Six kilometres of a stream within Karioi Forest on the slopes of Mt Ruapehu is being restored from nothing to a flowing, living entity this year, Keith Wood says.

It's just one of the changes that made him and wife Mercia finalists in New Zealand's 2016 Green Ribbon Awards.

The awards celebrate environmental achievements by New Zealanders.

The couple are finalists in the Kaitiaki Leadership category. They were nominated by Dave Milner, the manager of Ngati Rangi Trust's environmental unit, for their contribution to environmental work in Ngati Rangi's Ruapehu rohe (area).

Advertisement

Mrs Wood didn't want to talk about the nomination but her husband said she was its inspiration. "Our wahine are closer to Papatuanuku and nature. They feel the negative stuff more. She's the one that keeps me grounded and continues to feed me insights on how the material world might be."

For the last 20 years, Mr Wood has put endless unpaid hours into the work of environmental advocacy and mentoring - on top of holding down a full-time job. He's made many submissions to resource consent applications and been to many, many meetings. The health of mountain waterways has been a prime focus, and there are 26 of them across the rohe.

"We as Ngati Rangi are lucky, because we are at the headwaters of so many of these streams and we see them in their pristine, unmodified state. It's our responsibility to make sure they leave our area in the best state that they can be."

Many of them are diverted north, to generate electricity in the Tongariro Power Development. Ngati Rangi and other Whanganui tribes spent years fighting those diversions in the courts.

Then they decided to work with electricity generator Genesis to improve the health of the waterways. Under a new agreement, enough water is being returned to the Tokiahuru, Wahianoa, Makahikatoa and Tomowai streams to give them permanent surface flow from their sources - even if it's only a small flow after their diversion dams.

All are headwaters of the Whangaehu River, and flow off the southern and eastern slopes of Mount Ruapehu. All were 100 per cent diverted from the 1960s until four years ago. Their small restored flows are being monitored.

"That's going to be a great process for us as Ngati Rangi. Seeing dry riverbanks rips at the soul of people. It's unnatural," Mr Wood said.

He's also mentored young people in the Kiwi Forever programme, now in its 11th year. And the trust hosts groups of students from Massey and other universities for multi-day environmental programmes.

Mr Wood often acts as guide, "introducing people to our natural environment in the way we see it - as living beings, basically".