Nearly 90 homes in the West Coast's Buller District have been severely or completely ruined by the flooding over the weekend.
The mayor is worried hundreds of houses may need to be demolished while more than 150 people are still in evacuation centres.
Westport resident Alison Fox's house was particularly affected by the flooding. She's now waiting for an inspector to decide just how bad it is.
"I'm picking we'll probably be a red sticker," she said.
A red sticker means their home is uninhabitable. So far, 89 red stickers have been issued - including for Corey Sutherland's home. He told Newshub "nothing survived".
More than 2500 houses have now been assessed by the council, of which 400 have moderate damage. Buller District Mayor Jamie Cleine is worried the number of homes needing to be demolished will rise.
"It's looking like it's going to be probably hundreds... it's too early to say, but it's going to be significant," he said.
Climate expert Luke Harrington is warning these significant rain events will increase.
"Roughly a doubling in the likelihood of these events happening in a given year."
At the weekend, the Buller River peaked at 12.7 metres - blowing all records out of the water. Meanwhile, Marlborough recorded its worst flooding in nearly 40 years and Wellington took a hammering too.
"It has been made more intense because of climate change," Harrington said.
Massey University Professor Bruce Glavovic says we need to plan for it.
"In the most extreme circumstances managed retreat is a necessary reality... we're going to see lives lost unless serious action is taken."
Mayor Cleine says they'll be having those discussions with the Government - discussions which could have an impact on these local communities.