Fast eroding Ōhau River bank threatens notable tree: A revolving tale

The Northern Rata, left, sits only a few metres from the eroding riverbank in Kimberley Reserve.

One of Horowhenua's notable trees has been bristling its branches in recent years as it watches the water of the Ōhau River edging ever closer to it each year.

Some of its roots are already exposed, sticking out of the fast eroding riverbank.

Calls for help have gone out to both Horowhenua District Council, who has protected the tree, and Horizons Regional Council, who is responsible for the course of the river.

The Ohau River is eating away at the left bank at Kimberley Reserve, exposing roots belonging to a 100-year-old Northern Rata.

However, with another winter looming, a few tree-loving locals argue that bureaucratic action is taking too long and they fear for the tree's life as winter storms come along with serious flooding that easily erode the bank further.

Dan Brizzle (Keep New Zealand Beautiful life member) and Joan Leckie (Forest and Bird) estimate the Northern Rata, or NT16 on the district council's Register of Notable Trees, to be at least a century old.

In those years it has stood as a witness to a large chunk of Levin's settler history. Many visitors have picnicked or camped beneath its expanding canopy.

The neighbouring Ōhau River is prone to changing its course and carries along with it an enormous amount of rocks and pebbles, enough to sustain an excavation industry.

This Nothern Rata tree at Kimberley Reserve is ion the council's registry of Notable Trees. It is under threat from erosion by the Ohau River.

The river hits a corner before it encroaches on to the Kimberley Reserve, has deposited a lot of rocks on the other side of the river, forcing the river to take the easy way out and crash into the opposite bank, metres away from the Northern Rata, slowly chomping away at the bank.

An old Fish & Game access road to the river has already been washed away completely and elsewhere on the bank someone has carved out steps to provide access to the river.

There have been meetings between Horizons and Horowhenua councils' staff and they have been on site to have a look and say they are not working on a plan to save the tree.

While acknowledging that the "riverbank is encroaching towards the tree and there are some small roots now protruding from the bank", Horowhenua District doesn't seem overly concerned, unlike Mr Brizzle and Mrs Leckie, because "The riverbank edge has not yet encroached within the canopy of the tree."

This Northern Rata in Kimberley Reserve has been there for at leasat a century.

Council staff say they estimate the tree to between 80 and 100 years old.

Horizons said, "Our engineering officer for the southern region has contacted Horowhenua District Council's parks and reserves team (the tree is in the Kimberley Reserve which they manage) and is meeting with them to discuss what can be done.

"Horizons Regional Council staff have met with a representative from the Horowhenua District Council at the site. We are currently looking at options and costs in consultation with our design engineer," they confirmed a few weeks later.

The eroded bank of the Ohau River at Kimberley Reserve, exposing roots of the Northern Rata.

Asked what progress is being made, a Horizons spokesperson said there was nothing to report as "the representative of HDC we are working with has expanded what was originally asked of Horizons and at this stage we are unable to confirm the funding or the timeframe for the works as we are still working through the details with HDC".

Brizzle and Leckie said they had been told some weeks ago by a district council staffer that it is unlikely Horizons will be able to find the funding to save the tree. They have been knocking on many doors, and repeatedly so, to draw attention to the plight of the tree.

They estimate the riverbank has been eroding at the rate of a few feet each winter and fear for the tree as the canopy is only metres away from the bank.

The pair have done their best these last few months to get action from both councils but feel frustrated at the slow progress. They have also spoken to regional councillor Emma Clarke as well as Lindsay Poutama, chief executive of Te Rūnanga o Raukawa.

The exposed tree roots and eroded bank. Ohau River at Kimberley Reserve.

Regional councillor Emma Clarke told them only the other week, "I would like to hope that when the budget to save the Northern Rata is presented to council, that they see past just the monetary impact and see how tragic it would be to not be able to preserve such a historic piece of Horowhenua landscape," she said.

"I think they can put a temporary measure in place, using large concrete blocks," said Brizzle.

He even knew where to procure these concrete blocks from.

Their concerns have remained constant for months and the constant door knocking, and its cascading effect of those people ringing and meeting with more people, seems to have borne fruit at last.

The latest news is that Horizons councillors discussed the plight of this tree this week, and have asked for immediate short term action.

Some of the exposed roots belonging to the Northern Rata in Kimberley Reserve.

They want some channel stoppage work to be done, to take the pressure off the bank straight away. When it comes to a permanent solution, "We will fund 30 per cent of the cost of saving this tree," Emma Clarke said.