Queen Charlotte Track is being widened to make it safer for trampers and mountainbikers to share.
Workmen are making the track 30 centimetres wider and creating a benched surface between Resolution Bay and Furneaux Lodge at Endeavour Inlet.
The upgrade will turn the popular tramping track into a dual use track for mountainbikers and walkers year round with the exception of the Ship Cove-Kenepuru Saddle section, which is closed to mountainbikers between the peak times of December and February each year.
Department of Conservation services ranger Leanne Flynn said the work would create a consistent width along the track that was safe for trampers and bikers to coexist.
The new surface will help improve the ride, possibly forcing riders to slow down at certain trouble spots, she said.
"We manage the safety of the track users by closing the Ship Cove-Kenepuru Saddle section at the height of the season due to it being so busy," she said. "We will always get those bikers who will go too fast but we keep a register of complaints that we are made aware of with very few complaints found. Bikers know how to get around trampers safely."
Workers have upgraded 1.5 kilometres of track so far, and will work on a 3km section near Furneaux Lodge over the next four weeks. A 3-tonne digger was barged to Resolution Bay so a ranger could clear rubble created from blasting work.
Another ranger, who is a former stonemason, has been strengthening culverts and laying new culverts to replace bridges.
DOC has provided on average $50,000 in capital funding each year over the past three years to upgrade sections of the track.
The Resolution Bay to Furneaux Lodge upgrade is due to be completed in six to eight weeks. It remains open to the public while work continues.
Ms Flynn said this part of the track attracted 10,500 walkers last year. "This section is a very popular day walk as people get dropped at Ship Cove and walk to Furneaux Lodge where they get picked up at the end of the day."
Last year the track was named New Zealand's 21st Great Ride on the Nga Haerenga New Zealand Cycle Trail.
"We have been upgrading the Queen Charlotte Track before it was ever recognised as part of this trail," Ms Flynn said.
"But this recognition as well as being part of the Te Araroa Trail helps with the bids for capital funding in future years for upgrade work just like this."
- The Marlborough Express