Skip to page content
You are here: Home > Stories > Capturing river cleanliness on camera

Capturing river cleanliness on camera

Young women in Rotorua are exploring the health of local rivers and sharing their findings through filmmaking.

Shooting a mermaid scene

Rotorua Girls' High School rangatahi are being shown the ropes in scientifically comparing – and filming stories about – the health of their local rivers.

As part of a project called Indigenous Sparks that marries science and culture, the students are learning how to get an idea of a river’s purity and vitality through scientific testing.

Rivers hold tremendous value for Māori throughout Aotearoa, as encapsulated in this whakataukī (proverb): Kei te ora te wai, kei te ora te whenua, kei te ora te tangata (if the water is healthy, the land and people are nourished).

Testing for phosphatesWith help from Waikato University scientist David Hamilton, the girls have tested several streams and rivers around Lake Rotorua: from Puarenga stream near the Ngāpuna wastewater works to Hamurana stream on the opposite side of the lake.

The students checked the acidity of the streams using strips that changed colour depending on the sample’s pH. Then they tested for phosphates (found in fertilisers, cow poo and wastewater) – the bluer the indicator’s colour, the higher the concentration.

The pupils also looked at the clarity of the water by looking through a transparent tube with a visibility marker inside.

Last, they investigated what bugs lived in the water – the higher the number and the broader the range of species, the better.

Looking at bugs in the water

When asked what surprised them most, 14-year-olds Jessica, Kiri and Faye said that they didn’t realise just how polluted their local rivers were, and how much farmland runoff and works chemicals can contribute to this.

The girls also say that their results suggest that Puarenga is the most polluted site, with this stream having the least healthy readings.

“The water is clean here [at Hamurana] but we also found out the stream near our school is actually quite dirty,” says Anipatene, 14.

“My favourite part has been doing the clarity testing – which is also cool because some of the animals actually come up to you while you’re doing it”.

Testing how clear the water is

The students also captured their activities on camera, with help from professional filmmaker Logan Judd of Powered On Videography, to create river-themed short films. 

Fourteen-year-old Jada’s group shot a documentary about the science of river monitoring and the differences between two sites, while classmate Awhi and her team filmed a more conceptual narrative about New Zealand’s environmental transition from utopia to dystopia.

“I liked the acting part 'cause it was fun,” says Pania, 14.

The filming sessions also involved interviewing David, in which he explained what the students’ scientific findings say about river health.

Student interviewing a scientistStudents interviewing a scientist

Once the girls had all captured their scenes on camera, they went back to the school to edit their footage.

“I loved doing all the outdoors stuff,” Awhi says. “Most of the time we’re in classrooms or on our laptops, and I prefer being outside.

Kylie Hill, Assistant Head of Maths, adds: "This is a fantastic way to give the students an idea of how maths and science can be used in the real world in a way that is meaningful to them.

"It’s added depth to my teaching too, because these are relevant examples I can continue using in class to show how maths can help us improve our lives."

Girls editing their footagePhoto credit (girls with pipettes): PTC Trust

Read more about the project on the PCT Trust website

A similar session with students at Horowhenua College led to winning the 2017 Reel Earth Film Festival with this video entry:

3 Boys and a River

About the project

Indigenous Sparks logoRGHS logoIndigenous Sparks™ is run by PTC Trust with support from the Unlocking Curious Minds contestable fund. The session outlined in this story was in partnership with Rotorua Girls' High School.


Unlocking Curious Minds

Unlocking Curious Minds supports projects that excite and engage New Zealanders who have fewer opportunities to experience and connect with science and technology.

Find out more

View all stories