Whole trees, mud and silt are blanketing parts of the Nelson and Tasman regions, with despairing locals wondering how long it will take to repair the damage.
Cyclone Gita's aftermath has created power outages, blocked roads and left water cut off in some places.
One of the areas impacted is Marahau, where forestry logs have been swept downstream and taken out cabins and homes.
While the waters have receded, they've left behind a foot of thick mud across homes, gardens and paddocks.
Philip Reed, 54, was helping neighbours with the cleanup, and had mud up to his knees and elbows.
"I was here overnight, and I saw that entire gully just pop. Trees, whole bits of hillside were going past.
"It washed one guy's car down the river.
"It's probably 50 years since I've seen this. It's just devastating. We don't quite know what we're going to do, but that's just the way it is I suppose.
Reed said the road was blocked, and he expected it would be weeks before it would be fixed.
He planned to walk and hitch-hike into town for supplies later.
"Even the concrete bridges are underwater, all our water supplies are absolutely gone, no tanks left in the gullies, no water pipes.
"My uncle down the road has massive, big pine logs all over his paddocks. It's pretty devastating."
Reed said they needed the roads cleared as soon as possible, as well as water supplies fixed.
Adam Mills, 50, has lost the cabin where his family would stay on hunting trips, hosting barbecues for friends and enjoying being cut off from the world.
As well as the cabin, he'd lost stock and beehives.
He became emotional as he talked about the memories that had been swept away when the cabin was destroyed by the burst river.
"It's hard, but I guess that's the way nature is," he said.
"We would come and have barbecues here, get on the piss. My son, he's 2. Family and friends here.
"It's had about half a metre of water through everything. I just knew it would be bad, and I told myself, it's just land and we'll have to rebuild."
Cyclone Gita is the third severe weather event in the Nelson region in the past fortnight.
Mills said he needed this to be the last one.
"As long as it doesn't happen again, we can be all right. Each time the river blows out more, and becomes worse.
"That's my fear. We need to get some banks up and quickly, before we get another deluge, otherwise we are in trouble."
Sean Llewellyn, 43, said the local river had become bigger than he'd seen in the 15 years he'd lived there.
"On any big storm you see the river coming up, but it breached in several places where I've never seen it breach before.
"I guess I'll have to bicycle and hitch-hike for a while now, because I have to get to work.
"Everything is going to take a lot longer. Everyone around here just has no access to go anywhere by vehicle, but you've got to get to work, you've got to get food."
The after effects of the storm will take at least days, and possibly weeks to fix.
Residents in Golden Bay are being warned they'll be cut off for several more days, but that food will be shipped in. Nelson Civil Defence has warned locals not to panic buy food or petrol.
The loss of power in Kaiteriteri led to sewage overflows, so swimming should be avoided in the area.
Water supply at Dovedale isn't working, so residents will need to rely on stored water for the time being.