National, regional and local agencies regularly monitor the country’s waterways. They use physical, chemical and biological indicators as evidence of water quality.
Dr Eloise Ryan explains why Waikato Regional Council monitors water. Select here to view the video transcript.
The following resources explore water quality and how and why we monitor it.
Articles
- Water quality
- Water quality in Rotorua lakes
- 1080 and water quality
- Students help restore mauri to the Oruarangi Stream
- Testing the waters – Connected journal article
Videos
Transcript
DR ELOISE RYAN
In the Waikato region, we follow national government guidelines. For example, for drinking water, there are Ministry of Health guidelines that stipulate the levels that are safe to drink. When it comes to swimming and recreation, there’s another set of guidelines by the Ministry for the Environment, and they determine how much bacteria is safe for people to swim in in our rivers and lakes and streams.
When it comes to water quality that protects our ecosystems and our aquatic life, there’s another set of guidelines, and they stipulate levels that are safe for things like nutrients and sediment and bacteria as well.
Recreational use water quality standards are all about keeping people safe, and that’s got to do with the amount of bacteria or toxic algae in the water. So that’s why the recreational water quality standards cover bacteria. The indicator bacteria we test for is called E. coli bacteria, and that occurs in the guts of warm-blooded animals, for example, humans, possums, ruminants like cows or sheep. So it’s not natural, it entered the waterway through our guts and our faeces.
We measure water clarity at the council to determine safety for swimming. For example, people don’t like swimming in water that’s full of sediment – they like to swim in nice clear water. So we measure it, and basically, if you can see less than 1.6 metres through the water, it’s not very clear and not very suitable for swimming. So we use that as part of our swimmability indicator, whereas our other water quality standards cover many other things.
So the Waikato Regional Council monitors a lot of different indicators of water quality – we monitor around 32 a month – but we look at seven different indicators to say whether the water is passable or not. And those indicators include temperature, turbidity, pH, the nutrients – total nitrogen, total phosphorus – ammonia and dissolved oxygen, because like humans, plants and animals need oxygen to breathe as well.
Acknowledgements
Dr Eloise Ryan
Aroha Salu
Alicia Caitlin
Waikato Regional Council
Footage of man fishing, Whaka Trout
Acknowledgement
This video has been developed in partnership with the Waikato Regional Council as part of the Rivers and Us resource.
