How is river training for depth accomplished in practice_______________?
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Answer: D. groynes and bandalling
Explanation
Groynes direct water flow away from banks and towards the central channel to deepen the riverbed. Bandalling uses temporary screens to constrict the flow area and increase local velocity for scouring. Combining both structures provides effective river training specifically targeted at improving channel depth. River training structures manage flow velocities and sediment transport to maintain safe navigational depths. Groynes project outward from the riverbank into the main current to alter flow patterns. Bandalling is a traditional low-cost method widely used in alluvial rivers to induce local bed scour.
Maintaining adequate river depth is crucial for commercial navigation and preventing vessel groundings. Port authorities rely on these techniques to keep shipping channels open during seasonal low flow periods. Effective depth training reduces costly maintenance dredging operations in major river networks. Options a and b mention individual methods but fail to encompass the full range of effective depth training. Levees primarily provide flood protection rather than actively training the river for increased flow depth. Relying solely on groynes without bandalling is often insufficient for comprehensive depth management in shallow rivers.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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