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Erosion Control Toolbox
Planning & Design
Improve Soil Health
- Soil Rehabilitation
- Local Topsoil
- Imported Topsoil
- Roughen Soil Surface
- Stepped Slopes
- Contour Grading and Slope Rounding
- Decompact Soil
- 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
- Soil Filled RSP
- Wire Blanket
- Wire Mesh Confinement
- Plant Selection
- TransPlant Application
- Noxious and Invasive Species
- Drill Seed
- Dry Seed
- Native Grass Sod
- Brush Layering
Low Impact Development
- Sidewalk Stormwater Planter
- Sidewalk Stormwater Tree Trench
- Parking Stormwater Planters
- Permeable Paving
- Additional Resources
What is This Treatment?
Compost socks consist of tubular netting filled with compost.
Where to Use This Treatment?
Place on erodible slope faces at regular intervals, and at the slope top, toe, and at grade breaks, aligning compost socks with the slope contours.
Biodegradable socks are available in both 8-inch and 12-inch diameters in both cotton (white) and burlap (beige). Both burlap and cotton socks will likely function up to 12 months, depending on climate and weather conditions.
8-inch diameter socks work well on slopes up to 2:1 (H:V).
12-inch diameter compost socks are too heavy for the middle of 2:1 slopes, however they work well at the toe.
Compost socks are typically spaced as follows:
- 10 feet apart for slopes steeper than 2:1 (horizontal:vertical)
- 15 feet apart for slopes from 2:1 to 4:1 (horizontal:vertical)
- 20 feet apart for slopes from 4:1 to 10:1 (horizontal:vertical)
- 50 feet apart for slopes flatter than 10:1 (horizontal:vertical)
For additional guidance, contact your District Stormwater Coordinator and the Storm Water Quality Handbook - Project Planning and Design Guide (May 2007).
Reduces slope length.
Reduces stormwater runoff volume and velocity.
Intercepts runoff and releases it as sheet flow.
Reduces the amount of sediment in runoff.
Sock can be slit and removed at the end of the project leaving the compost in place to improve soil quality and provide for vigorous long term vegetation coverage.
- Some Regional Water Quality Boards may require compost socks to be setback from a water body 303d listed for nutrients.
- Sock must uniformly contact ground surface for maximum effectiveness.
- Difficult to install securely on steep or rocky slopes.
- 12-inch diameter compost socks are limited to being placed at the toe of 2:1 (H:V) slopes.
- 2010 Caltrans Standard Specifications - Section 21 Erosion Control
- SSP 21-1.02Q Use only if Compost Sock netting must be plastic. Do not use where wildlife may become entrapped
- 2010 Standard Special Provisions Index
Plans and Details:
- 2010 Standard Plans - See Standard Plans for Section 21 Erosion Control
- 2010 Erosion Control Legend/Quantity Sheet for Compost Sock
- Click here to see sample Erosion Control project plans
- Click here to see recent costs for Compost Sock
- Use BEES code 210360, Compost Sock.