Automatic water sluice gate is under the waterpower and action of gravity, in the given water height condition; and it start and stop automatically as the flux change.

水力自控闸门是借助水力和重力作用，在一定的水位条件下，随流量的变化，自动启闭的自动化闸门。

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They regulate the flow of water by the sluice gate.

他们用水闸门控制水的流量。

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As soon as the sluice gate was opened, the water surged in.

水闸门一开，水便一下子涌了出来。

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People living near Portavoe Reservoir outside Donaghadee have claimed that water levels have dropped recently after a sluice gate was left open.

BBC: dead fish