It's now a race against time on the West Coast as bad weather threatens the clean-up of tonnes of rubbish along the coastline.
Two weeks ago heavy rain flooded the old Fox Glacier landfill, spewing rubbish into waterways that went to the sea. Fifty kilometres of pristine coastline was inundated with the rubbish.
Today was fine in the region, but MetService predicts 100 millimetres of rain in a space of 12 to 24 hours from tomorrow night.
Authorities say they can't afford to have their clean-up efforts hampered now, and they're also worried any rubbish underneath the sea floor and riverbeds could be stirred up.
Today saw the largest volunteer response yet, with 49 people flown in by helicopter to collect rubbish.
Volunteer coordinator Mike Bilodeau said there's "lots of plastic bags - it's so bad for plastic bags - car tyres, oil containers and bottle caps, really bad for straws and utensils, just everything".
Westland Mayor Bruce Smith said the volunteers include "backpackers, grandmothers, grandfathers, guys who've got jobs who've just dropped their jobs and they're out here".
Three incident response managers from Maritime New Zealand were also flown in to offer their expertise.
The Westland District Council is currently footing the bill to get people to the scene by helicopter.
"In terms of bringing them in that's primarily into areas where we do not have alternative access either through private farms and properties with tracks [that] enable safe access to the river, and also parts of our coast that are just not accessible given the terrain," said Te Aroha Cook, the council's recovery manager.
Mayor Bruce Smith estimates the clean up will cost millions of dollars.
"Within two or three weeks it'll be tidy. However, I reckon it'll go for three or four months. Every time there's a decent flood we'll be into it again," he said.
And there's growing concern over the impact on marine wildlife.
"We're finding penguin prints walking through loads of rubbish. It's just really sad. People are seeing oyster catchers eating bits of plastic, white heron in the white heron sanctuary sitting on plastic bags and rubbish," Mr Bilodeau said.
"And we also don't know what's leaching out of everything."
Mr Smith says it's an environmental disaster that no one saw coming and was unpreventable.
He said the dump commissioned in about 1945, decommissioned in, he thinks, the 1980's, and it was about 60 metres away from the river.
It's a heartbreaking eco-disaster which coasters never want to see again.
Local authorities are looking at what emergency funding may be available from the Government to bolster their resources and emergency help for the clean up.
In the meantime, 24 members of the Student Volunteer Army are heading over from Christchurch to be in place when the wet weather is due to hit on Wednesday and they'll stay until the weekend.