With the only bridge south washed out and slips blocking the roads further north travellers in the tourist mecca of Franz Josef are scrambling to come up with new itineraries.
United Kingdom citizens Oliver Harcus and his partner were two of 450 tourists stuck in Franz Josef overnight due to the flooding and road closures.
He and his partner were travelling in a van so kept relatively dry through the night at the campground, however, there were numerous other campers with tents only, he said.
They had planned to spend a few days in Franz Josef, visiting the glacier across the Waiho River before moving onto the Fox Glacier and through Haast Pass to Wanaka, but would now need to reassess their plans.
Yesterday evening the Waiho Bridge just south of the town was taken out by the rising and rough floodwaters, and a state of emergency was declared for the district shortly before 6pm.
Tourists were kept in the small West Coast town yesterday with treacherous road conditions also north to Hokitika.
Further north Arthur's Pass remained blocked today by two slips, with updates due at midday, leaving the only way out of the West Coast region several hours' drive north and through the Lewis Pass.
With many travellers planning to head south from Franz Josef to the Wanaka/Queenstown area, today they would have to make new plans.
"We are lucky as we have a bit of time, we are here on a one year visa, and have about five months left," Harcus said.
"Some others have quite short timeframes, and some people could be missing their flights."
More than a metre of rain
The Westland district has been inundated with what Mayor Bruce Smith called a "100-year event".
NIWA has reported since 3pm Sunday some high elevation areas had received more than 1m of rain.
The Cropp River station had recorded 1096mm, just below Auckland's average annual rainfall of about 1200mm.
Also in the Southern Alps, Mueller Hut recorded 683.6mm, Ivory Glacier, 636mm, Haast River 578.5mm, Mt Cook 533.3mm and Mt Philistine 489mm.
Near the coast many stations had received about 200mm of rain.
Flooding hasn't only been restricted to rivers, surface flooding has also resulted in road and school closures throughout the region.
Harcus and his partner have been living in Wellington so said they were used to rain and wind, however, they found the drive from Hokitika scary due to the conditions.
Rain had fallen constantly yesterday, he said, with waterfalls forming off hills on the roadside and creeks swelling beside them.
"The roads that we came in on, they're pretty treacherous all the way down.
"There were definitely roads that would not be driveable now, they were just driveable 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."
Harcus said they had heard the West Coast was infamous for its wild weather, but this was "another level".
"I've never really seen the power of the water ... ," Harcus said.
"Coming from the United Kingdom we deal with a fair amount of rain, but the amount of ground water was just mental. In hindsight it was a bit scary, seeing raging creeks and rivers, and a bridge washed out. It doesn't happen very often."
State of emergency still in force
Westland District Mayor Bruce Smith said he expected the state of emergency to be lifted "today or tomorrow".
"The big focus now is working out the immediate things to tend to. The Waiho Bridge is our lifeline, for the 1.1 million tourists we get annually."
The NZ Transport Agency had told him it could be fixed in 14 days, but he had other advice it could be restored in 10.
"I'd be very disappointed if it was not up and running in 14 days."
There were 450 tourists kept in Franz Josef overnight, and they would be allowed to travel north later today.
"We could have released them last night back to Hokitika but there was a risk factor," Smith said.
With the Waiho Bridge out of action the only way south now was "by helicopter".
"It is really unusual to get a 100-year event, right across Westland. Normally it is concentrated in one place, but this was right across, so it has been a really big event," the mayor said.
"The Haast River was at the highest level it has ever been. We had 800mm of rain, I can't remember there ever being that much in my life."
Smith said they were lucky the rivers held their banks.
"In the Haast River it was lapping at the rock walls, flowing over, if there had been any structural problems there could have been some major issues. Additional protection at Franz Josef held too."
A Community Information Centre to assist with displaced people would be set up in the Hokitika iSite, on the corner of Weld St and Railway Tce, Hokitika from 8.30 am.
Those who required assistance could contact 0800 474 834.
Wild weather heading north
MetService meteorologist Kyle Lee said the front that caused major flooding in Westland was moving north today.
Most stations along the coast had recorded just under 200mm since the rain event started on late Sunday/Monday, with stations inland getting well above 200mm, and one station even recording around 1000mm.
Heavy rain warnings were expected to ease this morning, with Buller currently receiving its heaviest rain until 11am.
Westland would see the rain ease to some scattered showers this morning with the front and heaviest rain travelling northwards towards central New Zealand this afternoon and the central North Island tonight.
As the front approached the North Island, Wellington and Wairarapa had strong wind warnings in force until 2pm this afternoon.