This protocol is derived from the Australian Drinking Water Guidelines (the Guidelines) to be used by Public Health Units (PHU) and water utilities to guide their joint response following the detection of physical and chemical water characteristics that exceed the Guidelines.
Under Section 22 of the Public Health Act 2010, the Chief Health Officer has the power to issue advice, for the benefit of the public, concerning the safety of available drinking water and any possible risks to health involved in the consumption of that water. This may include a recommendation for the provision of an alternative supply of water or a “do not drink” advice. These powers are delegated to Public Health Unit Directors. A supplier of drinking water must issue to the public the advice provided under the Public Health Act, if so directed.
Australian Drinking Water Guidelines
have set aesthetic and health related guideline values for physical and chemical characteristics. Aesthetic guideline values are set at the concentration that ensures water is aesthetically pleasing in terms of taste and odour, and can be used without causing corrosion of plumbing or staining. Health-related guideline values are set at the concentration that, based on current knowledge, does not result in any significant risk to the health of the consumer over a lifetime of consumption.
Further information on the physical and chemical quality of drinking water is available in the
Guidelines (Chapters 6 and 10). Where both aesthetic and health-related guideline values are exceeded, consider health related characteristics first and then aesthetic characteristics.
The water utility is responsible for carrying out all necessary investigation and resampling as specified in this response protocol.
The Water Utility, PHU, and NOW regional inspector should consider the following when conducting the risk assessment:
Further information on conducting health risk assessments is available in Section 3.2.3 of the
Australian Drinking Water Guidelines and via
enHealth's list of environmental health publications.
The PHU, Water Unit and/or Chief Health Officer will consider the following when determining the need for public notification, a do not drink advice, or an alternative supply:
Also see the
flowchart from the
NSW Drinking Water Monitoring Program booklet.