Use of Aquatic Macrophytes for Wastewater Treatment

Wastewater treatment systems using water hyacinths have the capability of producing secondary or advanced secondary effluents. Hyacinths also have the potential for producing effluents meeting advanced waste treatment standards if optimum plant harvesting techniques and supplemental methods for additional phosphorous removal are developed. Widespread use of hyacinth systems will be confined to relatively warm climates because growth ceases at water temperatures below 50°F (10°C). Treatment facilities using duckweed could be used in colder climates, however, systems using this plant are in a very preliminary stage of development. In addition to the removal of conventional pollutants, aquatic macrophytes systems also have the capability of biologically concentrating heavy metals and synthetic organic chemicals. Preliminary cost analyses indicate water hyacinth systems could be more economical than comparable land or conventional treatment techniques.