Department of Conservation senior ranger Annette Grieve said on Tuesday the need for the upgrade had been brought on by the huge increase in foot traffic in recent years.
In the 2017-18 year 120,000 people walked the track, compared with 80,000 10 years ago and just 21,000 in the 2004-05 year.
Ms Grieve said two parts of the track on the steep western face would be realigned once agreement had been reached with the owners of the private land the track passes through.
"A section of the track is not on Doc land.
"Just as soon as that approval comes through we will have that realignment done."
The work would make it easier to maintain a good track surface, she said.
"It used to be a bit on the steep side but you didn't have so much traffic so it didn't get worn down or eroded so quickly.
"Now, because it gets worn down so quickly, we just can't keep the gravel up to it."
The work is scheduled for this year, with funding also being sought for improvements to other parts of the track in the 2018-19 year.Ms Grieve could not say what the cost would be.
The track was last upgraded about five years ago.
Improvements are also planned for the car park at the start of the track in the 2018-19 season.
Ms Grieve said Doc "continued to be disappointed" at the amount of "dog waste" along the Mt Iron track including "dog bags not being disposed of appropriately".
"There's nothing worse than walking along the track and seeing little blue plastic bags left on the side of the track."
Ms Grieve said Doc did not want to get to the stage of having to ban dogs from the area.
