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Future environmentalists swapped the classroom for the Manuherikia River last week.
Omakau School children ventured to the river on Tuesday as part of their lessons on water quality, alongside their teachers and Enviroschools facilitator Anna Robinson.
The group used kits, including Niwa's Stream Health Monitoring and Assessment Kit, to analyse the water quality.
"The Shmak kit gives us a snap shot of the water quality just today,'' Ms Robinson said.
Shmak kits feature a thermometer, pH kit and a clarity tube to look at sediments in the water.
It also features a macro-invertebrate document and instruments, rope to measure velocity and a conductivity meter to look at dissolved particulates unable to be seen with the human eye, which can hold an electrical current.
Data collected helps determine the quality of the water and whether or not the water has generally been good.
"So, an example of that is if you've got lots of your good critters like your mayflies and dobsonflies, they are there because the quality of water has been good for a long period of time.''
Clarity tubes helped give children a "snapshot'" of what had been happening in the river, particularly in regards to the weather.
"For example, we had lots of rain here and snow last week, so that rain is now coming down off the hills, the snow is melting, which is increasing or decreasing the clarity.''
Ms Robinson said the testing had helped the children develop their understanding of what it means to have a healthy waterway.
She said re-testing the waterways periodically would also help them understand seasonal variations, and how much of an affect there is if any action is taken to improve the water.
Information they gathered could have broader community impact too.
She said it could provide valuable information for the wider catchment, as more connected and cohesive work is done to restore waterways.
"The bigger picture of this is actually about everyone working in together - the school students, the council, the farmers and all those other interest groups working in together to provide a really healthy catchment.''