SUBSURFACE FLOW (SF) CONSTRUCTED WETLAND

A type of constructed wetland, a man-made marsh-like area used to treat wastewater. In the wetland, the effluent flows through a bed of rock or gravel, with the water level remaining below the surface of the gravel bed. Among the advantages of this type of system are its lack of odors, low potential for insect breeding, and minimal risk of public exposure and contact with the water in the system. Contrast with Free Water Surface (FWS) Constructed Wetland in which the water is exposed to the air. Also see Wetlands, Benefits.