New Zealand Drinking Water Regulations & Legal Requirements

They’re the laws and rules that set out who must supply safe drinking water and how they prove it. The main ones are the Water Services Act 2021, the Drinking Water Standards (the legal limits for contaminants) and the Quality Assurance Rules (testing, monitoring and reporting). The Water Services Authority (Taumata Arowai) oversees them.

Anyone who supplies drinking water to other people is likely to be a drinking water supplier. That includes councils, and businesses and organisations that supply water to staff, customers, students or the public, such as cafes, schools, marae, campgrounds and farms with staff housing.

Since August 2025, supplies that serve only households, with 25 or fewer people, are no longer drinking water suppliers. A home that supplies only its own household is a domestic self-supply.

If your supply was running before 15 November 2021 and isn’t registered yet, you have until November 2028 to register and until November 2030 to meet all your legal duties. Any supply set up since 15 November 2021 must be registered and comply from the day it starts. The duty to supply safe drinking water already applies to everyone.

Changes to the Water Services Act 2021 came into force in August 2025:

• The regulator is now called the Water Services Authority (Taumata Arowai).
• Household-only supplies serving 25 or fewer people are no longer drinking water suppliers.
• Drinking Water Safety Plans are no longer needed for supplies serving 25 or fewer people.
• Registration renews every five years instead of every year.
• Existing unregistered supplies now have until November 2028 to register and November 2030 to comply.

New Quality Assurance Rules also start on 1 July 2027. Read the full list of changes.

It’s New Zealand’s national water services regulator. It registers drinking water suppliers, sets the Quality Assurance Rules and Acceptable Solutions, monitors suppliers and enforces the law. Until August 2025 it was known simply as Taumata Arowai.

The regulator can take enforcement action to protect public health. This can include written warnings, compliance orders, fines or prosecution. Suppliers may also have to improve their treatment, increase monitoring or issue boil water notices until the water is safe again.

Usually, yes. If your business supplies drinking water to staff, customers or guests, it’s likely to be a drinking water supplier, even if it serves 25 or fewer people. That includes cafes, accommodation, schools, marae and farms with staff housing. Only household supplies serving 25 or fewer people are exempt.

If you’re unsure, Aqua Works can look at your water system and tell you what applies. Call us on 0800 278 296.

A Drinking Water Safety Plan (DWSP) sets out the risks to your water supply, from source to tap, and how you manage them. Most registered suppliers need one, but supplies serving 25 or fewer people no longer do. Suppliers confirm or update their plan each time they re-register, every five years.

Aqua Works can assess your supply, test your water, design the treatment you need, such as UV disinfection and filtration, and help prepare your Water Safety Plan. Call us on 0800 278 296.

We help businesses and private water suppliers meet the rules. We can test your water, assess your system and design treatment to suit your water source, including UV disinfection, filtration and full treatment systems. We also guide you through the monitoring and paperwork the regulator expects.