As they barrelled towards a rock face, Brenda and Doug Weening thought it was just another trick their jet boat driver was using to scare them.
But in the last second before impact, the Canadian couple thought: "We're screwed".
"My last thought was, we're going to hit these rocks," Brenda said.
The Toronto-based commercial carrot-growers were on a Skippers Canyon Jet boat journey up the Skippers Canyon on Saturday - the first activity of their holiday around New Zealand.
Doug said the boat had just completed a U-turn and was headed back down the river when something strange happened.
"All of a sudden the driver couldn't steer, and he knew it. He was kicking something with his foot. And he had lost the reverse.
"Right up until the end we thought it was going to be a trick — he'll pull out, right?"
But the boat crashed head-on into a rock face, he said.
Brenda was thrown from her seat and was left clinging to the side of the boat with a broken leg.
"I was outside the boat. I don't remember how I got there. It all happened so fast," she said.
"Everyone was like scrambled eggs in a bowl. We all got moved around."
She said the driver moved the boat to a shallow area of the river and called emergency services.
"He's a fabulous guy. He was so helpful. He did all he could.
"It could have been much more traumatic but he kept everybody calm. He certainly kept it together."
All 10 people on board were flown from the scene by rescue helicopters. Nine people were hospitalised and two remained in hospital yesterday.
The Weenings also praised the staff at Skippers Canyon Jet, emergency services and the hospital.
"I ... want to thank everybody for the care that they've given, because it has been traumatic," Brenda said.
Doug said the jet boat firm had also kept constant communication with them, to make sure they were okay.
The couple sent their condolences to the family of the person killed in yesterday's separate jet boat crash during a race event near Hawea Flat.
"We feel sad for the family. We're thankful to be alive," Brenda said.
"It makes us realise it could have been a lot worse for us."
The couple had planned to holiday in Fiji after their NZ trip but Brenda will have surgery today to have a metal pin fixed to her leg, and they will return to Canada when she is released from Dunedin Hospital.
"It's certainly been a trip to remember. We've heard such good things about New Zealand and we'd still recommend it to everyone," she said.
"We're going to come back some time, but I don't think I'm going to go on a jet boat again."
Skippers Canyon Jet spokesman Gavin Larsen said the adventure company's operations remained suspended until further notice during Transport Accident Investigation Commission and Maritime NZ investigations.
He said he appreciated the positive comments from the couple about the care they had had after the accident.
However, he was unable to comment on potential causes of the incident until investigations were complete.
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