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Erosion Control Toolbox
Tools
To Combine Specifications
Planning & Design
Improve Soil Health
- Soils Testing
- Local Topsoil
- Imported Topsoil
- Roughen Soil Surface
- Stepped Slopes
- Contour Grading and Slope Rounding
- Decompact Soil
- Soil Nutrients
- Compost (Incorporate)
Improve Soil Health & Provide Cover
Short Term Cover
Long Term Cover
Steep Slope Techniques
- Stepped Slope
- Cellular Confinement
- RECP Flap
- RECP Flap with Brush Layering
- RECP Wrap
- Soil Filled RSP
- Wire Blanket
- Wire Mesh Confinement
Planting
- Plant Selection
- TransPlant Application
- Noxious and Invasive Species
- Drill Seed
- Dry Seed
- Willow Cuttings
- Native Grass Sod
- Liner
- Seedling
- Brush Layering
Stormwater Treatment
Sediment Control
References
Stepped Slopes
What is This Treatment?
Stepped slopes are constructed of a series of small benches, typically between one and two feet in width. Stepped slopes control erosion by breaking up the slope length - reducing both the volume and velocity of stormwater runoff. The steps promote vegetative cover by capturing and retaining loose soil material and moisture.
When to Use This Treatment?
- Use on excavation (cut) slopes composed of rippable material that are 2:1 (H:V) and steeper. For specific allowable slope gradients consult your geotechnical engineer.
- Use on excavation (cut) slopes as flat as 3:1 (H:V) if necessary to provide visual compatibility with other stepped slopes on a project site.
- Caltrans Highway Design Manual Topic 110.2(2)(b) recommends slope roughening techniques such as stepped slopes, trackwalking, scarification, and sheeps foot rolling to minimize erosion and promote plant growth. Review the Roughen Soil Surface webpage for detailed information on other roughening techniques.
- Comply with the requirements in the Highway Design Manual (HDM) Chapter 300, Topic 304.5 Stepped Slopes.
- Comply with the guidance for Slope Roughening/Terracing/Rounding/Stepping provided in Appendix A of the Caltrans Storm Water Quality Handbooks Project Planning and Design Guide.
Consider Using With:
Benefits:
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Reduced stormwater runoff volume and velocity.
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Improved soil, seed, and water holding capacity on steep slope surfaces.
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Improved vigorous long-term vegetation coverage.
Limitations:
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May increase the cost of earthwork activities.
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Requires site accessibility by earthwork equipment.
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May not be practical for sandy soils.
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May not be practical for shallow, rocky soils.
Standards and Specifications
- Use Department Standard Specifications - Section 19 Earthwork.
- Caltrans Highway Design Manual Topic 110.2(2)(b) recommends slope roughening techniques such as stepped slopes, trackwalking, scarification, and sheeps foot rolling to minimize erosion and promote plant growth. Review the Roughen Soil Surface webpage for detailed information on other roughening techniques.
- Comply with the requirements in the Highway Design Manual (HDM) Chapter 300, Topic 304.5 Stepped Slopes.
Plans and Details:
- Indicate stepped slope tread and riser dimensions in a detail on the project plans.
- See Slope Roughening/Terracing/Rounding/Stepping in Appendix A of the Caltrans Storm Water Quality Handbooks Project Planning and Design Guide.
Estimate Information:
- No pricing information is available for stepped slopes.
Guidance:
- Highway Design Manual (HDM) Chapter 300, Topic 304.5 Stepped Slope
- Highway Design Manual Topic 110.2(2)(b)
- Appendix A - Caltrans Storm Water Quality Handbooks Project Planning and Design Guide.
- California Department of Transportation, "Performance of Erosion Control Treatments on Reapplied Topsoil", May 2005.
- Caltrans Erosion Control Webinars
External Links:
- David Steinfield, Scott Riley, Kim Wilkinson, Thomas D. Landis, Lee Riley, et al. 2007. "Roadside Revegetation, An Integrated Approach to Establishing Native Plants" Accessed 2009-07-16
- Michael Hogan, 2009. "Sediment Source Control Handbook, An Adaptive Approach to Restoration of Disturbed Areas" Accessed 2009-07-16.