Sediment is the leading nonpoint source pollutant in U.S. waterways, and it comes almost entirely from ground that had nothing protecting it during this window: eroding stream banks, disturbed construction sites, and land stripped of vegetation. On some Midwest streams, bank erosion alone contributes as much as 80 percent of the total sediment load moving through the system. Nationally, roughly 80-90 percent of the U.S. ocean shoreline is eroding, which isn’t isolated site failures. They point to the same missing piece: something needs to hold the ground together before plants can do it on their own.
Why the Gap Exists in the First Place
Seed requires time to germinate, and root systems require considerably more time to develop enough depth to resist surface runoff. During this period, bare soil offers no natural resistance to erosion: there is no root mass to bind soil particles together, no vegetative canopy to absorb the impact of rainfall, and no structure to slow water as it moves across a slope or along a bank. Any significant storm occurring during this period places the site under conditions it is not yet equipped to withstand.
This is the specific problem that Bio-D coir solutions by Rolanka International Inc. are designed to address. Coir, the natural fiber derived from coconut husk, is not intended to replace vegetation. Its function is to stabilize the site for a sufficient period to allow vegetation to establish and assume that role permanently.
What the Research Shows
The performance of coir in this application is supported by published research. In a field study measuring surface runoff on a steep slope, a 700 g/m² coir geotextile reduced runoff to 31 percent of the volume recorded on an unprotected plot, a reduction of nearly 70 percent. A separate rainfall-simulation study conducted on a 30-degree slope found that coir geotextile reduced soil loss by up to 99 percent relative to bare ground. These figures are not incremental improvements; they represent the difference between a site that remains stable through its first season and one that requires substantial rework.
The practical significance of these results extends beyond the initial protection period. Coir is fully biodegradable and does not require removal, nor does it leave synthetic residue in the soil. As root systems establish through and beneath the material, the fiber gradually decomposes, returning organic matter to the soil it originally protected.
Where This Applies
- Stream banks are subject to erosion from two directions at once: moving water erodes the base of the bank while surface runoff drains down from above. Once undercutting begins, it typically progresses quickly, and a minor erosion issue can develop into a structural failure within a single wet season.
- Slopes, particularly those recently graded or otherwise disturbed by construction, are subject to continuous gravitational pressure with no mechanism to interrupt runoff. This is the condition most directly addressed by the runoff-reduction data cited above.
- Shorelines are subject to repeated wave and tidal action, a distinct form of stress compared to slopes or stream banks, though the underlying requirement is the same: the ground must be held in place long enough for a root system to establish.
- Disturbed landscapes, whether resulting from mining activity, storm damage, or land clearing, share a common condition. The vegetative structure that previously held the soil in place has been removed, and a temporary substitute is required until new growth restores that function.
The Point Is Temporary Protection
It is worth stating clearly what coir is not. It is not a synthetic liner intended to remain in place indefinitely, and it is not a cosmetic solution intended only to make a site appear complete at the time of inspection. Its value lies specifically in its impermanence. A material that does not decompose, left in the ground indefinitely, eventually becomes a maintenance liability of its own. Coir is designed to break down at approximately the point when it is no longer required.
This is the appropriate standard by which restoration should be evaluated: not the condition of a site immediately following completion of work, but whether that site remains stable after several subsequent storm events, without ongoing intervention.
Working With Rolanka International Inc.
Rolanka International Inc. has manufactured natural coir erosion control products since 1993, supplying contractors, engineers, and land managers working on stream banks, slopes, shorelines, and disturbed sites across the country. Every order includes free technical assistance to help match the right erosion control solution to the specific conditions of your site, whether that’s slope gradient, flow velocity, or wave exposure, so the product is doing the right job from day one. If your project involves a stream bank that keeps losing ground, or a disturbed site waiting on vegetation to establish, our shoreline restoration products are built for exactly that window.
Reach out to our team for technical guidance or a product recommendation based on your site’s specific conditions. Do it right the first time, and give the land the time it actually needs to recover.