The Use of Vetiver Grass Wetland for Sewerage Treatment in Australia. Third International Vetiver Conference

sewerage effluent at Toogoolawah in South East Queensland. The sewerage treatment plant is situated on a 22-ha site on the northern edge of town. The aim of this scheme was to improve water quality before the effluent discharges to the natural wetlands. The biggest problem with the quality of the effluent is its high nutrient loading. With the recent changes to license conditions imposed by the Environmental Protection Agency, the existing treatment plant no longer complies with the license and an upgrade of the plant was required. Instead of traditional upgrades, a new and innovative phyto-remedial technology recently developed in Queensland by the Department of Natural Resources and Mines, is being implemented at Toogoolawah. Under the Vetiver Wetlands System, the effluent is being treated in two stages: • Preliminary treatment of the pond effluent in situ by floating pontoons placed in the ponds, and by vetiver planting around the edges of the three sewerage ponds. • Main treatment by vetiver wetlands, once the effluent exits the sewerage ponds it passes through a Vetiver Grass contoured wetlands constructed over 3 hectares of the land. The Vetiver Grass wetlands have been constructed in rows following the contours to allow good contact between the grass and the effluent. The Vetiver Grass takes up the water and i