Context to the Standards
The Water Services (Wastewater Environmental Performance Standards) Regulations 2025 (Standards) have now been published and will take effect on 19 December 2025 (with the exception of regulation 8 and Part 2, which come into force on 19 December 2028). These follow the proposed wastewater environmental performance standards discussion document released by Taumata Arowai Water Services Authority in February 2025 and are largely in keeping with the proposed standards, with a few notable exceptions.
The Standards are driven by the need to reconsent approximately 60% of New Zealand’s public wastewater infrastructure over the next decade, with population growth and urban development further increasing demand for infrastructure renewals.
What are the Standards?
The Standards regulate:
- Discharge of biosolids to land
- Overflows from wastewater networks and bypasses of wastewater treatment plants
- Discharge from wastewater treatment plants into water
- Discharge from wastewater treatment plants to land.
They must be applied in:
- Future resource consent renewal processes for wastewater plants
- Any new consents for existing or new wastewater infrastructure.
This means that the Standards will significantly impact wastewater treatment plant consent applications, especially given that – as provided for in the recent RMA amendments – they override other Resource Management Act 1991 planning instruments (excluding regional or district planning instruments that give effect to Te Ture Whaimana o Te Awa o Waikato – the Vision and Strategy for the Waikato River). The Standards also have the effect of standardising consent conditions as most activities will be subject to a number of mandatory conditions.
One major change to the status quo is that the section 124 protection for operating an expired consent where a reconsenting application is made will only be allowed for two years (coming into effect on 19 December 2028). This change, along with others, is intended to speed up wastewater treatment consent processes and provide communities with clear expectations about treatment quality.
Overview of the Standards
The discharge of biosolids to land standards set out when a discharge is a controlled, permitted or discretionary activity using a risk-based matrix:
The overflows and bypasses standards classify discharges of wastewater via existing engineered or uncontrolled overflow points, or bypasses of wastewater treatment plants, as a controlled activity. Applicants must class overflow points as high, medium or low risk when applying for consent and the standards require certain mandatory conditions to be imposed such as telemetric monitoring and information provision. A notable change from the proposed Standards is that discharges from new engineered overflow points are no longer classified as a controlled activity, as the Standards do not specify an activity status for these discharges. The overflows and bypasses provisions come into force on 19 December 2028.
The discharge of treated wastewater to water standards apply different standards based on the level of dilution in the receiving water body, including rivers, lakes and the coastal marine area (open ocean, estuaries etc). For example, rivers must be classified on a scale of high, moderate, low and very low dilution. Treatment requirements and discharge concentration limits are generally less stringent where the discharge is to a water body with higher levels of dilution. The February 2025 discussion document considered whether contaminant measurements should be based on the 7-day median annual low flow, the median design flow or the annual median. The Standards generally adopt the annual median as the measurement for contaminants. As with the new engineered overflow points, the Standards also do not specify the activity status for discharging wastewater to into water.
Similarly, the discharge of treated wastewater to land standards do not specify the activity status for discharging wastewater to land. Instead, resource consent applications must include a site assessment, which assigns a land class based on environmental and public health risk factors and the drainage capacity of the site. The applicable discharge concentration limits then vary based on the assigned land class and whether the site is a slow or rapid-infiltration discharge site.
Our team of Local Water Done Well experts are leaders in local government water reform and specialise in assisting councils with the implementation of Local Water Done Well. We would be happy to talk to you about any questions you have on the implementation of the Standards.
