Drinking-water legislation

The Health Act 1956 was amended by the Health (Drinking-Water) Amendment Act in October 2007 and aims to protect public health by improving the quality of drinking-water provided to communities.

More information on the legislation is provided on this page:


The Act implements Cabinet’s decision in November 2000 to introduce a flexible, risk management based and outcome focused legislative framework for drinking-water (reticulated and tankered drinking-water).

The main duties in the Act only apply to supplies above a certain size, that is those that serve:

  • 25 or more people for 60 or more days per year; or
  • if there are fewer than 25 people, but 6000 or more ‘person/days’ (that is the number of people multiplied by the number of days they receive water from the supply).

These main duties which apply to suppliers above this certain size include the obligations to:

  • take all practicable steps to comply with the (previously voluntary) drinking-water Standards
  • introduce and implement water safety plans (formerly known as public health risk management plans) for the water supply (if serving more than 500 people);

Supplies that serve fewer people never have more than very minimal duties under the Act. They will need to apply to be included on the Register of Community Drinking-water Supplies, however, this is free and involves no other obligations.

The Act commences on 1 July 2008. From this date all drinking-water suppliers will be required to apply to the Ministry for registration on the drinking-water register.

The other duties come into force progressively as follows:

Compliance dates for suppliers under the legislation
Type of supplier Legislative compliance date as originally enacted New compliance dates as announced by the Government on 24 June 2009
New Drinking-Water Suppliers 1 July 2009 1 July 2012
Large Drinking-Water Suppliers 1 July 2009 1 July 2012
Medium Drinking-Water Suppliers 1 July 2010 1 July 2013
Minor Drinking-Water Suppliers 1 July 2011 1 July 2014
Small Drinking-Water Suppliers 1 July 2012 1 July 2015
Neighbourhood Drinking-Water Suppliers 1 July 2013 1 July 2016
Rural Agricultural Drinking-Water Supplies 1 July 2013 or later depending on when standards are amended to explicitly recognise this category of supply 1 July 2016

The Act makes special provision for supplies that provide water for both agricultural and drinking-water purposes, to ensure that they are not required to make fit for humans water that is only used by animals or crops. These supplies fit into the ‘rural agricultural drinking-water supply’ category. Supplies in this category face no duties under the drinking-water standards until 1 July 2013 at the earliest. The drinking-water standards will be amended to determine exactly how such supplies will be managed, and the Ministry is seeking opinions on how this should be done.

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The enactment of this legislation resulted from a concern that the organisation of New Zealand’s drinking-water supplies was not adequate to safeguard communities. New Zealand had been unusual among developed nations in relying almost entirely on voluntary mechanisms to safeguard the treatment and distribution of drinking-water. This represents a risk to public health in two main ways:

  • Higher rates of disease – New Zealand has relatively high rates of largely preventable enteric or gastro-intestinal disease. For example, the campylobacteriosis rate in NZ is twice that of England and three times that of Australia and Canada. This is at least partly attributable to contamination of drinking-water. Campylobacteriosis – which is just one of the potentially waterborne diseases in New Zealand – can involve fever, headache, abdominal pain, nausea, vomiting and as many as ten watery, often bloody, bowel movements daily. Symptoms may persist for up to a week and prolonged illness or relapses may occur in adults. The burden of disease is more of a problem for rural communities.
  • Higher risk of a major disease outbreak – The previous state of NZ’s drinking-water legislation gave little effective protection or deterrence against a major outbreak of disease caused by deliberate or accidental contamination of drinking-water supplies. Such events have occurred in overseas jurisdictions. For example Walkerton (pop 4000), Canada, where 7 deaths and 2321 reported cases resulted from E. coli in May 2000. Another example is Milwaukee (pop 583,000), Wisconsin, with 70–100 deaths and 400,000 people sick as a result of contracting cryptosporidiosis from the water supply in 1993.

