General Approach to Bank Stabilization
4.1.4 RELOCATION OF ENDANGERED FACILITY OR STREAM CHANNEL
These alternatives may require the smallest initial expenditure to "solve," or at least
postpone, bank stability problems. They usually have little else to recommend them.
4.1.4.1 Relocation of Endangered Facility
This approach may be dictated by public policy or private preference if it is the least
costly alternative. It obviously has no impact on stream characteristics, which can be a
positive or a negative factor, depending upon the particular circumstances. It would be most
likely to be a positive factor in environmentally sensitive areas where construction of works
in the stream channel is to be avoided if possible. The relocation of a structure to a place of
safety requires an accurate prediction of the rate and direction of channel migration.
Factors which affect the feasibility of structure relocation are:
Cost;
Degree of safety required to be provided by relocation; and
Social and political impacts of relocation.
4.1.4.2 Relocation of Stream Channel
Factors which affect the feasibility of stream channel relocation are:
Cost ;
Potential for induced damages;
Stream regime; and
Potential environmental benefits of the abandoned channel.
Channel relocation does not always induce instability upstream or downstream, but
adjacent landowners are likely to believe otherwise, and legal actions may result. Stream
regime and local site conditions determine whether relocation of the channel will cause serious
problems. Stabilization of the relocated channel itself may be necessary to avoid problems
caused by it migrating after it is constructed. Environmental benefits may result from the
formation of a new and abandoned channel, but such benefits are often difficult to maintain
permanently unless the sediment load of the stream is relatively small.
8
78
Previous Page
