Water NZ have published an informative document for PROPERTY OWNERS with onsite wastewater treatment systems (download here) https://www.waternz.org.nz/Attachment?Action=Download&Attachment_id=2976
This document addresses frequently asked questions and covers topics such as: manufacturers, installers, types of systems, the basics for caring for an OWMS, local rules and regs, responsibility, servicing and failing systems. A must read 👍