ANZECC water quality guidelines - FAQs
10. The concept of using reference sites to determine the natural levels of stressors or natural biological condition, is an important feature of the Guidelines. In many parts of New Zealand, it is almost impossible to find reference sites of a sufficiently high quality for this purpose. It is also likely that high quality reference sites would result in unrealistic comparisons and expectations of surface water quality in highly modified systems of New Zealand.
The Guidelines acknowledge these arguments and argue that high quality reference sites are not essential in the assessment of water quality for disturbed ecosystems. Rather, modified water bodies of the best environmental quality in the region serve as reference targets.
