Model Guidelines for Domestic Greywater Reuse for Australia
This report was produced for the Urban Water Research Association of Australia, a now discontinued research program.
Report no. UWRAA 107
This report is the third in a three part research project. Its purpose is to achieve the project’s final goal of formulating model guidelines for the regulation of greywater re-use systems in Australia; that is, those systems which re-use domestic greywater from sewered premises. Domestic greywater is defined as that which is derived from a non-industrial source.
The first part, “Domestic Greywater Re-use: The Preliminary Evaluation (UWRAA Research Report No 60, 1993)”, was completed in 1993. It included:
· Overseas correspondence
· a literature search
· chemical and microbial analysis of some sullage systems
The report concluded that:
· the western states of the USA and Japan are the world leaders in this type of onsite re-use
· greywater re-use poses environmental and health concerns but, with adequate guidelines, could achieve substantial water savings.
The second part, “Domestic Greywater Re-use: Overseas Practice and its Applicability to Australia (UWRAA Research Report No 73, March 1994)”,was completed in 1994. This report investigated overseas practices in greywater re-use and how this could be applied to Australia.
It is intended that this report, “Domestic Greywater Re-use: Model Guidelines”, will assist Australian water and regulating authorities in meeting the challenge to fully utilise this valuable resource without:
· Compromising public health,
· causing detrimental impact tothe environment or
· down grading the livability ofour residential areas.
The report covers:
· Surface Reuse
· Sub-surface reuse
· Storage of greywater
· Chemical content
· Hand Basin Toilets
· Toilet Flushing
The report proposes modelguidelines should the re-use of domestic greywater become legal.
However, caution must beexercised when introducing greywater re-use because of the undefined increasein risk to public health and the environment.
We live in a society that has arelatively healthy population with little natural resistance to most water,mosquito and vermin borne diseases. The sanitary sewer has been one of thefundamental measures which has improved health in the developed world and anychange from the current status must be such as not to compromise the gains inpopulation health which have been achieved.
Infectious disease epidemics can occur once disease is introduced to the non-resistant population and has a mode of transmission. Any decision to change the present sanitary practices needs to be seriously considered .