To date New Zealand has been fortunate. Apart from the 3500 people who became sick in Queenstown in 1984 because of contaminated drinking-water, most outbreaks of drinking-water disease have tended to be on a small scale, involving less than a hundred cases – for example

  • 61 cases of campylobacteriosis at a school camp near Christchurch in 1997;
  • 67 cases of campylobacteriosis at Wainui in 1997;
  • 187 cases at a college in May 2001 – of which only two were originally reported to the Medical Officer of Health;
  • 69 cases of viral gastroenteritis at a major ski field in 1996; and
  • 49 cases at a school camp in the Waikato in 2003.
  • 213 known cases of acute gastroenteritis due to norovirus (and probably many more unreported) at Cardrona skifield in July 2006).

There was also contamination of the Masterton town water supply by Cryptosporidium during July and August 2003.

Estimation of the Burden of Water-borne Disease in New Zealand – Preliminary Report
A preliminary study of waterborne disease in New Zealand.

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The previous situation – A largely voluntary regime

Management of drinking-water in New Zealand forms a continuum that can be broken into three main parts.

  1. The environment – The source of the water, either from below ground or from surface catchments, is primarily governed by the Resource Management Act 1991.
  2. Water suppliers – This involves procuring the raw water from the environment, followed by storage, assessment, treatment, and distribution to consumer via a piped or tankered supply. This system was previously governed by a largely voluntary regime. The Act regulates this system of treatment and distribution, but reaches back to some degree to require some participation by the supplier in catchment management.
  3. Storage and distribution – Storage and distribution of water in tanks and pipes within buildings up to the point of use (generally a tap) is governed by the Building Act 2004. This Act takes over responsibility for water once it leaves a public networked supply and enters the building-owner’s property (usually at the water toby), and also applies to water distributed within a building from its own self-supply (eg, a roof tank or bore).

The system which governs the ‘second part’ of drinking-water management by water suppliers is administered by the Ministry of Health. Prior to the Act the system, was comprised of entirely voluntary elements:

  1. The New Zealand Drinking-Water Standards. These standards have been published since 1984. They provide the yardstick against which water quality is measured and detailed specifications for drinking-water suppliers, including maximum acceptable values for a range of contaminants and monitoring requirements. Compliance with the standards was previously voluntary. (Under the Act suppliers must take all reasonably practicable steps to comply with the standards).
  2. Register of Community Drinking-Water Supplies in New Zealand. The register of over 2000 supplies is maintained as part of the Water Information NZ (WINZ) database system for drinking-water. The register provides health professionals, drinking-water professionals and the general public with an authoritative summary of the health risk status of all community drinking-water supplies known to the Ministry. Inclusion on the register was previously voluntary. (It is now mandatory for all drinking-water supplies, and also self supplies which supply water to community purposes buildings, such as town halls, schools, hospitals, ski-fields etc).
  3. Public health grading of community drinking-water supplies. The principal driver of improvement in the quality of drinking-water in New Zealand since 1993 has been the public health grading of drinking-water supplies by public health unit staff in district health boards.
  4. Water Information New Zealand. The national electronic drinking-water information database.
  5. Public Health Risk Management Plans. Under the previous voluntary system the Ministry encouraged and promoted the risk-based management approach of drinking-water supplies through the adoption of Public Health Risk Management Plans. These are now known as water safety plans (The Act will require all supplies serving more than 500 people to develop and implement water safety plans. Supplies smaller than this are encouraged to prepare such plans).
  6. Annual Report on the Microbiological and Chemical Quality of Drinking-Water Supplies in New Zealand. The report, covering the previous year, is issued in November / December each year.
  7. Guidelines for Drinking-Water Quality Management in New Zealand. These technical Guidelines are a complement to the New Zealand Drinking-Water Standards.
  8. The use of Ministry-recognised laboratories. Only Ministry of Health-recognised laboratories may carry out testing and other procedures to demonstrate compliance with the Standards.

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The need for further improvements

In order to spearhead further improvements the Government announced a drinking-water assistance programme on 5 May 2005. It involves two components: (i) the Technical Assistance Programme (TAP) and; (ii) the Capital Assistance Programme (CAP). It has a $136.9 million budget (GST excl).

