CHAPTER 6
SELECTION AND DESIGN OF CHANNEL
REHABILITATION METHODS
This chapter addresses the selection and design of channel rehabilitation methods. The types of
improvement measures adopted in a rehabilitation project depend upon the goals of the project and the
physical characteristics of the watershed. The three principle techniques discussed in this chapter are grade
control, bank stabilization, and flow control. Bank stabilization and grade control are the primary methods
employed in channel rehabilitation projects to control erosion and sedimentation. Because channel
rehabilitation projects often occur in urbanized areas where flow control has been implemented, it is
important to integrate the morphologic impacts of these features into the channel rehabilitation plan. For
this reason, a discussion of the morphologic response to flow control is presented in this chapter.
6.1
STREAMBANK STABILIZATION
Although there are many different types of bank stabilization measures, they can generally be
classified as armor protection, indirect protection, or vegetation. General descriptions, advantages,
disadvantages, and typical applications are presented in this chapter. For a more detailed treatment of
streambank stabilization, the reader is referred to Biedenharn et al. (1997).
The suitability and effectiveness of a given bank stabilization technique are a function of the
inherent properties of that technique, and in the physical characteristics of the proposed worksite.
Consequently, there is no single stabilization technique that is applicable to all situations. Unfortunately,
many practitioners often attempt to force a particular technique that they are familiar with into all situations.
For instance, there are some engineers and scientist that believe that bioengineering techniques are the
answer to all erosion problems. Likewise, there are those who will recommend a complete riprap armor
for the bank when another, less costly, and perhaps more environmentally acceptable technique would be
just as effective.
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