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Remedial measures for sediment deposition in RoR

Short answer

Deposition is controlled by placing intake on outer bend with sill above bed, using an undersluice/flushing gate, a divide wall to skim cleaner water, gravel trap and settling basin with flushing. Also shut intake during flood peaks, lower pond for drawdown flushing, catchment treatment, and regular dredging.

Explain various remedial measures that help to control the deposition of sediments in a RoR project.

Sediment deposition in a RoR project occurs at the intake, in the gravel trap, in the settling basin, in the headrace and in front of the weir. It is controlled by the following measures.

  1. Choice of the intake location: place the intake on the outer bank of a river bend with the sill above the river bed, so that the bed load moves past it.
  2. Undersluice (scouring sluice) and flushing gates in front of the intake, which are opened during floods to flush the deposited sediment past the weir.
  3. Divide wall and curtain (skimming) wall to draw only the upper, cleaner layer of water into the intake.
  4. Gravel trap after the intake to settle the coarse material, with a flushing gate.
  5. Settling basin (desander) large enough to settle particles above the design size (0.15-0.2 mm), with a flushing system (intermittent or continuous).
  6. Flood operation rule: shut the intake during the high sediment load of the flood season, or when the concentration exceeds the limit.
  7. Weir pond operation: lower the pond level for sluicing during floods (drawdown flushing) so that the sediment is pushed out.
  8. Catchment treatment (afforestation, check dams, terracing, bank protection) to reduce sediment production.
  9. Regular maintenance: dredging and cleaning of the canal and the pond.

✓ Answer checked by Claude Opus 5.5 (high effort)

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