What Are Constructed Floating Wetlands?
Constructed Floating Wetlands (CFWs) are an innovative water treatment device that uses biomimicry to remove pollution from water. CFWs function like hydroponic systems, where the plant roots grow down into the water to access nutrients. The exposed plant roots create an effective filter for suspended solids and also provide a very large surface area for growth of microbial biofilm.
Besides exceptional water treatment performance, CFWs can also:
Reduce algae growth
Provide habitat for a variety of animals, birds and fish
Provide a food source for microorganisms, fish and other aquatic biota
Enhance visual amenity of water bodies
Reduce water temperatures under FTW modules
Inhibit wind and wave energy, protecting shorelines, riverbanks and other vulnerable areas from erosion
Constructed Floating Wetland Schematic
How do floating wetlands work?
The two main treatment pathways for CFWs are the plants and the microbial biofilms that grow on the plant roots. The plants serve to uptake and sequester excess nutrients, like Nitrogen and Phosphorus, which can be removed from the system as part of a routine harvesting program. This not only benefits a range of plant species, it is also one of the few efficient ways to permanently remove phosphorus loads from a waterbody. The plant roots provide a massive surface area for biofilm growth. The root surface area is far greater than traditional treatment systems, so CFWs are able to provide enhanced treatment in a smaller footprint. This drives down both capital and operational expenditure.
CFWs can be anchored in a variety of ways and each job has a custom, certified design to suit. A properly designed CFW treatment system will maximise contact with polluted water, ensure the system can fluctuate with water levels during dry and wet periods.