices and construction techniques that can help us become better stewards of our environment.
Types of Erosion
Now that you have a better understanding of this natural process, you’re probably wondering what causes erosion? Land erosion happens in a variety of ways, the main ones being:
- Water Erosion
- Wind Erosion
- Glacier Erosion
- Permafrost Erosion
- Human Cause Erosion
Water Erosion
Water erosion results from flowing water removing soil material. The soil can be impacted by raindrops, suspended in runoff, or affected by ocean waves. Both the chemicals in the water and the force that make up the flow can break down rocks and change the shape of riverbanks.
There are four types of accelerated water erosion:
- Sheet erosion, which occurs when soil particles resting on a downslope are impacted and detached by rainwater. The soil detaches in a sheet-like formation that flows overland as a whole piece or uniform layer. Imagine pulling a sheet of sod across the yard and that’s pretty much what sheet erosion looks like. Sheet erosion typically occurs on sites with poorly consolidated soil material, such as a recently plowed field.
- Rill erosion, which refers to soil removal through cutting or tilling numerous channels where runoff can concentrate, resulting in soil loss and eroded fields.
- Gully erosion, which results from water cutting into the soil along the flow line, exposing natural drainage-ways, vehicle ruts, animal trails, and crop rows. Common farm equipment cannot cross deep gullies.
- Tunnel erosion, which is the movement of excess water through a dispersive subsoil such as old root holes, animal burrows, or surface cracks.
Wind Erosion
Although the wind might not be strong in your area, wind can still transfer light objects like pebbles and rocks until they run into landforms. Over time, these tiny particles can start to erode whatever they hit.
Glacier Erosion
Also known as ice erosion, glacier erosion occurs when huge bodies of ice transfer big chunks of rock. The combination of ice, water, and sediment creates one impressive eroding entity.
Permafrost Erosion
In northern areas of the Northern Hemisphere, there is currently an accelerating problem of the permafrost melting, and eroding into lakes and sinkholes. Permafrost is the historically “permanently frozen soil”. The frozen ice is actually a constituent of the soil itself, lending structure and rigidity to the silt-rich soil.
Due to climate change, the ice is melting, leaving a very unstable layer of loamy or silty soil which is carbon-rich and contains ancient microorganisms. As the microorganisms reanimate, they produce gases such as methane, which erupt from the soil and create voids which fill with melted water and quickly form new lakes or sinkholes. The Siberian tundra is currently experiencing this phenomena at an unprecedented rate; primarily due to climate change.
Human Cause Erosion
Soil erosion occurs a number of ways. The most egregious would be human-induced causes. These include construction, faulty farming (tillage), mining, deforestation, overzealous herbicide use, and cattle overgrazing. The usage of herbicides or allowing livestock to overgraze cause ground cover vegetation to die, leaving bare soil. The bare soil is easily eroded away by natural means.
Something as simple as not utilizing appropriate engineering principals or procrastinating with erosion mitigation utilities on ditches or roadways will inevitably lead to natural erosion. The natural causes of soil erosion would include precipitation, wind velocity, soil characteristics, hydrology, and slope gradients. The eroded topsoil will ultimately inundate the planned drain system perhaps leading to enormous damages to surrounding land.
5 Ways to Prevent Erosion
Fortunately, there are effective ways to control erosion. Your specific solution will depend on the factors causing the erosion as well as its severity. Taking these erosion control measures can help minimize construction costs and keep your home safe from harm.
Coir Products
Coir is a type of material made from natural coconut fibers that are ideal for erosion control. Coir erosion products are available in numerous shapes and sizes, including mats, blocks, wattles, logs, and silt checks. They’re so effective, in fact, that coir has been used to control coastal and riverbank erosion. Plus, since they’re all-natural, coir products are a more aesthetically pleasing choice than most erosion prevention measures.
Articulated Concrete Blocks
While not as natural as coir, concrete blocks are available in just as many shapes and sizes. They can even form interconnected grids to prevent erosion on waterway embankments. The biggest downside to articulated concrete blocks, however, is that they look best protecting manmade structures like boat ramps and channels.
Dust Control
Utilizing dust control methods like silt fences and misted water keeps topsoil moist enough to resist dreaded wind erosion.
Riprap
Riprap is a common erosion control method that uses large, interlocking stones as barriers. These structures are mainly placed on unstable slopes with seepage issues that have already eroded.
Soil Nails
One of the more surprising methods of erosion prevention is soil nailing, which involves drilling and placing steel bars deep into the soil and capping them with a facing that creates a retaining wall.
No matter the causes of erosion you’re dealing with, finding the right prevention technique is key. If you’re looking for an environmentally friendly, superior performing, cost effective and affordable option, consider coir-based erosion products.
Sources:
https://www.nps.gov/grca/planyourvisit/upload/life_geology.pdf
https://www.sciencedirect.com/science/article/abs/pii/S1875963715000798
https://www.nda.agric.za/docs/Infopaks/Soilerosion.pdf
https://www.nrdnet.org/sites/default/files/soil_erosion.pdf
https://nptel.ac.in/courses/105101010/downloads/Lecture06.pdf
https://www.erosionpollution.com/Coir.html
https://www.geosolutionsinc.com/products/erosion-control-articulated-concrete-blocks.html
http://lshs.tamu.edu/docs/lshs/end-notes/riprap-2389874252/riprap.pdf