The Process
2.1.5
MONITORING
Monitoring of stream rehabilitation measures is essential for establishing requirements for
maintenance and repair of features, for establishing performance of the measures, and for providing an
essential feedback loop to planning and design of future projects. For example, if habitat enhancement is
a goal of the project, sampling of the biota is the only true measure of success. In addition, constructed
features should be monitored to determine if the features are performing as expected. Major watershed
and stream rehabilitation projects may require several years to construct, and monitoring of the earlier
constructed portions of the project can be directly related to improvements in the later portions of the
project.
2.2
THE ANALYSIS PROCESS
The analysis process, as shown in Figure 2.2, requires project goals to be defined prior to the
process. Three key elements in the analysis process are:
a. to evaluate the potential alternatives that may satisfy project goals;
b. to implement a systems approach that encourages the development of a thorough
understanding of the watershed physical processes; and
c. to develop a preliminary design that satisfies project goals.
2.2.1
GOALS
The goals developed for the project in planning dictate the progress of the rehabilitation design and
the alternatives which need to be evaluated to achieve the selected goals. Goals that may be selected
include reduction in downstream sediment delivery, channel stabilization to reduce erosion and to provide
better riparian habitat, flood control, or others.
2.2.2
EVALUATION OF POTENTIAL ALTERNATIVES
To satisfy project goals, alternatives should be considered early in the process. These alternatives
may include structural designs to mitigate erosion or enhance stability, changes in operational methods along
the stream, or land use. For example, alternatives to provide flood control usually can be described as
convey, control, or confine, i.e., include improved flood conveyance by increase channel size or slope,
control of flood discharge by reservoirs upstream or land use change, or confining the flood by using levees.
Chapter 3 discusses the geomorphic and engineering principles that should be considered in evaluating
alternatives.
Chapter 4 of this manual presents a summary of channel modification activities which generally
include the effects of the above described conditions. These activities fall under the general project
categories of flood control, drainage, navigation, sediment control, infrastructure protection, channel bank
stability, and flow control. Channel modification activities such as channel
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