Bringing tourists, many who have never been on a river before, through powerful rapids and violently fast currents is a risky business.
Dale Gardiner and his wife, Anne, of Queenstown, were among the first to take that risk.
"There is always going to be an element of risk to life, especially with grade-five rapids.
Grade six is unrunnable so it's the maximum you can do.
But that's what gives you a buzz," he said.
The Gardiners moved to Queenstown from Auckland in 1971, when Dale was 22.
The couple started Dane's Back Country, running 4WD trips to areas like the Rees Valley and Skippers Canyon in 1974.
Kon Tiki Raft Trips began rafting trips on the Shotover River the same year.
A year later, the Gardiners set up The Original White Water Rafting Company, beginning with rafting trips in the Upper Skippers Canyon.
Safety requirements included carrying anchors, bells and a bucket of sand for fires.
"It was stupid.
Legislation was so out of step with operators.
What we needed were throw bags - which are still used today for rescuing people - and knives for cutting rope," he said.
Crotch straps for life jackets were invaluable to stop the jackets slipping over people's heads.
"I don't know why they are not still used today," he said.
Neither helmets nor wetsuits were used in the beginning.
"But as we got going, more safety techniques were introduced by us," he said.
He had two fatalities on his trips in the 12 years of operation, one from a heart attack, the other from drowning.
"It was very hard.
We had to talk to the families about how their father or husband died," he said.
The drowning victim had hit his forehead and drowned after being knocked unconscious, despite wearing a helmet.
"We had guides stationed with throw bags to rescue people downstream, but he floated down past the guides.
We did recover his body, but it took four hours for the emergency services to send a helicopter.
It wouldn't have saved him, but after that we started organising our own rescue helicopters," he said.
His first raft was an Avon Adventurer Raft imported from the United Kingdom.
He used his New Zealand Forest Service deer culler mates as guinea pigs for his first trip.
"The boat was almost destroyed, probably because we all thought we were captains but didn't know what we were doing," he said.
"We took a six pack of beer but didn't drink it because we were too busy trying not to hit rocks.
We thought we were going to cruise down the river with a few cold beers, but it wasn't quite like that," Mr Gardiner said.
In 1976, he employed the help of a professional river rafting guide from the United States, Mark Pickering.
"He never hit a rock, so I employed him and he trained me.
The government helped US professional river guides to train New Zealanders.
Within five or six years, Kiwis were training Kiwis.
It was fantastic," he said.
The first commercial trips were in the Upper Skippers Canyon's grade-three rapids; a year later they expanded into the Lower Skippers Canyon grade-five rapids and the grade-four Kawarau River.
As one of the first to navigate the rapids, he had the pleasure of naming some, including the Cascade Rapids and the Mother Rapids.
The Mother Rapids have interesting names including Pinball, Toilet, Squeeze and Jaws.
Jaws got its name after a bus driver fell out of the raft in the rapids and lost his false teeth.
On the Kawarau River, he named the Dog Leg and the Do Little Do Nothing rapids, which appeared through rockfall or earthquakes during the time he was working on the river.
He employed skilled river guides to bring up to 12 boats at a time down the river.
He was the first to run trips on the "remote and wild" Lands-borough River on the West Coast, which had grade-five rapids.
He would first fly over the rivers in a helicopter and mark out any obstacles on a map and check at the start of every season for new rapids.
In the beginning, the guides used oars, then came paddles for passengers to use.
The rafts also went from having a solid floor to self-baling.
"It was exciting, especially knowing we were the first going down some of the rivers on a raft.
That was a big buzz," he said.
The Gardiners sold the business in 1987.
"After 17 years in tourism, I wanted a change, so I pursued my photography and I'm still doing that full time," he said.
He also works as a locations scout for television commercials and films around New Zealand, including The Lovely Bones, for which he had to find "heaven on earth".
Having explored New Zealand's back country extensively, he said narrowing his choice down was difficult.
His personal heaven on earth is rafting on the Shotover River - a risk he has never regretted taking.
