Drinking-water Standards for New Zealand 2005 (Revised 2018).

The availability of potable drinking-water for all New Zealanders is a fundamental requirement for public health. There are six well-established principles for potable drinking water: 1. A high standard of care must be embraced; 2. Protection of source water is of paramount importance; 3. Maintain multiple barriers against contamination; 4. Change precedes contamination; 5. Suppliers must own the safety of drinking water; 6. Apply a preventive risk management approach. The Health Act 1956 protects the health and safety of people and communities by promoting adequate supplies of potable and wholesome drinking water from all drinking-water supplies. It provides for the Minister to issue or adopt drinking-water standards; and imposes a range of duties on drinking-water suppliers, including duties to monitor drinking water; and take all practicable steps to comply with the Drinking-Water Standards for New Zealand (DWSNZ).
The two themes of the DWSNZ are: 1. maximum acceptable values (MAVs) or water quality standards, which define the quality specifications for all drinking-water; 2. compliance criteria, which specify monitoring requirements and remedial actions to be followed when a transgression of a MAV occurs. The DWSNZ are applicable to networked drinking-water supplies, as defined in the Health Act 1956. The DWSNZ do not set out how a water supply should be managed. The Health Act covers the high-level obligations of a water supplier, and the Local Government Act 2002 covers broader management obligations. Those obligations specific to risks are covered by a supplier’s water safety plan. The DWSNZ do not set quality standards for water used for industrial or agricultural purposes. Bottled water is subject to the Food Act 2014. For people with certain medical conditions, or for uses of water for purposes other than drinking, additional or other water quality criteria may apply.