Community and Education news

Mangakahia River
6 November 2019

NZ River Awards 2019 River Story Finalist Mangakahia River, Whangārei

Cawthron is proud to be running the 2019 New Zealand River Awards. As part of the celebration, the River Story Award category recognises interesting and compelling stories about individuals, businesses and communities working to improve the health of our rivers.

The stories are inspirational projects that involve community collaboration, science and innovative ways to address freshwater-related challenges.

This year, eight stories were selected as finalists and from these, the judges have selected the top three. The work being done to protect and restore the Mangakahia River in Northland is our third story.

Andrew Booth is the third generation of his family to farm beside the Mangakahia River, a major tributary of the Wairoa River which runs into the Kaipara Harbour – New Zealand’s largest estuarine ecosystem. He is enthusiastic about the local environment and especially the river where he swam as a child (and still swims now).

He is committed to leaving the land and the river in better condition than he found them, and has put considerable effort into fencing, planting and effluent management. Today 50 per cent of water passing through the farm travels through a wetland or a swamp before reaching the Mangakahia.

Andrew and his wife Vicky sharemilk 420 cows on 174 hectares. Ten years ago, when Andrew returned to the family farm after studying at Lincoln University and working on several farms in New Zealand, he started fencing off the river from livestock. This reduced bank erosion along his farm’s 5km river boundary. Next he fenced remaining small drains on the farm, along with pockets of native bush. Within a few seasons the protected bush was regenerating. It was fortunate that steep land with remnant totara had never been cleared.

Next Andrew turned his attention to riparian planting to capture more sediment before it reached the river. Critical areas were boggy paddocks and selected sections of riverbank. Weeding, while not as exciting as planting, was also necessary and it is an ongoing battle to keep on top of convolvulus.

While most of the labour and resource has been provided by Andrew, the wider community has got involved in recent years. The Integrated Kaipara Harbour Management Group and Northland Regional Council have provided plants, and school students have helped put them in the ground.

“There are kids who don’t get the opportunity to visit a farm. I really enjoy having them here and showing them what happens; they start to understand what you’re doing, and can see what you’re trying to achieve by farming sustainably,” says Andrew.

When the farm was initially cleared, a large natural swamp was left untouched. This catches nearly half the run-off water and today is a flourishing wetland. Andrew is now developing a second wetland on the other side of the farm.

“Before it reaches the river, I want to filter as much water as I can and creating the second wetland will result in 90 per cent of the farm run-off water being filtered. This will improve water quality and I reckon that we already have lower E. coli and nitrate levels than when I was a child. I also want a better habitat for wildlife,” says Andrew.

Increasing environmental awareness across New Zealand, and support from his family, have made the change process relatively easy for Andrew. For the latest wetland restoration, he is working with Northland Regional Council, and the project is being used as a case study for what can be achieved by filtering farm run-off.

Sustainability is important to Andrew and his vision is to show that, “dairy farmers are doing all they can to enhance the land they farm. I am always looking for ways to improve the way we look after our land.

“I am not alone in undertaking riparian management projects. Thousands of farmers across New Zealand are doing all they can to help improve environmental sustainability,” says Andrew.

This collective action reinforces Andrew’s commitment to look after his land, and particularly the river that has been there all his life. His own children now swim in the river just as he did, and Andrew believes there is “no reason for it to get to the state where it’s unswimmable.”