The TAP programme commenced on 1 July 2005 and aims to provide resources to assist drinking-water suppliers to prepare water safety plans for their supply. These plans will assess potential problems with a drinking-water supply and identify and manage risks associated with that supply.

The CAP programme started providing financial assistance for upgrades to water suppliers’ infrastructure on 1 July 2006. The Ministry sought submissions to help determine eligibility criteria for assistance. Public consultation meetings were held in June and July 2006. The assistance programme is complementary to the Bill, but is an independent programme. Though the assistance programme will ease compliance burdens for suppliers the Act is not predicated on the availability of such assistance.

The Act was required because the voluntary elements of the drinking-water strategy, while important, were not achieving the required improvement. The required improvements related to three main areas:

  1. Greater compliance with the Drinking-Water Standards – Although 71 percent of the New Zealand population is currently served by water supplies that comply with the standards, the remaining 29 percent are served by supplies either not compliant or not known to be compliant. These supplies are either reticulated supplies (16 percent) that are generally located in towns with less than 5000 people, or buildings with their own drinking-water supply (eg, roof or bore water) (13 percent). The potential for gain is greatest in the rural areas;
  2. Greater coverage on the Drinking-Water Register – The number of known supplies on the Ministry of Health drinking-water register as of June 2005 was 1953. There are an estimated 1000 further supplies that are not on the register. This is a good result for a voluntary system, but is not adequate if New Zealand’s drinking-water supplies are to be raised to acceptable levels;
  3. Proactive management of water supplies through water safety plans – Lessons learned in overseas jurisdictions tell us that effective water management needs to involve multiple interventions at many levels so that, if one part of the system fails, the others are ready to compensate for this failure and provide back up. New Zealand suppliers generally do not practice this type of management. Without such management the potential for mass disease outbreaks like those that occurred at Walkerton and Milwaukee is much higher.

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What does the Act do?

The Act does the following:

  1. Requires drinking-water suppliers to take all practicable steps to ensure they provide an adequate supply of drinking-water that complies with the New Zealand Drinking-Water Standards;
  2. Requires drinking-water suppliers to introduce and implement water safety plans;
  3. Ensures drinking-water suppliers take reasonable steps to contribute to the protection from contamination of sources from which they obtain drinking-water;
  4. Requires officers appointed by the Director-General of Health to act as assessors to determine compliance with the Act and to have their competence internationally accredited;
  5. Requires record keeping and publication of information about compliance;
  6. Provides for the appropriate management of drinking-water emergencies;
  7. Improves enforcement by providing an escalating series of penalties for non-compliance.

Register of Drinking-Water Assessors Appointed under the Health Act 1956


Section 69ZX of the Health Act 1956 (as amended by the Health (Drinking Water) Amendment Act 2007) requires the Director-General of Health to maintain a register of agencies that have been appointed as drinking water assessors. 

No agencies have been appointed as drinking water assessors, but a number of individuals have been appointed, which section 69ZK of the Act also provides for.  While not statutorily required, a register of individual drinking water assessors is being maintained.  This register includes the individual's name and employer and the date of their appointment as a drinking water assessor.

The term of appointment for each drinking water assessor is valid until either the drinking water assessor ceases his or her current employment or until it is revoked by notice in writing.

The Director-General of Health has authorised each Drinking Water Assessor to exercise only the following powers set out in the Health Act 1956:

  • the powers conferred in section 69ZP(1)(a) powers of entry;
  • the powers conferred in section 69ZP(1)(b) inspect and copy records;
  • the powers conferred in section 69ZP(1)(c) require information;
  • the powers conferred in section 69ZP(1)(d) supply information and documents;
  • the powers conferred in section 69ZP(1)(e) conduct inspections, surveys, tests;
  • the powers conferred in section 69ZP(1)(f) direct the supply to conduct tests;
  • the powers conferred in section 69ZP(1)(g) take samples;
  • the powers conferred in section 69ZP(1)(h) verify the competence of people performing tests if they are not done by a recognised laboratory;
  • the powers conferred in section 69ZP(1)(i) provide information to the Director-General of Health;
  • the powers conferred in section 69ZQ(1) taking assistants and equipment when exercising power of entry.


