What construction methods minimize erosion?
Written by
Benjamin Miller
Reviewed by
Prof. Charles Hartman, Ph.D.Construction sites accelerate soil erosion beyond natural rates. You need to discard harmful methods and adopt effective practices so that your operations don't pollute waterways with silt from sediment. Do so by installing sediment basins to trap any runoff and combining them with geotextile mats on exposed soil. Make sure you earthmove during the dry seasons. I protect rivers and streams from construction sediments by doing these and other practices on highway projects.
Sediment Basins
- Position at lowest site points to capture runoff
- Size basins to hold runoff from 25-year storms
- Install silt curtains to trap 90% of sediment
- Clean out accumulated sediment monthly
Geotextile Mats
- Roll out biodegradable blankets on exposed slopes
- Anchor edges every 1 meter with stakes
- Reduce erosion by 70-85% during establishment
- Allow vegetation growth through mesh openings
Phased Land Clearing
- Clear only areas needed for immediate work
- Maintain natural buffers between zones
- Revegetate completed sections within 14 days
- Limit exposed soil area by 60-80%
Sediment basins: Construct these before the rainy seasons. Excavate basins 1-2 meters deep and line them with an impermeable liner. Your basins will then trap tons of sediment. Last year I stopped 50 truckloads of silt headed to the river. It helps preserve downriver underwater ecosystems.
Install the geotextile mats right after grading. Use biodegradable jute or coconut fiber. Staple the mats securely down on steep slopes and forget about your exposed soil, which will now stay protected from being washed away as your germinating seeds grow through it and become rooted in the earth. I typically geotextile all graded areas within 24 hours.
Plan excavation projects at the correct time (dry period). Avoid performing work on moist soils (with a moisture content exceeding 30%) whenever possible. Using less compactable equipment reduces soil compaction. Adjust your schedule according to weather forecasts. Simply doing this will reduce erosion by 50%.
Use phased clearing with buffer zones, for example, clear only the area where you're actively working on the site. Leave a 10-meter strip of vegetation along the border of the cleared areas. This will help to retain your site's natural drainage. I mark up the site map before we break ground. "Look at the sediment! This greens up and really isolates... bang!"
Read the full article: 10 Proven Ways to Prevent Soil Erosion
