CONSTRUCTION OF STABILIZATION WORKS
There are two fundamental differences between the construction of bank stabilization
works and that of more conventional structures. The first difference occurs simply because
part of the work is often out of sight (underwater). The second difference concerns site
conditions. These affect the design, performance, and even the appropriateness of the
technique being used. Often conditions change dramatically between design and construction.
These changes may be caused by unusually high flows, or may be due to normal stream
dynamics. Environmental sensitivity to construction operations may change with the season
of the year, since nesting, spawning, and other wildlife activities are all seasonal. Also, the
timing of construction affects the success of establishing vegetation. To complicate matters
further, the construction operation itself may initiate changes in site conditions. Such changes
not only require the attention of the designer, they often pose problems for construction
personnel and contract administrators.
Specialized aspects of the construction of bank stabilization works are sparsely
documented, perhaps because construction personnel tend to focus more on performing work
than on academic reporting. This is in contrast to the practice of engineers and scientists,
who are usually encouraged, or even required, to document their research findings and
It would be inappropriate for this text to attempt to deal with construction in terms
of the details of plant, labor, materials, administration, and management. These aspects of
construction are to a large degree dependent upon organizational policy, local custom and
workforce capability, and the stabilization technique being employed. Therefore, this
discussion will concentrate on concepts and ideas which are peculiar to river stabilization
work, and which are not widely documented. These aspects are easily overlooked by the
designer when other matters are clamoring for attention, but they should be integrated into
the planning and execution of construction in order to obtain the most effective,
environmentally sound, and economical project.
Some detailed factors which relate to construction of specific types of bank
stabilization, but which are more pertinent to the selection and design process, have been
discussed in Chapters 5 and 6.