Water Quality Index - Methodology

Northland Regional Council (NRC) undertakes State of Environment (SoE) monitoring at 52 rivers around Northland on a monthly basis. The results of the SoE monitoring are compared to national guidelines such as the National Policy Statement for Freshwater (NPS-FW). These national guidelines provide a useful framework however can sometimes misrepresent the natural environment for Northland. For this reason, the Northland Regional Council developed this Water Quality Index to provide a more regional context, assessing results of key attributes against ‘natural state’ Northland reference sites.

This document is the background science behind the river report cards (to be published in September 2024).