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 CHAPTER 13
CLOSING
Streambank erosion causes great economic loss, loss of cultural resources,
degradation of water quality, aquatic and riparian habitat, and numerous downstream
problems. For example, wetlands are frequently ephemeral features in the natural landscape,
which through geomorphic process will eventually fill and become drier. Accelerated
streambank erosion in the basin upstream of a wetland decreases the biological productivity
of the wetland and reduces the life of the wetland. Another example that is frequently
experienced is the loss of flood control capacity due to sedimentation, which is caused by
accelerated streambank erosion upstream.
Streambank erosion is recognized by the Environmental Protection Agency (EPA) as
a major source of nonpoint pollution. The Water Quality Act of 1987, section 101, includes
the following policy statement: It is the national policy that programs for the control of
nonpoint sources of pollution be developed and implemented in an expeditious manner.
Unfortunately, at this point, no nationally recognized set of design and performance criteria
exist to meet this mandate, nor is there a comprehensive manual that provides guidance for
the design and construction of the many different types of streambank protection measures.
This handbook has been developed as a reference to be used in stabilization training
courses to be taught by the Waterways Experiment Station (WES) in cooperation with the
EPA. The topics presented in this handbook are:
C Fundamentals of fluvial geomorphology and channel process;
C Geomorphic assessment and analysis of the proposed project site and watershed
system;
C General approach and principles of bank stabilization;
C Selection of site specific stabilization techniques to include surface armor, indirect
methods, and bioengineered methods;
C Design and techniques for implementing grade control for system stabilization;
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