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Contractor Resources
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
- Incorporate Materials
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
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Planting
- Plant Selection
- TransPlant Application
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- Liner
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Stormwater Treatment
Low Impact Development
- Overview
- Sidewalk Stormwater Planter
- Sidewalk Stormwater Tree Trench
- Parking Stormwater Planters
- Permeable Paving
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Sediment Control
References
Stepped Slopes
What is This Treatment?
This technique consists 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 the velocity of stormwater runoff. The steps promote vegetative cover by capturing and retaining loose soil material.
When to Use This Treatment?
- Use on excavation (cut) slopes between 2:1 and 1.5:1 (H:V) as recommended by Caltrans Division of Engineering Services (DES) Office of Geotechnical Design.
- For slopes steeper than 2:1 (H:V) a Geotechnical Design Report should be prepared by Caltrans Division of Engineering Services (DES) Office of Geotechnical Design. In addition, a preliminary evaluation may be required.
- 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 potential for establishing vegetative cover on steep cut slopes.
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 or rocky soils.
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For cut slopes only.
Standards and Specifications
- Use Department Standard Specifications - Section 19 Earthwork. A Standard Special Provision for (SSP) this work is not required - show the stepped slopes on the earthwork and grading plans.
- 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.
Updated 11-21-2012