Under-sluices incorporated into a weir at the upstream floor level to clear deposited sediments downstream are termed ______________________?
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Answer: C. Scouring sluices
Explanation
Scouring sluices are gate-controlled openings located in weirs to flush out accumulated sediment downstream. Opening these gates creates high-velocity flushing currents that scour away silt deposited near the canal head. Maintaining deep channels in front of head regulators ensures clean water enters the off-taking canals. Weirs built across sediment-laden rivers inevitably trap significant sand and silt deposits behind their crests. Under-sluice bays are situated at the lowest riverbed level to facilitate efficient sediment removal operations. Operators open these sluice gates periodically during flood seasons to scour accumulated bed material downstream.
These flushing mechanisms are vital for the long-term operational health of river diversion headworks. It matters because allowing sediment to accumulate blocks canal intakes and reduces regional irrigation efficiency. Hydraulic engineers carefully position scouring sluices to align with main river flow lines for maximum scour. Option B refers to regulators controlling water entry into canals rather than sediment-scouring sluices. Option A is a general structural term, whereas scouring sluices specifically denotes their sediment-clearing function. Option D is a broad category describing any gate on a structure rather than this specific scouring feature.
- Subject
- Agriculture
- Category
- Agriculture
- Topic
- —
- Difficulty
- medium
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