Type of Soil Erosion & Soil Erosion Prevention Strategies

Type of Soil Erosion & Soil Erosion Prevention Strategies

When undergoing a construction project, there are several permits that you will need to worry about. One of the most important permits is a Construction General Permit, which will enable your site to discharge excess stormwater into a point discharge system.

To acquire this permit, you often have to develop an ongoing stormwater management plan, known as a SWPPP. This document outlines various sources of pollution and erosion control measures designed to protect the native landscape and surrounding ecosystem.

While we tend to think of stormwater as just a flooding risk, uncontrolled runoff can result in erosion and, even worse, sedimentation. Once that top layer of soil is stripped, it loses much of its nutrients, becomes more difficult to reestablish, and allows loose sediment to mix with stormwater and pollute it.

However, site managers need to be aware of several types of soil erosion that can threaten local ecosystems. This guide will discuss each type of soil erosion, as well as general prevention strategies, including an integrated erosion control strategy.

Understand the Types of Soil Erosion

Soil erosion can be caused by several things, including wind, rain, and overfarming. However, by understanding the types of soil erosion we witness in real-time, we can act to reverse their effects and even reestablish the native topsoil.

1. Sheet Erosion

Sheet erosion is perhaps the most common form of erosion, and it occurs when heavy rainwater or melting snow rushes over a shallow surface and takes away dislodged particles.

Think of a muddy marsh where the grass has become sparse due to excess moisture in the soil. Sheet erosion often occurs on slopes or areas that are impacted by continuous splash rain.

Over time, sheet erosion can remove much of the nutrient-rich topsoil and leave the soil vulnerable to even greater erosion, which will allow loose sediment particles to begin seeping out and mixing with the runoff.

Sheet Erosion Prevention

There are several ways to prevent and even reverse the effects of sheet erosion.,

  • Site Grading: Reducing the angle of a slope can prevent water from channeling in one area and prevent any wave effects that may dislodge or erode the top surface.
  • Mulching and Cover Crops: Reestablishing vegetation via mulching, hydroseeding, or cover crops will allow for greater infiltration of water into the soil and thicker resistance against topsoil erosion.
  • Stormwater Pipe: Redirecting stormwater flow from vulnerable areas, such as slopes, using drainage pipes can help protect vulnerable soil.

2. Rill Erosion

Beneath a slope where it begins to flatten, site managers need to worry about another type of soil erosion: rill erosion. This erosion occurs when small grooves are carved into the soil due to an excessive flow of rainwater or snow settling at the bottom of a slope.

If not checked, rill erosion can lead to an accelerated loss of surrounding soil and each weather event will only make the grooves in the soil deeper and worse.

Rill Erosion Prevention

Preventing rill erosion often requires creating alternative ways to drain and divert stormwater so it doesn’t settle at the bottom of slopes.

  • Terracing: Creating stepped levels on slopes reduces water speed and prevents the formation of drills.
  • Grassed Waterways: Establishing grass-covered channels allows water to flow without causing soil erosion. Additionally, deep-rooted perennial trees can help keep soil stable at the bottom of slopes.
  • Silt Fences: Silt fences established on slopes can slow down the velocity of stormwater runoff and even be used to divert some stormwater away to areas with greater vegetative cover.

3. Gully Erosion

In extreme cases, when rills are not tended to, they can eventually result in the soil being washed away and forming massive gulleys. This can create dangerous hazards on farms, construction zones, or residential areas where this is allowed to occur.

Not only can gulley erosion make land unusable, but it can also contribute to significant sedimentation of rivers and nearby streams.

Gully Erosion Prevention

Preventing gulley erosion requires actively repairing the gulley and preventing further sediment from washing away.

  • Check Dams: Installing small barriers in gullies slows water flow and promotes sediment deposition.
  • Revegetation: Planting grasses, shrubs, or trees stabilizes soil and prevents further gully expansion.
  • Gully Plugging: Using rocks or other materials to fill gullies can prevent them from growing larger.

4. Wind Erosion

On the opposite end, too little rainwater can also leave the ground vulnerable to wind erosion.

While dry and arid conditions are often associated with wildfires, wind erosion can be a significant effect of a lack of rainfall and create hazardous conditions. Wind erosion is not just reserved to the mid-west or west either; wind erosion can occur anywhere where the right conditions present themselves.

During wind erosion, the topsoil can become loose and blow away dirt and sediment that can impact nearby crops and vegetation. Wind erosion can also contribute to air pollution, which can compromise worker safety and that of the community.

Wind Erosion Prevention

Preventing wind erosion requires careful ground cover and also ensuring that nearby soil still gets a fair degree of moisture.

  • Surface Covering: Using mulch, crop residues, or geotextile blankets to shield soil from direct exposure to wind.
  • Windbreaks: Planting rows of trees or shrubs reduces wind speed and protects soil from being carried away.
  • Soil Moisture Management: Keeping the soil moist through irrigation or organic amendments reduces its susceptibility to wind erosion.

5. Streambank Erosion

Streambank erosion is similar to sheet erosion and takes place along the banks of rivers and streams, where flowing water gradually wears away the soil. This process can be accelerated by heavy rainfall, flooding, or human activity.

Streambank Erosion Prevention

Protecting banks and shorelines often requires constructing barriers made out of different materials, depending on their location and application.

  • Ripraps: Placing large rocks along streambanks absorbs water energy and prevents soil from being washed away.
  • Vegetative Buffers: Planting native vegetation along streambanks stabilizes soil and reduces erosion risks.
  • Streambank Shaping: Reshaping steep banks into gentler slopes reduces water velocity and pressure on the banks.

Integrated Erosion Control Measures

For comprehensive erosion management on worksites, urban centers, farms, and residential neighborhoods, an integrated plan will be necessary to provide temporary and permanent protection against erosion.

For assistance in installing, managing, or inspecting any erosion control measures you provide, contact the experts at Valor Environmental today.

FAQs

What are the main causes of soil erosion?

The primary causes of soil erosion are water, wind, and human activities such as deforestation, overgrazing, and improper land use.

Can vegetation alone prevent soil erosion?

Vegetation is an effective erosion control measure, as it stabilizes soil and reduces water and wind impact. However, in severe cases, additional methods like terracing or ripraps may be needed.

Are there government programs to help with erosion control?

Yes, many governments offer conservation programs, grants, and technical support to help landowners implement erosion control measures.

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