What is Weir & Barrage ?

Weir :- If the major part or the entire ponding of water is achieved by raised crest and a smaller part or nil part of it is achieved by the shutters, then this barrier is known as weir.
Barrage :- If most of the ponding is done by gates and a smaller or nil part of it is done by the raised crest, then the barrier is know as barrage.

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