Soil scientists and contractors working in erosion control know that not all hydromulch and tackifier products perform equally under stress.
When it comes to choosing the right solution for slope stabilisation, two metrics matter most: erosion resistance and infiltration performance. That’s why recent independent C-factor testing of EnviroStraw’s BFM and EnviroBond® formulations offer critical reassurance—both products exceed expectations across a range of high-intensity rainfall conditions.
What is the C-factor and why does it matter?
The Cover Factor (C-factor), as defined by the Revised Universal Soil Loss Equation (RUSLE), quantifies how well a surface treatment protects soil from erosion. A lower C-factor means less soil loss compared to a bare soil baseline—so the lower the better.
EnviroStraw’s BFM and EnviroBond® were each independently tested by Landloch Pty Ltd using rigorous rainfall simulations designed to replicate real-world storm intensities on gradients up to 30%. The results speak for themselves.
BFM: Consistent performance with exceptionally low C-factors
EnviroStraw’s BFM, a premium bonded fibre matrix hydromulch, achieved C-factor values as low as 0.006 for 100% surface cover—among the best in its class. Even at 95% coverage, the C-factor was just 0.008, indicating minimal soil loss under aggressive slope and rainfall scenarios.
Key insights:
- Slope gradients tested: up to 40%
- Rainfall intensities: up to 150 mm/h
- Stable slope lengths: over 500 m for well-constructed 20% gradients
- Comparison: Outperformed other common hydromulches
(C-factors ~0.017–0.018)
EnviroBond®: Powerful binding and water management
EnviroBond®—a hydrocolloid binder designed for use on exposed batters—also demonstrated strong erosion control, with C-factors averaging just 0.013 across all tests. This included performance under simulated 1-in-5 and 1-in-20 year storm events, with no measurable soil loss even at the steepest gradient and highest rainfall intensity.
But erosion control wasn’t the only strength. EnviroBond® also improved infiltration rates by over 44%, allowing water to absorb into the soil faster and reducing runoff volume. This dual benefit helps rehabilitate soil structure while reducing the risk of rill formation.
Key results:
- C-factor range: 0.004–0.023 (avg. 0.013)
- Infiltration rate increase: From 54.1 mm/h (bare soil) to 78.1 mm/h (treated)
- Plot gradients: 10%, 20%, and 30%
- Rainfall intensities: Up to 200 mm/h
What this means for contractors and engineers
If you’re designing for batters, embankments or disturbed commercial sites, both BFM and EnviroBond® offer scientifically validated, field-ready solutions. Their tested resistance to erosion—paired with their infiltration advantages—means fewer call-backs, better site outcomes, and stronger project reputations.
And because both products are Australian-made and backed by soil science, they meet the needs of contractors who want reliable performance and local supply.
Want to know more?
If you’re looking for support on product selection or tailored advice on stabilising your next site, get in touch.