Abstract: An application for a flow control system includes a tapered plunger situated within an conduit. The conduit is open to a downstream drainage system. The tapered plunger is buoyant, assisted by one or more floats attached such that, when the water level around the flow control system increases to a pre-determined level above a top rim of the conduit, the tapered plunger lifts due to the buoyancy. In such, the flow rate is maintained substantially constant. At the emergency level, alternate drain systems provide increased drainage to reduce the potential of flooding.

Abstract: An application for a flow control system includes a movable plunger held within a stationary riser, the stationary riser being in fluid communication with a drainage system. The movable plunger is buoyant, assisted by one or more attached floats such that, when the liquid level around the flow control system increases to a pre-determined level, the movable plunger lifts due to the buoyancy, thereby maintaining the pre-determined distance between the surface level and a bottom surface of the movable plunger, keeping the flow rate at an approximately constant level independent of the water level.