Another streambank stabilization method is live siltation.
What Is Live Siltation?
Live siltation is a streambank stabilization technique that relies upon revegetation. It is typically used in conjunction with other toe-of-slope protection that sit below ordinary high water, such as a coir log or cabled spruce trees. The result of live siltation is often a brushy living system at the edge of the water. In order for live siltation to work effectively, it is critical to know the high water point.
Live siltation only works in areas where there is shallow water and a slope. Those installing deep-water pipelines will want to look into other methods. Similarly, live siltation works best in areas of low velocity where silt can be deposited quickly. If done correctly, live siltation methods can create spaces for riparian vegetation.
To implement live siltation, Submar uses natural stone, logs, root wad revetments, or willow wattles. The branches will be dormant, but they will have side branches that will allow vegetation. It is also critically important to use native vegetation as it is more likely to take hold. There is a chance that non-native plants will not grow, rendering the project unsuccessful.
Why Encourage Vegetation Growth?
Vegetation serves as a natural erosion protector. Without vegetation, topsoil will run down-slope, resulting in significant erosion. Vegetation, however, locks topsoil into place and prevents runoff, naturally cutting down on the rate of water flow.
Combining Live Siltation with Other Methods
To get the most out of live siltation methods, you may want to consider combining the practice with other types of streambank stabilization. Installing Submar articulated concrete block mats at the highest points of embankments, for instance, not only secures topsoil but also encourages vegetation.
Using articulated concrete block mats at the higher points of the embankment cuts down on the risk of erosion. If the higher areas of the embankment are not secured, runoff will continue down toward the stream, picking up momentum along the way. The higher up on an embankment that companies secure, the more success they will have stabilizing a stream. Then, the live siltation method acts as a measure of last resort near the waterline.
In addition to Submar’s articulated concrete block mats, other methods worth consideration along with live siltation include:
• Rock toes
• Fiber rolls
• Live Fascines
• Brush Mattresses