What Causes Soil Erosion?
Erosion of soil over time is a natural part of our rural landscapes everywhere. Take a road trip and I bet that you will see small hillsides that have fallen away. Water is the biggest contributor to the erosion process. Major rains that saturate the ground and destabilize the hill over time eventually cause sections to loosen and eventually break off. Erosion is ok until it occurs in more urban areas that must take more preventative measures in order to protect the assets that make up a civilization. So, the importance of land erosion control comes down to protecting what we value, whether it be buildings, roadways or waterways, by implementing measures designed to withstand the effects of water exposure and slow down the erosion process.
Why Soil Erosion Could be Dangerous
When a construction project begins and the land is cleared, one of the most important concerns for the area is that it drains well, and that erosion is kept to a minimum. Plans to make sure that the water is diverted properly includes sloping the land, usually 2-5%, and is essential when developing a new site for water to drain naturally. When problem spots develop the most effective resolution would be to re-grade and re-slope to ensure that water is draining correctly. These measures can improve any area to drain properly and keep erosion to a minimum.
How Erosion Control Protects Construction Sites
Construction projects must use erosion control measures in order to protect what is being built as well as the surrounding area. Temporary measures are taken before any work begins because the ground will become disturbed. The weight of the heavy equipment along with the digging activity causes the soil to loosen, sometimes break away and essentially causing accelerated erosion. The loose sediments must be contained within the job site, so silt or filter fencing is used to capture the loose sediments and keep them from getting into the local water sources. The biggest concern for the surrounding environment of a site is the effect that construction has on water flowing and carrying hazardous materials into creeks, storm drains in general any local water source than can be harmful to people or animals. For that reason, hiring a professional company whose commitment to preserving our environment is something to keep in mind.
Types of Erosion Control
RETAINING WALLS – Many man-made ponds and lakes use retaining walls where the water meets the shore. This erosion control measure is used so that the underlying soil doesn’t erode into the water. Using a retaining wall is also very effective around residential lakes/ponds. These features usually have a lot of activity around them due to being designed with amenities like jogging trails or parks right next to them. Keeping the banks nice and secure helps protect those features for years of enjoyment.
DETENTION PONDS – The construction of detention ponds can help manage large amounts of rain by collecting runoff water and then slowly releasing it to its proper source. This process helps protect the areas that can’t handle the amount of rainwater and are subject to flooding. The ponds are designed with erosion preventative measures that the areas that drain to it, don’t have. These types of ponds are useful in larger residential and commercial areas and are part of the flood control measures designed to move water out of the high traffic areas.
DRIVEWAY CULVERTS – Driveways can be built so that they help water flow rather than act as a damn. If the driveway isn’t used too often a simple culvert using a pipe covered with dirt can be installed so that the water can flow underneath. Driveways that carry more traffic or heavier loads will require a more sophisticated design, sometimes using large concrete culverts that will be used safely and last for many years. Whichever design is chosen the purpose of the culvert is a very effective erosion control measure for your driveway area.
ROADWAY DITCHES – Roadways and their surrounding areas are subject to erosion, so it is very important to design the area for water to be dispersed correctly. Most roadways are built with ditches on each side that are used for water to flow to other sources during rainy times. These ditches work very well in keeping the water away from the road until, erosion has caused an issue. A popular way to create a more solid grounding is to install geo-matting which has many different thick gridded sections designed to retain whatever material is being used. Dirt, gravel or even seeded soil can be used to create a solid slope that will function properly for years to come. Planting vegetation can also help slow down and control the erosion process because of the roots ability to strengthen the footing.
DRAIN DITCHES AND BAYOUS – Speaking of flood control measures, large drain ditches and bayous are a very important part of any development. They are used to move larger amounts of water downstream but many times movement can be slow and attribute to erosion. In order to be effective these larger flood control means must be carefully designed using a combination of erosion control measures. Geo-netting and/or erosion control blankets can be used in combination with rip-rap or rubble along the streambed and slopes, so that the water flow doesn’t constantly take away the soil when storm waters come through.