Drinking-Water Assessors

Name Date of Appointment as DWA Employer (District Health Board)
Tatiana Derevianko 28 July 2008 Auckland DHB
Sioeli Takataka 28 July 2009 Auckland DHB
Can Lin (Ken) Zhu  02 August 2010 Auckland DHB
Xiaoning (Shaun) Yu 24 September 2013 Auckland DHB
Shiwen Sun 16 September 2014 Auckland DHB
Leslie Breach 16 September 2014 Auckland DHB
Shanshan Li 11 January 2017 Auckland DHB
Grant King 17 October 2014 Bay of Plenty DHB
Braden Leonard 8 February 2018 Bay of Plenty DHB
Kirsty Macleod 28 July 2008 Canterbury DHB
Denise Tully 28 July 2008 Canterbury DHB
Judy Williamson 28 July 2008 Canterbury DHB
Helen Judith Graham 26 June 2013 Canterbury DHB
Fiona Humpheson 25 March 2017 Canterbury DHB
Hayley Proffit 25 March 2017 Canterbury DHB
Amelia Jones Haskell 28 May 2017 Canterbury DHB
Joanne Waldon 13 April 2015 Hawke's Bay DHB
Matt Molloy 26 February 2017 Hawke's Bay DHB
Reynold Ball 27 March 2018 Hawke's Bay DHB
Barbara Stevenson 3 August 2017 Hutt Valley DHB
Vanessa Young 15 October 2015 Hutt Valley DHB
Matt Parkinson 23 July 2018 Hutt Valley DHB
Peter Wood 31 July 2008 MidCentral DHB
Louise Allen 9 November 2016 MidCentral DHB 
Evan McKenzie 23 February 2008 Nelson Marlborough DHB
David Speedy 27 August 2008 Nelson Marlborough DHB
Matt Molloy 19 March 2015 Nelson Marlborough DHB
Zane Jones 27 August 2008 Northland DHB
Matt Molloy 3 September 2015 Northland DHB
Jeffery John Garnham 28 May 2017 Northland DHB
Rosemarie Nelson 08 February 2010 Southern DHB
Simon Ou 19 February 2009 Southern DHB
Michael Wong 08 February 2010 Southern DHB
Susan Moore 18 December 2014 Southern DHB
Matt Parkinson 17 January 2011 Taranaki DHB
Murray Lowe 16 August 2017 Taranaki DHB
Justin Hankins 01 July 2008 Waikato DHB
Matt Molloy  3 November 2016 Waikato DHB 

Estimated cost of compliance

The Act involves additional costs for water suppliers to improve their systems and infrastructure. While the cost estimates vary, and at between $50 million – $275 million they are significant, they will be phased in over several years and must be considered in the context of a sector with assets estimated to be in the order of $5500 million. The Act includes a number of mechanisms to address and minimise compliance costs to suppliers:

  1. phased commencement, giving smaller suppliers longer to plan for implementation;
  2. proportionality of compliance effort to risk, for example under the standards smaller suppliers have less onerous monitoring requirements;
  3. the duty to comply with the Standards is subject to the ‘all practicable steps’ qualifier, which includes cost and affordability as factors to be taken into account in determining whether legal duties have been breached;
  4. The Sanitary Works Technical Advisory Committee has been established to:
    1. monitor and evaluate the impact on local communities of the legislation during the five year lead-in period; and
    2. report back annually on those suppliers not complying with the new legislation, the reasons for their non-compliance, and actions taken to effect compliance.

The costs to suppliers will be negligible for those suppliers who already comply with the New Zealand Drinking-Water Standards. Only those suppliers who are not compliant and who are therefore supplying water of either unknown or unsatisfactory quality will face additional new costs.

