How to Handle Erosion Control on Developed Land
Soil erosion, also called leaching, carries away topsoil and can cause degradation if there are no measures to control it. Soil erosion can cause severe effects like sinkholes, mudslides, flooding, and structural damage if it occurs many times without control.
Civil engineers have the skills to assess current erosion or probability of occurrence in the future. A civil engineer will also determine if any existing measures to control erosion are effective. They suggest remedial measures if they do not find adequate soil erosion control methods. Checkpoints when assessing current and probable erosion include inspecting the following:
• Sediment Barriers
• Detention Basins
• Sediment runoffs
• Bare Soil Area
• Condition of Neighboring Properties
• Grade Conditions
• Presence of Silt Fences and Their Conditions
A civil engineer suggests suitable erosion control measures on developed land if the existing controls are weak.
Dewatering is the removal of accumulated rainwater or groundwater from a site using one of these dewatering methods.
• Open Sump Pumping
• Deep Wellpoint
• Eductor Wells
A civil engineer knows if there is a requirement to apply for special permits if the project is massive.
Sediment Control Traps
Sediment control traps (basins) help in erosion control on developed land by reducing water runoff. These units create space for sediments to settle before you discharge the water. Well constructed sediment basins can store storm water for at least two years.
Sloped land causes challenges to erosion control because gravity works against it even on developed land. Vegetation or spread mulch can create some control, but it is still susceptible to ravages or water flow and wind.
Terracing controls soil, vegetation, and mulch from rolling downhill without anything to stop the roll. Terracing involves digging steps across the slope. The steps slow down water and wind flow over the surface. Terraces are catch basins for loose soil. They stop it from rolling downward to the lowest point on the land. Terraces are more efficient when plants provide ground cover.
Construction of Contour Stone Wall
Civil engineers suggest the construction of a contour stone wall in high rainfall areas with a land slope of 15 to 40%. The erosion control wall is more suitable for developed land with gravelly or lateritic soil. Construction cost remains low because loose stones in the locality are the wall materials. Planting grass on the upper side of land improves performance and durability. Grass enhances erosion control by breaking the land slope and reducing runoff velocity. You can do stone pitching on the downstream side and contour bunds if loose stones are not readily available and the area does not frequently receive intense rainfall.
Mechanically Stabilized Earth Walls
MSE walls in recent years have been replacing concrete retaining walls. MSE walls are more straightforward and faster to install for erosion control on developed land than reinforced concrete walls. It is a system that adapts well to various sites, including developed land.
A French drain is an under surface piping (also called drain tile) system that directs water from the surface and ground to an exit. French drains suit slopes of around 1″ drop per 10 ft. of the horizontal run. You can perforate a drain tile to allow the water sip into the soil underneath. The surplus water still flows to a drain’s exit point.
Soil erosion is notorious for degrading and weakening. It is crucial to use all erosion control methods on developed land so that it stays in the initial state as possible.