Resources
Research and a range of other sources of insight informed the development of the wastewater standards.
Guidance
The following guidance materials were developed to support the implementation of the national wastewater standards.
Engagement
We undertook a public consultation on the first set of national wastewater standards from February to March 2025. The report on our engagement can be found here.
Technical reports
Technical advice on wastewater standards helped inform the standards.
Database of wastewater resource consents
We developed a database of wastewater resource consents to inform the first set of wastewater standards. The consents database summarises information from resource consents regarding wastewater discharges from publicly owned and operated wastewater treatment plants and networks. This includes detail about the plants, their technology, what contaminants are controlled or monitored (and their corresponding limits) alongside other consent conditions.
The database reflects the information available to the Authority when the wastewater standards were developed in late 2024. The information summarised in the database is available from regional councils – either on public websites or via the Local Government Official Information and Meetings Act 1987. The Authority intends to keep the database updated and may expand it to include resource consents for other matters, such as discharges to air from wastewater treatment plants.
We intend to keep the database updated and may expand it to include resource consents for other matters, such as discharges to air from wastewater treatment plants.
You can access the consents database here.
Case studies
Case studies provided insight into iwi and hapū experiences of the existing resource consenting process and wastewater treatment arrangements at six wastewater treatment plants.
- Read the case study overview report. Each individual case study is in the appendix. (Updated 18 April)
- Find out how this iwi and hapū insight informed the proposed national standards
Regulatory impacts and costs
The regulatory impact statement (RIS) provides a high-level summary of why the standards were needed, the options for developing standards and their associated costs and benefits, and the consultation undertaken. Costs saving estimations were informed by case studies done as part of the RIS.
- Read the interim regulatory impact statement
For small plants specifically, the Department of Internal Affairs commissioned a study through National Infrastructure Funding and Financing (NIFF) to provide examples of the impact of the proposed wastewater environmental performance standards for discharges to water (the small plant standard).
Related research and guidance
- Beneficial Use of Biosolids and other Organic Materials on Land (Good Practice Guide) outbound- Water New Zealand
- The cost of consenting infrastructure projects in New Zealand –outbound Infrastructure New Zealand
- National stocktake of municipal wastewater treatment plants –outbound Department of Internal Affairs
- The New Zealand wastewater sector outbound– Ministry for the Environment