Incredible footage has emerged showing the extent of the damage on Milford Rd following significant torrential rain in the region.
The footage shows landslides and flooding on State Highway 94 - causing Milford Sound to be cut off.
More than a metre of rain has fallen in Milford Sound - which is under a state of emergency.
In two and a half days it's had the amount of rain Wellington would get in a whole year.
Evacuations from walking tracks are underway but MetService meteorologist Lewis Ferris says it will be a challenge.
Conditions are expected to ease in the region as the day goes on and the rain is now moving on to Westland.
Ferris told Newshub 300mm of rain is expected south of Hokitika on Tuesday.
"Most of that rain will be about the ranges but we still expect there to be large accumulations closer to the coast, possibly affecting the roads."
Meanwhile, helicopters are in the air rescuing about 100 people from walking tracks in the swamped Fiordland area.
But the evacuation of 195 tourists stuck in Milford Sound is on hold. Emergency Management Southland (EMS) says the forecasts look better for helicopters to rescue the tourists on Wednesday.
"Roads are closed throughout Southland and rivers are rising," EMS said on Facebook.