As many as 400 people offered to help clean up damage in Nelson from last week's storm.
The city council and community organisations have formed a Facebook group to connect volunteers with those needing support.
Council community partnerships advisor Bill Huppler expects the group will be a key part of the city's long-term recovery.
More than a hundred houses in Nelson have been deemed too unsafe to live in, and hundreds of others are damaged by slips and flooding.
Huppler said people had already offered accommodation, community meals, manual labour and equipment for those in need of them.
The offers covered a wide range, from people offering to roll up their sleeves and muck in: "Like providing food for people or someone says I've got a spade and a couple of spare hours and they want to help," he said.
To much larger offers: "Amazing organisations and companies that are talking about providing diggers and other more commercial plant."
Huppler said it had been overwhelming to see the community respond so generously.
"I think it will be sustainable... there's an overwhelming amount of people that do want to help - probably more help than there is actual help needed at the moment.
"But I'm sure that as we shift towards more of a recovery phase, that more opportunities for help and support will arise for people."
RNZ
