Torrential downpours on the South Island's West Coast have led to slips and road and school closures, with some sites copping nearly half a metre of rain since Sunday.
A man from the United Kingdom travelling New Zealand with his partner will be stuck in a Franz Josef campground overnight due to flooding.
Oliver Harcus told the Herald a lot of foreign travellers are currently staying at the campground, many of whom are unaware they are trapped.
Earlier this evening, the Waiho Bridge was taken out by the rising and rough floodwaters of the Waiho River near Franz Josef.
Flooding hasn't only been restricted to rivers, surface flooding has also resulted in road and school closures throughout the region.
"I've never really seen the power of the water like it has been today ... this is another level," Harcus said of the wild weather.
Rain had fallen consistently throughout the day, he said, with waterfalls forming off hills on the roadside and creeks swelling beside them.
The bridge over the Waiho River at Franz Josef is washed away at 4:30pm. Photo / Supplied
Harcus and his partner have been living in Wellington so they were used to rain and wind, however, they found the drive from Hokitika scary due to the conditions.
"The roads that we came in on, they're pretty treacherous all the way down," he said.
"There were definitely roads that would not be driveable now, they were just drivable when we passed.
"There were points that we were very, very lucky that we weren't caught in a smaller township than we're already in."
The NZ Transport Agency reports State Highway 6 has been closed in numerous locations between Makarora near Wanaka and Hokitika on the West Coast.
Police are advising members of the public to avoid travelling due to the weather throughout the night.
The Waiho Bridge washed away in the river. Photo / Brett Grant
Damien O'Connor, MP for West Coast-Tasman, was at the Westland District Council emergency centre and said everyone "seems to be safe through the night".
"The road is closed so people will be staying put wherever they are between [Hokitika] and Haast," O'Connor told Newstalk ZB.
"Generally speaking, the people here are confident that all that can be done is being done at the moment."
Harcus is expecting to be stuck in Franz Josef for at least another 12 hours, with rain still falling and surface flooding continuing.
He and his partner are travelling in a van, so can avoid pitching a tent, however, there are numerous other campers with tents only, he said.
Earlier today, the Waiho River was running at a level of 7.6m but had dropped back 0.7m from its peak since.
