Is risk associated with drinking water in Australia of significant concern to justify mandatory regulation?

Presently in Australia there are no mandatory drinking water standards. Here we argue that the risk associated with drinking water in Australia is of a dimension discernible to warrant mandatory regulations. The catchments that supply the major metropolitan areas of Sydney and Adelaide, and the groundwater for the city of Perth have been seriously compromised by the encroachment of development and activities. Melbourne in the past has generally relied on a closed catchment reservoir system; however, population growth in the near future will sequester the full online operation of additional reservoirs, which have multiple land use catchments. In addition to the current landscape circumstances, the management of a water system in itself proposes significant issues of risk. Two critical assumptions that are unique to a mass medium substance like water and dramatically alter the appraisal of risk are: (1) very large numbers of people are potentially exposed, and (2) small changes in contaminant levels may have adverse population outcomes. It is also known that water reticulation systems frequently suffer from contamination problems caused solely by the distribution system, and optimal management of these facilities would best be served by statutory protected transparency and dedicated water quality programs. In 1979, an Australian parliamentary committee stated that an "uncontaminated water supply is" a "basic requirement for the obtainment of good health"; however, recent surveys of Australian water systems show many are not meeting basic water quality criteria, and many communities are not receiving regular monitoring or testing as required by government authorized Australian drinking water guidelines. Exacerbating this situation is the lack of reporting and statutory endorsed standardized procedures to ensure information is properly and promptly recorded and that data are centralized for maximum benefit. The evaluation of risk associated with drinking water in Australia is often hampered by inadequate or incomplete data. Lastly, regional and rural water supplies face a vast array of contemporary problems and experiences that include widespread usage of pesticides and agricultural chemicals. In recent years, the Darling River has experienced the worst algal bloom known to man, and this river system not only supplies a number of regional and rural towns with water, but eventually connects with the River Murray, which supplies the State of South Australia with approximately 50% of its water requirements.