- Barrier Aesthetics
- Blue Star Memorial Highways
- Classified Landscaped Freeways
- Community ID
- Context Sensitive Solutions
- Erosion Control Toolbox
- Gateway Monuments
- Main Streets
- Mission Bells
- New Product Review
- Policy and Procedures
- Roadside Toolbox
- Safety Roadside Rest Area System
- Scenic Highways
- Transportation Art
- Visual Impact Assessment Outlines
- VIA Training
- Water Conservation
Erosion Control Toolbox
To Combine Specifications
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?
Mulch-like blanket of medium-coarse stable and mature compost, typically 2" thick. Note that compost blanket is a coarse woody product, not the fine, screened compost product typically used as a soil amendment.
Where to Use This Treatment:
- Typically applied on slopes 1.5:1 (H:V) and flatter. The following application rates are suggested:
- Slopes 1.5:1 (H:V) - 1" maximum thickness.
- Slopes 2:1 (H:V) - 2" maximum thickness.
- Slopes 3:1 (H:V) - 3" maximum thickness.
- Slopes 4:1 (H:V) - 4" maximum thickness.
Improved protection from raindrop splash erosion.
Reduced competition from weed species.
Reduced stormwater runoff volume and velocity.
Improved infiltration rate.
- Conserves soil moisture.
Improved soil biology - activity by bacteria, mycorrhizal fungi, nematodes, protozoa, microarthropod and earthworms.
Improved soil nutrient levels and nutrient cycling.
Improved potential for vigorous long term vegetation coverage.
- Requires temporary storage space within the project limits to stockpile materials.
Applying high levels of organic materials may not be appropriate in arid regions of the state.
- Compost can be blown on a site together with seed in a single-step, cost effective erosion control treatment.
- Compost can also be blown in place together with a tackifier to help hold the material in place on steeper slopes.
- Medium coarse compost has a a sieve size of greater than 1/2" and less than 3" in length. See specification for detailed dimensions.
Caltrans compost suppliers must be participants in the United States Composting Council's (USCC) Seal of Testing Assurance (STA) program. A list of current STA program participants is available at: US Composting Council (USCC) Seal of Testing Assurance (STA) Program Participants
- 2010 Standard Specifications (See Section 21-1.02M and 21-1.03L Compost
- 2010 Revised Standard Specifications (RSS)
Common Compost Application Rates
|Compost Depth||Cubic Yards/Acre||Pounds/Acre||Tons/Acre|
Average Compost Weight = 800 lbs/cubic yard (1050 lbs/cubic meter).
Compost Application Methods
The large quantities of compost required for a compost blanket can be applied to a flat project site using a dump truck and a bulldozer. Projects with steep slopes, or areas inaccessible by vehicles require alternate methods - the most common method being a pneumatic blower truck.
Working like a vacuum cleaner stuck in reverse, a pneumatic blower truck can rapidly applies compost to steep slopes or constrained areas that are unreachable by traditional equipment. A 40 cubic yard blower truck holds roughly 35 cubic yards of compost, and applies this material at a rate of about 35 cubic yards/hour. A single truck should be able to apply a 1" thick compost blanket over a 2-acre site (280 CY total) in a single working day. The typical truck has a hose that can reach 300 feet - defining the farthest extents of application from the roadway. A rough estimate of cost for labor and materials for this work would run from $5,000 - $8,000 per acre. This price estimate does not include seed.
Consider Using With:
Combine with other Rolled Erosion Control Products to hold compost in place on slopes steeper than 2:1 (H:V).
To effectively treat sites with compacted, sterile or poorly draining soils, consider combining this treatment with
Plans and Details:
Examples of how to specify the use of Compost on the project plans:
- Click here to view current awarded bid prices for Compost.
- Use BEES code 210600 Compost.
- Click here for a 1997 study on Soil Stabilization and Erosion Control pricing.
This study establishes parameters for compost use based on performance criteria including soil type, climate, slope length and steepness, aspect, and location. The research addresses how compost affects water quality and erosion, and if compost improves the establishment of permanent vegetation cover.
Regeneration of Nitrogen Fertility in Disturbed Soils Using Compost
Graphs nitrogen release from various composts and compares compost release rates with two native topsoils.
- 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.
- US Composting Council Seal of Testing Assurance, Compost Producer Participants Accessed 2009-07-16.
- Compost Use for Landscape and Environmental Enhancement Manual
The California Integrated Waste Management Board's Compost Use for Landscape and Environmental Enhancement publication provides objective information regarding compost use in landscape plantings and environmental applications.
- Thomas D. Glanville, Tom L. Richard, Russell A. Persyn, Impacts Of Compost Blankets On
Erosion Control, Revegetation and Water Quality ay Highway Construction Sites in Iowa, April 2003.
- US EPA. 2000. Infiltration Through Disturbed Urban Soils and Compost-Amended Soil Effects on Runoff Quality and Quantity, 2000.
- USEPA. 1998. National Pollutant Discharge Elimination System (NPDES), Compost Blankets April 1998.