The weather bomb that hit the South Island's West Coast this weekend - a one-in-50-year storm - closed all roads into the Buller, prompted MetService to issue a rare "red warning" and regional emergency management to declare a state of emergency.
The NZ Transport Agency said today towns including Westport, Nelson, Tākaka, Collingwood and Murchison in Tasman District were affected.
The entire town of Spring Creek, near Blenheim, has asked all of its over 400 residents to evacuate.
“Hanmer Springs in Canterbury currently has no access from the state highway to the south, however that is expected to be resolved by midday today with crews clearing slips now,” says Tresca Forrester, Journey Manager for Waka Kotahi NZ Transport Agency.
Ms Forrester said people should avoid driving in these areas today, particularly given more rain is falling in Nelson and Marlborough and more roads may well close as river levels and rain peaks later.
“Our crews are working as hard as they can but these slips and debris will take time to clean up and flood waters take time to subside. In some places we have to wait until the river levels have subsided to get access to the slips. Please do not drive if you do not have to or delay your journey until later today and check highways then.”
And the country's weather authority has issued a spate of weather warnings for the country - including a North Island-wide strong wind warning.
Buller mayor Jamie Cleine said the river had swollen to an "extremely high" 11.3 metres but hadn't burst its banks.
"[It's] at least a 50-year flood event," he said.
There were nerves around the 3.30am high tide with a tidal surge predicted - but both had passed without significant impact, Cleine said.
Emergency response personnel were waiting until daylight to get a better idea of the situation - including when the currently closed roads into the region could be reopened.
State Highway 6 from Westport to Rapahoe and SH73 from Arthurs Pass to Jackons were both closed due to slips.
SH7 from Ikamatua to Stillwater is closed due to flooding, while flooding and multiple slips have closed SH65 from O'Sullivans Bridge to Shenandoah, and SH60 from Collingwood to Riwaka.
More than 700 people in Buller were evacuated from low-lying areas to four evacuation centres in the district.Evacuated residents were this morning asked to "stay away" from their homes, as the risk of moving floodwaters remained.
West Coast Emergency Management this morning said there was still a large amount of water in the ranges that needed to make its way down the Buller River.
"We know you are keen to get home. We ask people to stay away from their homes while the risk remains. We will let you know when it is safe to return home."
Last night the Army deployed 14 personnel and seven vehicles from Burnham Military Camp in Canterbury to assist with evacuations following flooding.
When Cleine visited the centres this morning, people were sitting around playing cards - waiting for more information on the situation.
"We're just reinforcing that message that even though we're really happy with how things are going, we just need another couple of hours to make sure the river has settled down."
In Westport, Fire and Emergency received 12 calls about trees that had blown down.
Shift manager Lyn Crosson said fire crews didn't attend some of those because the council attended instead.
- additional reporting ODT
