Hydraulic Mulches and Tackifiers
Hydraulic erosion control products are mulches and glue-like substances that are sprayed with water onto the soil surface.
Comments requested on new draft hydraulic mulch specification
MnDOT is re-writing the standard specification for hydraulic mulches and tackifiers. Click the link below to view the draft specification. Comments and questions can be directed to Steve Gebauer (Steven.gebauer@state.mn.us). Please send comments by April 10, 2026.
DRAFT 3884 Hydraulic Erosion Prevention Products
As part of the re-writing of the standard specifications, a performance standard will also be included to add instructions, clarity, and process for handling the APL. Please click the link below to view the draft Performance Standards process document.
DRAFT Performance Standards Process to APL for HEPPs
Summary of changes to Specification 3884
Tackifier
- requirements have been simplified and categories reduced
Hydraulic Mulches
- will consist of two categories, Bonded and Reinforced Fiber Matrix
- target application rates will vary based on slope and soil roughness
- are not allowed to have any added dye, pigment, or other colorant
- cannot contain any plastic fibers and must be completely biodegradable
- See the Performance Standards for language on tests being considered
- must be tested using ASTM D8298 and achieve a certain C-factor
- See the Performance Standards for language on criteria requirements
- Added Moisture Holding criteria with Bonded and Reinforced Fiber Matrix
Organic Fiber Matrix
- Moisture content increased from 15% to 30%
Mineral Matrix
- This category is new to the spec. It is a cementitious slurry used for temporary stabilization of inorganic soils
Summary of changes to Specification 2575
Change to Specification 2575 in multiple locations will include language as follows:
Replace Bonded Fiber Matrix with Reinforced Fiber Matrix when rain is forecasted within the next 36 hours with a 50 percent or greater chance. Use Reinforced Fiber Matrix for any application on or after October 1st. See 2575.5 of this special provision for payment information.
C.3 Type 4 Mulch – Bonded Fiber Matrix will replace Stabilized Fiber Matrix
E.2.b – Type Mulch will be deleted
E.2.c – Type Stabilized Fiber Matrix will be deleted
M Rapid Stabilization
Table 2575.3-3 Rapid Stabilization - Method 2 and Method 3 – Bonded Fiber Matrix will replace Stabilized Fiber Matrix
Expected timeline
New specs will be incorporated into project lettings about 9 months after the final spec is released. This will also give manufacturers time to conduct testing and apply for the Approved Products List. Actual use on construction projects will likely occur 12 months after the final spec is released because of the time lag between letting, contract award, and starting work.
HECP Applicator Certification
MnDOT co-sponsors a certification class for contractors who will be applying hydraulic erosion control products (HECP). This normally occurs every three years. Contractors who missed the MnDOT training can request training and certification from their HECP manufacturer or vendor.
Training requirements are explained in the following link:
Standard Specification
Requirements for Hydraulic Mulches and Tackifiers are found in the MnDOT Standard Specifications for Construction, available on the MnDOT Spec Book web page. Open the document and search for the following:
- Installation requirements: 2575 Establishing Turf and Controlling Erosion (See 2575.3 E Placing Hydraulic Erosion Control Products)
- Material Requirements: 3884 Hydraulic Erosion Control Products
Design Guidance
Information on choosing the right HECP for the situation can be found in Chapter 13 of the Facility Design Guide. Look for section 13I and Exhibit 13I-2