New Zealand's Wastewater Environmental Performance Standards

The Water Services (Wastewater Environmental Performance Standards) Regulations 2025 (WEPS) were released on 20 November 2025. The WEPS include requirements, limits and conditions relating to activities associated with wastewater networks. They aim to standardise New Zealand's approach to consenting wastewater networks and wastewater treatment plants in regard to discharge of treated wastewater to land and water, discharge of biosolids, as well as overflows and bypasses. They apply to all public wastewater networks and their operators.

This insight article explores the need for a standardised approach, how the WEPS will be implemented, and an overview of what each of the new standards entails.

 

Why do we have new standards?

The WEPS were introduced as part of the Local Water Done Well (LWDW) framework. The LWDW framework aims to recognise the importance of local decision-making and flexibility for communities and councils to determine how their water services should be delivered in the future. Read more about the LWDW reform package in our previous article.

Across the country, there are 334 publicly owned wastewater treatment plants (WWTPs), 331 of which are operated by a council, or a Council Owned Organisation (COO). Over the next 10 years, approximately 60% of the existing consents for WWTPs will need to be replaced, of which 20% have already expired. WWTPs currently operate on expired consents for an average of five years under section 124 of the Resource Management Act 1991 (RMA).

Given this, introducing nationally consistent standards has been seen by the government as an opportunity to make the consenting process less complicated and costly.

 

Implementation

With two exceptions, the WEPS will come into force on 19 December 2025. Part 2 of the WEPS, which regulates overflows and bypasses, and regulation 8, which applies to ongoing operation of expired consents, do not come into effect until 19 December 2028. Given that the overflow and bypass standards are not coming into effect until late 2028, this gives service providers three years to determine if existing infrastructure needs upgrading, or new infrastructure needs to be built in order to be compliant.

Although the majority of the WEPS are in effect from next month, given that existing wastewater treatment facilities will need time to comply with the WEPS when seeking consent for new WWTPs and/or replacement consents for existing facilities, the discharge to land and water regulations have specified time periods to allow for required upgrading to occur.

For example, regulations 83 and 84 (discharge to water for small and other WWTPs) enable a three or five year upgrade period to be included as a condition on consent respectively, and regulation 102 (discharge to land) also enables a five-year upgrade period to be imposed through conditions on resource consents for discharges to land.

Alongside the WEPS, the RMA was amended in August 2025 via the Local Government (Water Services) (Repeals and Amendments) Act 2025 (Repeals and Amendments Act) to include specific provisions as to how the WEPS are to be given effect to by local authorities (see sections 58JB and 58JC of the RMA) and how they are to be addressed via extant wastewater consents (ie, those that are current but expiring) are to be treated (see sections 139B to 139F of the RMA). These provisions also provide the framework for live consent applications lodged prior to the Repeals and Amendments Act and WEPS coming into force, and application of section 124 of the RMA.

 

The standards
Discharge of biosolids to land (regulations 10–19)

The biosolids part of the WEPS will apply if:

• the biosolids result from treating wastewater in a WWTP and the discharge is for the purpose of fertilising the soil or improving the condition of the soil;
• there is any odour resulting from that discharge; and
• the effects of the contaminants adversely affect the environment or public health.

 

The regulations in this Part are based on the Guidelines for Beneficial Reuse of Biosolids, released early 2025. These Guidelines have informed the WEPS to provide:

• a grading system for processing biosolids with corresponding activity status (permitted, controlled or discretionary) for how and when biosolids can be reused and stored;
• additional requirements and allowing consent authorities to impose additional conditions on a resource consent where biosolids pose a greater risk due to their lower grade; and
• monitoring, reporting, and record-keeping on the grade of the biosolids. Further consent conditions can be imposed on consent holders relating to monitoring, record-keeping, consultation, reporting and provision of information at the consent authority's discretion.

 

Management of overflows and bypasses (regulations 20–39)

Part 2 of the WEPS regulates overflows and bypasses.

In Subpart 1, there are provisions that relate to overflows from wastewater networks, including from existing and new engineered overflow points and uncontrolled overflow points. The provisions aim to ensure there is more visibility regarding when, where and why overflows occur within the wastewater network. The WEPS:

• require network operators to use wastewater risk management plans to identify where there are risks of overflows and how they should be managed, controlled and eliminated. The regulations set out specific criteria to be applied when determining whether the overflow is low, medium or high risk;
• impose monitoring and reporting requirements for overflows from wastewater networks; and
• specify that existing and uncontrolled overflows are a controlled activity under the RMA. As well as this, they set out that new engineered overflows require resource consent, with mandatory conditions a consent authority must impose on a resource consent relating to overflows.

Subpart 2 relates to bypasses. It specifies bypasses are a controlled activity and sets out mandatory conditions for a resource consent that must be imposed.

Given this part of the WEPS is not coming into effect until December 2028, there is more time to assess how it will affect wastewater networks and operators.

 

Discharges from WWTPs to water (regulations 40–84)

The discharge to water part of the WEPS sets discharge concentration limits for specified contaminants. There is a range of requirements depending on the receiving environment, ie, rivers, lakes or coastal marine areas.

The regulations set out requirements for sampling, testing and record-keeping. There is also a requirement that consent conditions must include specific actions to be taken by the consent holder if a WWTP exceeds the relevant discharge concentration limits.

Regulations 73 to 76 address mixed discharge schemes, where there is discharge to a river in some circumstances, but when those circumstances do not apply, the wastewater is discharged to land, stored or managed in another way.

This standard will be implemented as future resource consents come up for renewal and will be required to be implemented as part of any new consent for existing plants or new infrastructure.

 

Discharges from WWTPs to land (regulations 85–116)

The discharge to land part of the WEPS addresses operational requirements, and strengthens monitoring, record-keeping, reporting and planning requirements for discharges from WWTPs to land.

 

Operational requirements (Part 4, Subpart 1)

The WEPS impose a risk-based framework for discharging treated wastewater to land and impose monitoring and reporting arrangements. A resource consent application must include a site assessment, of which a land class must be assigned for the purposes of determining discharge limits. To determine a land class, there must be a risk assessment conducted, and requirements are set out under regulation 92 of the WEPS.

Resource consents must now include a condition requiring the consent holder to prepare and maintain an operations and maintenance manual, and a resource consent application must include a draft of that manual. Regulation 101 sets out the mandatory information this manual must include.

Similarly to the discharge to water standard, this standard will be implemented through future resource consents as they come up for renewal or where new infrastructure is consented.

 

Monitoring and reporting (Part 4, Subpart 2)

The WEPS also set out the required information needed for monitoring, record-keeping and reporting for discharges of wastewater to land. Regulation 104 specifically enables consent conditions to impose additional or stricter requirements on a consent.

There must also be a management plan prepared as part of a resource consent application to discharge wastewater. Regulation 116 sets out the contents of the management plans.

If you would like to understand what these standards mean for you, please reach out.