Fatal trip 'chance to be family'

"I've screwed up - my wife's dead and the kids are on a ledge."

That was how Peter O'Brien summoned help after his futile attempts to save his wife deep inside a cold, wet cave.

Noelleen Merle O'Brien succumbed to hypothermia during a family outing to Cave Stream, near Porters Pass, a week-and-a-half ago.

Their children, Jade, 13, and Julian, 8, were plucked by rescuers from a narrow ledge.

A short distance downstream, on her back with water rushing over her face, lay Mrs O'Brien.

At a preliminary inquest yesterday, Christchurch coroner Richard McElrea was told of an unwitting domino effect that ended with what he ruled to be death by misadventure.

Mrs O'Brien, 40, was especially vulnerable to hypothermia. She weighed just 46kg, smoked heavily, and suffered severe asthma and acute emphysema.

Mr McElrea took the unusual step of convening an early hearing to quell "public conjecture" surrounding the tragedy.

The O'Briens' marriage had foundered about seven months ago and they separated in March. However, they had kept in regular contact and, according to their pastor, were working towards a reconciliation.

"There was no violence or animosity in our break-up. We had issues but it wasn't a major problem," Mr O'Brien told police after his wife's death.

In his statement, read to the court, Mr O'Brien said he had the weekend offer of a home at Castle Hill, and initially planned to take just his son.

"We had heard about Cave Stream [near Castle Hill] and thought that would be pretty exciting," Mr O'Brien said.

Then his wife and daughter decided to go too. It was an opportunity to be a family again.

Mr O'Brien said his confidence in tackling the cave with children was boosted by his understanding that a friend had taken a 5-year-old through. He learned later they went only into its entrance, took photos and left.

The day before the tragedy, the O'Briens checked out advisory signs at Cave Stream. Wool or propylene clothes, a warm hat and gloves, secure footwear such as running shoes, and one torch per person are recommended.

Mrs O'Brien was ill-prepared. She entered the cave wearing two long-sleeved cotton tops, green trackpants and borrowed oversized sandshoes.

"You're brave," outdoor safety expert Ray Goldring, working on a nearby track, told the family, adding that the cave was cold at this time of year.

Mr O'Brien decided to plough on, believing he and his family were adequately clothed.

"Now ... I wouldn't go in without a wetsuit," he told the inquest.

"It was cold, but I'm used to the cold. I'm a diver. I'm [aware of] cold on the legs, but after a while it goes."

Mrs O'Brien's clothing provided little insulation against a water temperature of 5.5C. After she became soaked from wading through a waist-deep pool, then slithering, with her husband's help, up a small waterfall, her body heat rapidly drained away.

She lost her shoes, and Mr O'Brien dropped one of their two torches. He decided they should turn back when confronted by a second, steeper waterfall.

"Noelleen started saying things like 'keep on talking Pete ... then started slowing down," Mr O'Brien said in his police statement.

He recognised his wife was in the grip of hypothermia.

"Noelleen was exhibiting signs of slurring, slow speech, slow movements, she seemed to have lost touch with what we were doing. She didn't recognise the need to get out of the cave ... I knew we were in a crisis."

By this time, the other torch had failed. Mr O'Brien elected to put his wife and children on a ledge and go for help. "I got about 10ft down, hugging the wall. The kids then yell out 'Mum has fallen in the water.' I found her and picked her up out of the water. She was soaked.

"I found a rock, and sat on it. I had Noelleen in my lap and was trying to warm her up. She was murmuring and talking a bit."

Mr O'Brien said his wife slipped out of his grasp, back into the water, before he managed to get her up onto the ledge again.

"I took my tracksuit top and sort of put it over [her] to try and breathe some heat into her. She then went stiff and clenched her teeth. She then relaxed again. I carried on trying to warm her up again. She then had a second seizure, when she went stiff again."

Mrs O'Brien's body went limp.

"I knew she was dying, or was already dead. I reassured the kids that Mum was just asleep.

"I tried mouth-to-mouth for a while, but I knew it wasn't going to work."

Through the dark, Mr O'Brien told his frightened children to stay put while he went for help.

Stumbling out of the cave he spotted Mr Goldring: "I've screwed up," he said. "My wife's dead and the kids are on a ledge."

As the alarm was raised and rescuers scrambled to respond, Mr O'Brien went back for his family with Martin Gaynor, who happened to be heading for the 360m limestone cave walk.

Mrs O'Brien was found almost completely naked. The cotton tops were over her head, the tracksuit pants dangling on her right ankle.

The coroner said her clothes had been dislodged by the force of the water. Her son had lost his pants in the current, too.

Julian and Jade were found crouching where they had been left, on a ledge about 30m from their mother's body.

Mr O'Brien yesterday thanked Mr Goldring and other rescuers for preventing what could have been an even bigger tragedy.

The inquest was adjourned to allow evidence to be gathered on safety issues, including whether Cave Stream should be off limits in winter.

- NZPA