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Questions and answers

1. I thought New Zealand had the purest water in the world. What is the need for this law?
Safe drinking-water is a cornerstone of protecting people’s health and it may come as a surprise to many New Zealanders that their community drinking-water supplies were virtually unregulated. We accept regulation of food and other consumer goods, but for water – which we have no choice but to accept from our local supplier – we relied on largely voluntary measures to protect the safety of this water.

A concerted effort over the last 15 years from local government in conjunction with the Ministry of Health has ensured that a large proportion of supplied water is safe to drink. However 16 percent of New Zealanders were still served by water – mostly from smaller rural schemes – that did not meet the New Zealand Drinking-Water Standards. In most cases part of the reason relates to levels of contamination such as faecal material – picked up from human and animal sources in the catchment from which the water is drawn – exceeding acceptable standards.

The drinking-water Act will requires drinking-water suppliers to try and meet the standards. It won’t be compulsory to comply with the standards but suppliers need to take all steps to comply that are reasonably practicable.

2. What does ‘taking all practicable steps to comply’ actually mean I have to do?
‘All practicable steps’ is defined in the Act. If you are a drinking-water supplier this means you have to take all steps that you are reasonably able to do in the circumstances to meet the standards having regard to certain matters including: (i) the means available to meet the standards; (ii) cost and affordability; (ii) the harm that would result if the standards are not met; and (iii) what is known about that harm.

What this means is that suppliers need to understand the risks with their supply and show they have taken all the steps they can to plan to avoid or minimise these risks. If it is too expensive, technically impossible or will result in too little gain as against the cost, then a supplier will be permitted to provide water that does not meet the standards, provided it has demonstrated that it can show it really has taken all practicable steps.

The Act also contains a provision which means that a supplier who is implementing an approved water safety plan is deemed to be taking all practicable steps to comply with the standards. This gives suppliers more certainty as to what they need to do to comply.

3. But is anyone actually getting sick?
High levels of faecal and other contamination can cause sickness. Compared to other developed countries, New Zealand has high reported rates of disease that are potentially caused by contaminated water. Research by the Institute of Environmental Science and Research (ESR) and the Otago School of Medicine shows that rates of sickness are higher in areas where the water does not meet the standards.

4. If the water in cities is OK, why does the Bill apply to them?
The water in cities is good. What is lacking is a mechanism to ensure that something major does not go wrong. The Act requires suppliers to have plans to ensure that major calamities cannot happen. An example of this is Walkerton, a small town in Canada. In May 2000, following heavy rain, animal faecal matter washed into the water catchment. This was an unexpected event, and the water was not well monitored and subsequently not adequately treated. Of the 4000 townfolk, 2321 became ill, 65 were hospitalised, 7 died and 30 will be on kidney dialysis for the rest of their lives resulting from a bacteria E Coli in the water. Another example is Milwaukee, Wisconsin, where 70–100 deaths occurred and over 400,000 people became sick in 1993. Suppliers need to have water safety plans to manage the risk of such events. Some city suppliers already have these plans. The Act creates a common framework for such plans and ensure that all suppliers have adequate plans.

5. Has the Ministry of Health had any requirements on territorial authorities to meet any drinking-water standards in past years?
Since 1984 the Ministry has been encouraging territorial authorities and other drinking-water suppliers to meet voluntary drinking-water standards and has published the results of water gradings since 1993 so the public are informed about the water they are receiving. The Act makes it a requirement for drinking-water suppliers to take all practicable steps to comply with the drinking-water standards.

6. The Ministry says it’s going to cost $500 to develop a water safety plan. I have had quotes of $5000 to $10,000.
Water suppliers have a choice of writing their own water safety plans or engaging a consulting firm to do this for them. Supplies serving fewer than 5000 people can participate in the Ministry of Health Technical Assistance Programme where they will receive training and assistance in writing the plans. Other than staff time, there is no cost to the water supplier if they choose to participate in the technical assistance programme – so the cost in these cases should actually be less than $500. Supplies that serve more than 5000 people will not be eligible for the technical assistance programme, however those water suppliers with competent staff will in most cases be able to adapt guidance material provided by the Ministry to develop a water safety plan without the use of consultants. Only if a supplier chooses to use a consultant might the cost begin to approach $5000–10,000. Regardless of who prepares the plan it is essential that the person who is responsible for the supply has a full understanding of the plan as they are the person who will put into effect the things required by the plan. They need to be fully involved in the preparation of the plan.

