Figure 5. Schematic layout of a constructed wetland with horizontal subsurface flow.
1 inflow distribution zone filled with large stones; 2 impermeable layer; 3 filtration
material; 4 vegetation; 5 water level in the bed; 6 outflow collection zone; 7 drainage pipe;
8 outflow structure with water level adjustment [44]. With permission from
Backhuys Publishers.