Constructed wetlands bave the capability to treat industrial wastewater containing a wide range of chemicals, including priority pollutants such as phenols and cresols, by processes such as absorption and bacterial breakdown, chemical oxidation, adsorption onto the bed matrix and sedimentation. A brief overview of this technique is presented along with details of preliminary trials carried out on textile dyeing and processing water.

The trials were conducted in a horizontal flow, gravel bed reed (30m × 5m), located in Melbourne, Australia. The textile dye wastewater was applied at an influent rate of 10 1/min., resulting in a retention time in the reed beds of 3–4 days, results indicated that breakdown of the visible dye occurred mainly in the first one third of the bed.