Silt excluder is provided
- AIn the canal on the downstream of the head regulator
- BIn the river on the downstream of the weir
- CIn the river adjacent to the head regulatorCorrect
- DIn the river far off from the weir on the upstream side
Solution
Concept
Location and placement of silt excluder
Formula
NONE
Step-by-step solution
1. Silt excluders are hydraulic structures designed to remove silt from water before it enters the canal system. 2. They are constructed in the river bed upstream of the canal head regulator, directly adjacent to it. 3. Silt ejectors, in contrast, are located inside the canal downstream of the head regulator. Answer: C
Explanation
A silt excluder is a structure constructed in the river bed just upstream and adjacent to the canal head regulator. It strips the silt-laden bottom layers of river water and disposes of them through under-sluices before the clearer surface water enters the canal.
Why the other options are wrong
A) Silt ejectors or extractors are provided in the canal downstream of the head regulator. B) Placing a silt excluder downstream of the weir does not prevent silt from entering the canal. D) Silt excluders must be positioned adjacent to the canal head regulator to exclude silt prior to canal entry.
Shortcut
Silt Excluder = River side (before canal); Silt Ejector = Canal side (after head regulator).
Common mistake
Confusing a silt excluder located in the river bed with a silt ejector located inside the canal.
Correct answer: C) In the river adjacent to the head regulator