Historical Māori remains have been unearthed as banks of the Nūhaka River erode away.
Police were alerted about 8.30am yesterday when the kōiwi (human skeletal remains) were discovered at Nūhaka.
Ngāti Rakaipaaka iwi confirmed the remains were historical and from an urupā known to be in the area.
Ngāti Rakaipaaka trustee and environmental officer Graeme Symes said the urupā was on the bank of the river and kōiwi were exposed as the bank eroded away.
He thought it was related to the flow of the river.
"They show up out of the blue every now and again," he said.
"Probably when they were buried there, 200 years ago or more, the flow of the river was different - the dynamics of the river, the forces of erosion, nature itself."
He had found some kōiwi exposed at the site about three months ago.
The urupā had unmarked graves with tīpuna of Ngāti Rakaipaaka buried there.
There was another urupā on higher ground nearby where he planned to rebury the kōiwi last night.
This has always been an issue and was exacerbated when the river mouth was blocked, causing the water levels in the river to rise, he said.
They had not yet noticed the effects of sea-level rise.
Ngāti Rakaipaaka planned to move the remaining kōiwi away from the flow of the river to urupā on higher ground, Symes said.
Symes said Ngāti Rakaipaaka had approached the Department of Conservation's fund Jobs for Nature to ensure their wāhi tapu sites of significance, such as this one, were preserved appropriately for current and future generations.
"There are health and safety issues to consider, particularly around respecting these taonga by all who come across them," he said.
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