Torrential rain in the top of the South Island has severely damaged parts of the Heaphy Track, destroying three bridges.
The 78-kilometre track remains closed until Saturday, and the Department of Conservation (DOC) will update people before then about when it might be possible to reopen it.
DOC Buller operations manager Suvi Van Smit said rangers flew by helicopter over the track yesterday to start assessing the damage.
The area between the Mackay and Heaphy huts was the worst affected.
The flyover indicated the 150-metre-long suspension bridge over the Heaphy River was damaged beyond repair. It is less than 10 years old.
The 70-metre Gunner River bridge is also damaged with snapped sway cables. It appeared the river had washed over the bridge deck.
Rangers were at the bridge today securing what they could before the heavy rain set in again and potentially did more damage, Van Smit said.
A smaller bridge at Pitt Creek which was built last year, had also been washed away.
A more detailed assessment and repairs will be carried out when this next bout of heavy rain is over.
Van Smit said the huts had made it through unscathed, but the water supply at Heaphy Hut was damaged. There is also a slip on the coastal section between Kohaihai and the Heaphy Hut.
MetService has an Orange rain warning in place for Buller, which ends at 10am tomorrow.
The Paparoa Track reopened on 9 January, with the only damage a slip on the Pororari River section.
Walkers can use the Punakaiki end of the Paparoa Track via Waikori Road until the Pororari River Track reopens.