General Approach to Bank Stabilization
in flow or channel characteristics. Bank stability can then be addressed as an integral part of
that evaluation.
4.1.1 RIVER BASIN MANAGEMENT
This approach is feasible only in comprehensive projects. A large part of the basin
must be controlled or managed to be effective in stabilizing the downvalley streams.
Significant local cooperation, social and economic constraints, and legal safeguards are
involved, and if measures that are comprehensive enough to significantly reduce channel
instability are implemented, the project may have complex effects on other aspects of long-
term stream behavior.
The operational aspects and effectiveness of basin management depends on basin
characteristics such as topography, land use, climate, soil types, vegetation, and rainfall
patterns. The two major components of basin management are land treatment and reservoirs.
4.1.1.1 Land Treatment
Major components of land treatment are:
Riparian greenbelts
Agricultural practices to minimize runoff and erosion
No-till planting
Crop rotation
Contour plowing and terracing
Improved management of irrigation flows
Improved forestry practices
Limits on clear-cutting
Careful collecting and hauling practices
Improved grazing practices
Stable runoff channels
Benefits of land treatment to channel stabilization are as follows:
Peak discharges are reduced somewhat, thus reducing streamflow
attack on the banks, as well as perhaps providing some flood control
benefits.
Sediment supply to the stream system is also reduced, which results
in a reduction in channel aggradation and associated flood problems,
as discussed by Liu (1989) for the Yellow River, and an improvement
in water quality and navigation depths downstream. The precise
effects depend on the character of the sediment supply and other basin
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