Appendix B: Bioengineering for Streambank Erosion Control -- Guidelines
"The Stinger" was used on a bioengineering project on the upper Missouri River by the
Omaha District, Corps of Engineers, in April 1996, to place dormant willow posts between
and landward of large haybales used in the toe zone, as mentioned briefly above. "The
Stinger" was used for efficiency and ease of construction (Figure 36).
Figure 36. Use of "The Stinger" to create pilot holes for
dormant willow posts on the upper Missouri River (CE project,
Omaha District).
There are constraints in using willow posts and several questions to be addressed in the
process of planning if this method is considered. These are noted by Roseboom (1993), but
have been modified here:
a.
Does sunlight fall directly on the eroding bank? Willows must have at least partial
sunlight to grow.
b.
Is bedrock close to the surface? The soil should be at least 4 ft deep; this can be
checked with a probe.
c.
Are lenses of fine sand exposed in the eroding bank? If so, piping may be a problem
and other methods of controlling piping need to be addressed for the dormant post
method to be successful. This may be done through the brushmattress technique
mentioned above in combination with a geotextile filter or it could be done by use
of the vegetative geogrid technique mentioned above.
d.
Is the stream channel stable upstream of the erosion site? If the stream cuts behind
the upper end of willow posts, the entire bank will erode.
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