|1.||See also sluicegate head gate, Also called: water gate a gate in a sluice that is used to control the flow of water|
|2.||(often plural) a control or barrier against an outpouring or flow: to open the floodgates to immigration|
gate for shutting out or releasing the flow of water over spillways, in connection with the operation of a dam. Vertical lift, or radial, gates rise to permit flow under the gate but over the spillway crest. Drum gates rotate backward, lowering their tops and permitting a measured flow over the top of the gate. Drum gates present the fewest problems in the passage of ice or drift over the spillway.
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