Hydraulic Mulch Ec 3
Hydraulic Mulch
EC-3
Objectives
EC Erosion Control
SE Sediment Control
TR Tracking Control
WE Wind Erosion Control
NS Non-Stormwater
Management Control
WM Waste Management and
Materials Pollution Control
Legend:
Primary Objective
Secondary
Objective
Targeted Constituents
Description and Purpose
Sediment
Hydraulic mulch consists of applying a mixture of shredded
Nutrients
wood fiber or a hydraulic matrix, and a stabilizing emulsion or
Trash
tackifier with hydro-mulching equipment, which temporarily
protects exposed soil from erosion by raindrop impact or wind.
Metals
Bacteria
Suitable Applications
Oil and Grease
Hydraulic mulch is suitable for soil disturbed areas requiring
Organics
temporary protection until permanent stabilization is
established, and disturbed areas that will be re-disturbed
following an extended period of inactivity.
Potential Alternatives
EC-4 Hydroseeding
Limitations
EC-5 Soil Binders
Wood fiber hydraulic mulches are generally short lived and
need 24 hours to dry before rainfall occurs to be effective. May
EC-6 Straw Mulch
require a second application in order to remain effective for an
EC-7 Geotextiles and Mats
entire rainy season.
EC-8 Wood Mulching
Implementation
Prior to application, roughen embankment and fill areas by
rolling with a crimping or punching type roller or by track
walking. Track walking shall only be used where other
methods are impractical.
To be effective, hydraulic matrices require 24 hours to dry
before rainfall occurs.
Avoid mulch over spray onto roads, sidewalks, drainage
channels, existing vegetation, etc.
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EC-3 Hydraulic
Mulch
Paper based hydraulic mulches alone shall not be used for erosion control.
Hydraulic Mulches
Wood fiber mulch can be applied alone or as a component of hydraulic matrices. Wood fiber
applied alone is typically applied at the rate of 2,000 to 4,000 lb/acre. Wood fiber mulch is
manufactured from wood or wood waste from lumber mills or from urban sources.
Hydraulic Matrices
Hydraulic matrices include a mixture of wood fiber and acrylic polymer or other tackifier as
binder. Apply as a liquid slurry using a hydraulic application machine (i.e., hydro seeder) at the
following minimum rates, or as specified by the manufacturer to achieve complete coverage of
the target area: 2,000 to 4,000 lb/acre wood fiber mulch, and 5 to 10% (by weight) of tackifier
(acrylic copolymer, guar, psyllium, etc.)
Bonded Fiber Matrix
Bonded fiber matrix (BFM) is a hydraulically applied system of fibers and adhesives that upon
drying forms an erosion resistant blanket that promotes vegetation, and prevents soil erosion.
BFMs are typically applied at rates from 3,000 lb/acre to 4,000 lb/acre based on the
manufacturer’s recommendation. A biodegradable BFM is composed of materials that are 100%
biodegradable. The binder in the BFM should also be biodegradable and should not dissolve or
disperse upon re-wetting. Typically, biodegradable BFMs should not be applied immediately
before, during or immediately after rainfall if the soil is saturated. Depending on the product,
BFMs typically require 12 to 24 hours to dry and become effective.
Costs
Average cost for installation of wood fiber mulch is $900/acre. Average cost for installation of
BFM is $5,500/acre.
Inspection and Maintenance
Inspect BMPs prior to forecast rain, daily during extended rain events, after rain events,
weekly during the rainy season, and at two-week intervals during the non-rainy season.
Areas where erosion is evident shall be repaired and BMPs re-applied as soon as possible.
Care should be exercised to minimize the damage to protected areas while making repairs, as
any area damaged will require re-application of BMPs.
Maintain an unbroken, temporary mulched ground cover throughout the period of
construction when the soils are not being reworked.
References
Controlling Erosion of Construction Sites Agricultural Information #347, U.S. Department of
Agriculture (USDA), Natural Resources Conservation Service (NRCS) (formerly Soil
Conservation Service – SCS).
Guides for Erosion and Sediment Control in California, USDA Soils Conservation Service,
January 1991.
Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area
Governments, May 1995.
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California Stormwater BMP Handbook
January 2003
Construction
www.cabmphandbooks.com
Hydraulic Mulch
EC-3
Sedimentation and Erosion Control, An Inventory of Current Practices Draft, US EPA, April
1990.
Soil Erosion by Water, Agriculture Information Bulletin #513, U.S. Department of Agriculture,
Soil Conservation Service.
Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual,
State of California Department of Transportation (Caltrans), November 2000.
Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of
Transportation (Caltrans), November 1999
Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75,
Washington State Department of Ecology, February 1992.
Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional Planning Agency, November 1988.
January 2003
California Stormwater BMP Handbook
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Construction
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