The heavy rain that has been inundating the top of the South Island has eased but a civil emergency remains in place in the region.
Two days of heavy rain has caused widepread flooding and at least 170 slips in the Nelson and Tasman regions, blocking roads and cutting off townships.
Twenty-four roads remain closed, with others open only to local traffic.
Civil Defence says police evacuated about 50 houses and the occupants of about 100 more left their homes voluntarily.
People in Pohara and Dovedale have been advised to boil any water before they drink it.
A state of emergency was declared on Wednesday and civil defence says it will remain in force until Monday.
In Ligar Bay, Neil Batten told Checkpoint he and his wife Liz had only seconds to flee their home and at least 10 homes were hit by the wall of logs and silt.
Welfare centres have been set up at the Suburban Club in Nelson and the Newlife Church in Richmond. If people require welfare assistance or sandbags, please contact your respective council call centre: Tasman District Council 03 543 8400 Nelson City Council 03 546 0200.
Tasman mayor Richard Kempthorne says it is remarkable that nobody has been hurt, given the damage caused by the region's worst rainfalls in recent history.
The torrential rain began on Tuesday and continued for most of Thursday.
At least 500 millimetres fell in some coastal areas, making it one of the worst rainstorms in the region in recent history.
The Nelson Tasman civil defence's public information manager Chris Choat says the records broken include Takaka, where 423 millimetres in 24 hours was more than double the previous record, set 50 years ago.
In Nelson, 330 millimetres fell in 24 hours, exceeding the previous record of 273 millimetres.
Civil defence warns more slips can be expected as the saturated land erodes.
Warning to stay off roads
Police in Nelson are warning motorists to stay off the region's roads.
They say they have a simple message: if you don't need to use the roads, don't.
A spokesperson says motorists are taking unnecessary risks given the conditions and "rubberneckers" have caused further problems for already congested traffic by driving to see swollen rivers.
In Nelson city, some roads have re-opened but one of the main access roads, Wakefield Quay and Rocks Road remains closed.
All roads north of Pohara are impassable.
The Takaka/Golden Bay road, State Highway 60, remains cut on the Collingwood side by a 50 metres slip at Bird's Hill. That is expected to take three days to clear.
The Army has been asked to provide two UNIMOG vehicles and drivers to help in Golden Bay.