The West Coast has been thrashed by a combination of heavy swells and king tides, that have scoured away up to seven metres of land in some places.
Homes are under threat and residents are fearful of two more days of king tides.
Strong swells packed a punch along the coast and left homes in Ngakawau flooded in seawater.
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Local Sarah Godsiff feared for her life and home.
"When you see a wall of white coming towards you. Where do you run to because it's going to go on either side of the house so I just stood up on the back porch saying a few nice words," she said.
Kirsten Burdenkin said it was frightening.
"We were actually standing here and this huge wave just came over the sea wall and into her back garden. It's scary. It's really scary."
The coastline has been eroded up to seven metres in some areas, with driftwood carried 80m inland onto roads.
The situation is expected to worsen, with king tides every 12 hours for the next two days at least.
For Buller Mayor Garry Howard, it is the erosion of a historic landfill with four hectares of toxic rubbish that's keeping him at night.
"We've got old oil containers. This is an oil filter, oil bottle, and really it's just going to get worse," he said.
With each high tide, the old rubbish is loosening its hold.
"We know that there's industrial oil, paints, asbestos. It's an industrial dump. It's not your normal domestic dump."
The town has pleaded with central Government for a $600,000 brick seal wall.
They fear a similar situation to Fox where rubbish was strewn along a 100km of pristine beach.
"We see another Fox river happening here and no one seems to be interested in doing things and we think central Government should be stepping in to try and prevent another natural disaster like that," said Rob Burdenkin.
All residents can do is watch and wait for the next high tide.