The two trampers missing in the Kahurangi National Park have been found alive.

Dion Reynolds and Jessica O'Connor, 23, went tramping in the Kahurangi National Park 18 days ago but failed to return when expected.

A St John spokeswoman said both only had minor injuries but an ambulance had met a helicopter to take them to Nelson hospital.

Reynold's work colleagues at Takaka's Roots Bar are overjoyed with the news. Owner Holly Osmond says the work group is over the moon about the amazing outcome.

Osmond and her chef Jose couldn't help themselves and had a shot of rum to celebrate the discovery.

Reynolds worked in the kitchen at Roots Bar over the summer and O'Connor worked at worked at Abel Tasman Kayaks.

Sightings of the pair before they set off on May 9 near the Anatori River suggested they were well-prepared for their trip, which was due to end on May 14.

Their parents and O'Connor's colleagues at Abel Tasman Kayaks were hopeful, saying O'Connor knew the area well and both were experienced in the outdoors.

The pair were due back from Kahurangi National Park on May 14 but have only just been found. (Photo / Supplied)

Staff at Abel Tasman Kayaks were excited at the news but the owner was unavailable for comment.

A large scale search effort for the pair included search teams aided by a dog and use of drones to create a heat map of the entire valley system.

Nelson Bays Area Commander Detective Inspector Paul Borrell told Stuff the pair "seemed to be in reasonably good health".

They were reportedly found just before 1pm.

Search team never gave up hope

Searching for the pair started last Tuesday, with good weather on the first few days. But over the weekend heavy rain had hampered the search, reducing the odds of the pair being found alive and well.

A Royal NZ Air Force NH90 helicopter has been helping search efforts over the past few days.

It was back there this morning, with the RNZAF sharing a photo of a crew of three on board - as well as a search dog all geared up and ready in a bright red vest.

The search for the pair resumed at first light this morning, police said.

Sergeant Malcolm York said the defence force was flying six teams into the area.

Today's search was to be centred around the Anatori River and the coastline, he said.

LandSAR NZ chief executive Carl McOnie said this morning that its team of volunteers were very skilled and was holding out hope of finding the pair.

"You never lose hope and you always have hope."

MORE TO COME