7. Do I have to have treated water for livestock? Wouldn’t this cost a lot of money for no good reason?
It will not be necessary to try and make water that is used to supply stock compliant with the standards. Where a water supply supplies both drinking-water for people and water for agricultural purposes it is classified as a ‘rural agricultural drinking-water supply’. Such supplies face no duties under the drinking-water standards until 1 July 2013 at the earliest. The drinking-water standards will be amended to determine exactly how such supplies will be managed, and the Ministry is seeking opinions on how this should be done. For example, this might be through the use of a ‘Point of Entry’ system such as a filter and/or UV lamp. Many such water supplies are run on this basis already.

8. We are a small community and can't afford big costs associated with upgrading water supplies. What help can the Ministry give us?
The drinking-water assistance programme (DWAP) will provide technical advice and funding to increase the ability to meet the standards and reduce the costs for local communities. This will be achieved in two main ways. Firstly, technical assistance will reduce the cost of preparing risk management plans and will help suppliers use the system that they already possess in the most efficient way. Often an apparent need for costly upgrades may be avoided simply through better use of existing systems. Secondly, where the technical assistance programme shows that the need for a better system is unavoidable, the capital assistance programme may be able to provide some or all of the cost.

9. Is it true if I drink my own tank water it will build my immunity and I won’t need to treat it?
Whether to treat tank water is a decision for each owner depending on individual circumstances and preference. It is not regulated by the Act. It is true that while healthy adults will gradually get used to the water, they will still get sick more often than if they had clean water. The illness can be mild or severe and can in some cases lead to other more serious health problems. Also visitors to your place who do not have that immunity and children or the elderly who may be more vulnerable, could become sick.

10. My district council says my rates are going to go up by at least $300 because of the new Act. Is this correct?
If you live in a city it is unlikely that the Act will result in an increase of more than $1 or $2 per annum, if that. Smaller rural supplies will generally require higher investment but the Ministry of Health’s technical assistance programme can help suppliers to better manage their existing systems and minimise the need for further investment. In cases where the state of the water supply system has been neglected for many years it may cost more to meet the standards. However the Ministry of Health’s drinking-water assistance programme (DWAP) will be able to assist the community to minimise these costs by assisting the community to identify the cheapest option and meeting some or all of the cost.

11. How will the drinking-water assistance programme (DWAP) help keep my costs down while ensuring I comply with the drinking-water standards?
The technical assistance programme will help communities to identify the potential problems with their drinking-water and develop a plan to manage these risks. Using this plan the community will get help to manage the operation of their supply so that their system will deliver the best possible quality water with the least risk. If it proves impossible to provide safe drinking-water with the best use of the existing system, the technical assistance programme will assist the supplier to apply for financial assistance from the capital assistance programme.

12. If I have my own water tank supply, do I have to comply with the drinking-water standards?
The drinking-water Act does not apply to domestic household supplies if the house has its own water supply.

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Regulatory Impact and Compliance Cost Statement

Two Regulatory Impact Statements were produced for the Proposed Health (Drinking-Water) Amendment Bill. The first was produced for the November 2000 Cabinet paper which resulted in Cabinet approval to ‘amend the Health Act 1956 to strengthen the legislative framework for drinking-water supplies’.

This Regulatory Impact Statement did not contain a Business Cost Compliance Statement as this was not yet a requirement in 2000. The second Regulatory Impact Statement was produced for the June 2005 Cabinet paper which resulted in a Cabinet decision to modify the original approval . It included a Business Cost Compliance Statement.

The documents are available below.

Download a Word version which combines the above two documents (doc, 119.50 KB)

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