Questions and answers about the Australian Drinking Water Guidelines (the Guidelines).

Questions and answers for updates to the Guidelines are also available, including the:

General advice about the Guidelines

1. What are the Australian Drinking Water Guidelines?

The Australian Drinking Water Guidelines provide a basis for determining the quality of water to be supplied to consumers in all parts of Australia. They are intended to provide a framework for the good management of drinking water supplies that if implemented will assure safety at the point of use. The Guidelines are not mandatory legally enforceable standards, and the implementation of the guidelines is at the discretion of each state and territory. The Guidelines are used by state and territory health departments and drinking water regulators, local health authorities and water utilities.

The Guidelines undergo a rolling revision to ensure they represent the latest scientific evidence on good quality drinking water. As sections of the Guidelines are revised, the Table of updates will be updated to provide the latest information.

For specific information on how these Guidelines are implemented in the states and territories, please contact the relevant drinking water regulator or health department.

2. How are the Guidelines updated?

NHMRC has designed a streamlined methodological framework to guide the rolling revision of chemical fact sheets in the Australian Drinking Water Guidelines. The methodological framework ensures consistency and alignment with the 2016 NHMRC Standards for Guidelines and international best practice, whilst making efficient use of limited project resources and time.

The methodological framework outlines a staged approach involving a transparent adopt/adapt process for evaluating existing health advice (such as recent international health-based guideline values) in the first instance instead of undertaking a full review of primary studies. This is to reduce duplication of effort, and the time needed to review the fact sheets, as many recent reviews undertaken by overseas agencies are available.

Existing guidance for a chemical may not always be available or appropriate to use for the Australian context. In these cases, a full review of recent primary studies is required, and additional resources will be needed to undertake the review.

3. Who will use the Guidelines?

The Guidelines are used by all agencies involved in the supply of drinking water, for example state and territory health departments and drinking water regulators, local health authorities and water utilities.

4. What is a health-based guideline value for drinking water?

Health-based guideline values indicate the amount of a chemical in drinking water that a person can consume on a daily basis over a lifetime without any appreciable risk to health. The Guidelines are protective of human health and take into account Australia’s conditions and context. The health-based guideline values are very conservative, and include a range of uncertainty factors, which always err on the side of caution.

See Chapter 6 of the Guidelines for further information on how guideline values are calculated.

5. What is an aesthetic-based guideline value for drinking water?

Aesthetic-based guideline values represent the concentration or measure of a water quality characteristic that is associated with consumer acceptability of drinking water. These guideline values are set to ensure drinking water is aesthetically pleasing, with the appearance, taste and odour of the water considered.

As the setting of an aesthetic-based guideline value may depend on public expectations, values can be determined by water authorities in consultation with consumers, considering the costs and benefits of further treatment of the water.

See Chapter 1.3 of the Guidelines for further information on water quality characteristics.

6. Are NHMRC advice and guideline recommendations mandatory?

No, but states and territories may reference or adopt them in their relevant legislation.

The role of NHMRC, as set out in Section 7 of the National Health and Medical Research Council Act 1992, is to inquire into, issue guidelines on, and advise on public health matters.

The Australian Drinking Water Guidelines provide an authoritative reference of what constitutes safe drinking water at the point of human consumption and are underpinned by a risk management framework that encourages site-specific planning for monitoring and treatment based on local conditions.

The Guidelines are adopted or referenced by various levels of government to develop policy, and these government departments have the responsibility to implement and monitor these policies. Management of drinking water depends on the legislated arrangements for water supply within each jurisdiction. For example, in some states, water supply is managed by the one water corporation, whereas in other states it is managed locally by numerous water suppliers. The relevant state or territory health and/or drinking water regulator, is responsible for regulating supply and establishing monitoring requirements.