1 GREYWATER REUSE: METHODS AND DIRECTION FOR POSSIBLE FUTURE DEVELOPMENTS IN AUSTRALIA.

Wastewater is often considered to be a source of public health problem and to be disposed of rather than considered as a resource. The choice of treatment system is usually governed by disposal strategy rather than reuse options. Domestic sewage generally consists of wastewater produced from the toilet, kitchen sink, bath, shower, washbasin and laundry. Toilet waste, which makes up 25 to 30 percent of the flow, is referred to as black water, while the rest of the wastewater is referred to as greywater. The blackwater contains the major portion of biochemical oxygen demand, suspended solids, bacteria and nutrients. So if the black water is treated separately then the treatment of greywater alone becomes easier and less complicated. Greywater reuse is widely supported by the community in Australia and promoted by researchers. However regulatory authorities have not given permission for greywater reuse. This paper illustrates a few case studies of greywater reuse trials following treatment of the greywater. The reasons for greywater reuse to be permitted by the regulatory authorities are articulated. In the future greywater reuse should be encouraged, and excess payment may be imposed if the greywater is to be treated by a municipality. This paper discusses the different treatment processes being developed to treat greywater successfully. Development of these methods and successful completion of the trials are necessary to develop public confidence to encourage greywater reuse. Present status of the methods and practices with direction for possible future developments are discussed in the paper