The invention provides a control gate (10) adapted to be installed across a channel (12) for liquids. Control gate (10) has a barrier member (22) that is pivotally mounted at or adjacent the base (20) of flow channel (12) and at least one side member (26) attached to barrier member (22). A drive means (34) co-operates with the at least one side member (26) or central member to allow raising and lowering of barrier member (22) to regulate flow of liquid through control gate (10). Also described is a method of measuring flow rate through a control gate.