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 Selection of Site-specific Stabilization Techniques
Water quality
Increase in turbidity during construction.
Decrease in turbidity after construction, since sediment input
from bank erosion and failure will be reduced.
Increase in water temperature if significant shade canopy is
permanently removed.
Decrease in water temperature if an unvegetated bank is
stabilized and vegetated.
Presence of chemical leachates in some materials used for
bank stabilization.
Fish habitat
Changes in magnitude and distribution of current velocities.
Changes in amount and type of cover (brush, snags,
subaqueous vegetation, and irregularities in the bed and
banks). Diversity may be increased or decreased. Evaluating
the impact may be difficult because the habitat needs of a
species varies with the age of the fish and the season of the
year.
Changes in channel depth. Revetments often result in a deeper
and narrower channel.
Changes in fish habitat indirectly affecting birds and mammals
which prey on fish.
Benthic habitat
Changes in substrate material affecting benthic
(bottom-dwelling) organisms. Natural bed and bank material
(including brush, snags, and subaqueous vegetation) will be
replaced by materials used in the stabilization work. This may
be detrimental to some benthic species which are critical to the
food chain.
An extreme example of river stabilization work impacting aquatic habitat is provided
by some reaches of the Missouri River. The elimination of aquatic habitat as a result of
sediment accretions behind indirect stabilization works has been documented by Funk and
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