Patent ID: 8889006

Claim:
A system for wastewater treatment using aquatic plants in a wastewater environment having an inlet, an outlet and a treatment zone extending between the inlet and outlet, wastewater being disposed in the treatment zone and flowing into the treatment zone from the inlet and out of the treatment zone from the outlet, the system comprising: an outlet barrier structure for controlling a flow of wastewater from a treatment zone to an outlet from the wastewater environment, the outlet barrier structure comprising: a base having a lower portion disposed on a bottom of the wastewater environment adjacent the outlet and an guide portion extending upwardly therefrom, the base having a negative buoyancy; an upper portion movably engaging the guide portion of the base, the upper portion having a top edge, the upper portion having an adjustable buoyancy such a position of the upper portion relative to an upper surface of the wastewater at the outlet may be adjusted by adjusting the buoyancy of the upper portion; a first immersed support structure with adjustable buoyancy for supporting aquatic plants in the wastewater environment, the first support structure disposed in the wastewater in the treatment zone, the first support structure comprising: a support frame; a plurality of plant holders each having a plant receiving area, the plant holders being interconnected with the support frame such that some of the plant holders are disposed at a first vertical position and others of the plant holders are disposed at a second vertical position; wherein the support structure has adjustable buoyancy such that a position of the support structure relative to the upper surface of the wastewater in the treatment zone may be adjusted by adjusting the buoyancy of the support structure, whereby some of the plant holders are positioned at a first depth and others of the plant holders are disposed at a second depth with respect to the upper surface of the wastewater.