Before anyone stepped into Abbey Caves on the morning a school was due to visit, the danger was already building – in the sky, in the forecasts and in the weather warnings that grew more urgent by the hour.

However, an excursion for a group of Whangārei Boys’ High students that day continued.

During their visit, the water continued to surge and the group became caught in a rising torrent. Ultimately, it claimed the life of 15‑year‑old Karnin Petera.

Today, a school staff member who rushed to the scene described the horror he saw.

“When I saw the entrance of the cave, the water was two or three metres high,” the man, whose details are suppressed, said at the coronial inquest into the death of Petera.

“I had never seen anything like it before. It was simply beyond anything I could have ever imagined.”

He recalled seeing another staff member “shaking and crying”.

“He said one of the students, Karnin Petera, had gone missing,” the witness recalled.

The inquest, conducted by Coroner Alexander Ho in the Whangārei District Court, will examine how the risks of the excursion were identified, assessed and managed, before the trip and once the group was inside the caves.

Other focuses would be around adequate information about the dangers of entering the caves and where the responsibility lies to update weather information.

The inquest is being held before Coroner Alexander Ho. Photo / SouthlandTimes

“We need to all work together to try to prevent it from happening again,” Coroner Ho said yesterday, the first day of the inquest.

“We gather to understand what happened to Karnin.”

Heavy rain had soaked Whangārei for days before the May 9, 2023, school trip to Abbey Caves, a site long used for outdoor education, despite the caves having water levels that, even in normal conditions, can at times reach chest height.

That morning, a severe warning and thunder watch was issued about the same time Petera entered the caves with 16 classmates.

Once inside, water surged rapidly.

Students fought to escape, but the current pulled Petera down and trapped his foot between rocks.

A major search-and-rescue effort followed, with several students retrieved from surrounding rocks. It took 10 hours before specialist plumbers using underwater cameras located Petera’s body.

The school board was later prosecuted and ordered to pay more than $500,000 in reparations.

Severe weather warning

Yesterday, meteorologist Neal Osborne gave evidence at the inquest on the weather patterns in the days before May 9.

Five days earlier, the forecast for Northland, from the Kaipara to the cape, was marked with a severe outlook.

Osborne said that in the 72 hours before the trip, MetService upgraded the weather to a severe watch.

“This means everything is on track; we are expecting heavy rain to occur,” Osborne said.

The students went into Organ Cave in the Abbey Caves network on May 9, 2023.

Northland was under an orange watch for those 72 hours, with a heavy rain watch expected on the day of the trip from 6am to 9pm.

Osborne said MetService had guidance on its website clarifying what “orange” meant for the public.

“I would describe them as, you can undertake most activities as you normally would if it’s not particularly dangerous, but still be aware there’s going to be a risk,” Osborne said.

“Activities that are going to particularly put you in harm, by a river or a stream, these are the activities you would not want to take. It’s particularly risky for rivers or streams rising.”

A severe weather warning for Northland was issued on the MetService page on May 8 at 9.54am and 7.54pm.

Osborne said the data was tracking towards severe thunderstorms and heavy rain.

He clarified MetService was unable to pinpoint exactly where in Northland the thunder and heavy rain would land, but that it would likely occur somewhere.

“The model can only tell us the conditions are right for thunderstorms. It’s like having popcorn on the stove. For popcorn, you know they’re going to pop, you just don’t know which ones are going to pop first, some will pop, some probably won’t pop,” he said.

Osborne said the threshold for a heavy rain alert was to expect 15-25mm of rain per hour, during which “you would need your windscreen wiper going pretty quickly”.

A final severe warning and thunderstorm watch was issued at 9.15am, about the time the students entered the cave.

Under cross-examination, Osborne clarified that if the public is using the hourly rain watch data, there is a disclaimer that they should refer to the text, as that is the more accurate and accepted method. He said the disclaimer was not easy to read or interpret.

School management culture ‘tricky’

The staff involved in organising the trip have started giving evidence, with the first taking the stand today.

Their names and details are suppressed pending further directions from the coroner.

The inquest heard they had significant experience in caving and outdoor education and had previously organised hundreds of trips.

Whangārei Boys’ High had 80 field trips each year, timetabled for students to pass NCEA in outdoor education.

Rain poured over emergency services on the scene at Abbey Caves on May 9, 2023. Photo / NZME

As they kept an eye on the weather in the seven days before the trip, the original kayaking event was changed to abseiling, and then to caving.

The witness who took the stand today said it was changed because they knew it would be raining and they felt caving would be more appropriate, as it would keep the students out of the elements.

“The final decision rests with [suppressed]. There was no formal process to postpone or cancel trips or set what factors needed to be considered,” he said.

“I could always be overruled by anyone above..”

The required health and safety forms were sent to the heads of staff. However, the witness said he received no response and assumed everything was okay.

The man later said in evidence that he felt unsupported by school leaders and isolated.

He said the culture at Whangārei Boys’ High was “tricky” and although there was an open-door policy with the principal, if things were raised, they were not dealt with.

He believed health and safety oversight should sit with someone not influenced by curriculum pressures who could provide an independent review and final sign‑off.

The staff organisers were watching the MetService hourly rain radar and interpreted the data that heavy rain would hit about 2pm on the day of the trip.

“I had confidence in the images.”

A decision was made the day before to bring the trip forward so the students would be out of the caves by noon.

While the witness was not at the caves, he recalled that “at some point it started raining but it wasn’t a deluge”.

At 10.15am, he received a phone call that the boys were stuck in the cave.

He immediately went to the scene and said the water was 2-3m high when he got to the entrance of Organ Cave.

When asked whether he believed the staff member at the cave made the right decision to evacuate the boys, the man said he had full trust in that person’s knowledge and decision.

“If that group had got to the water five minutes earlier, they would have gone through and exited normally. If they had got there five minutes later, he would have had to stay in the back of the cave,” he said.

“They didn’t have food for the next day, they would have got cold, the situation would have been very different five minutes either way from what I read in his statement.

“I trusted him and he had a lot of experience and I imagine at the time when he got to the water, he thought it was safe.”

The man said that after hearing Osborne’s evidence from MetService, there were things he was not aware of when reading the data before the trip.

One of his recommendations to the coroner was that all outdoor education facilitators sit a course with MetService to understand weather map reading.

He believed in the values outdoor education provided for youth, but said it was not worth doing if it came with risks.

“I was absolutely devastated by what happened and I still think of what happened on May 9 every day.

“I cannot imagine what Karnin’s parents and family have gone through, and are going through and will go through for the rest of their lives.

“I continue to extend my very sincere and profound condolences. I carry Karnin’s death with me, and the traumatic experience the students and instructors had, every day.

“I wish certain events had not happened. If I could go back and make different decisions, of course, I would cancel the trip, but that is said with the immense benefit of hindsight.”

Shannon Pitman is a Whangārei-based reporter for Open Justice covering courts in the Te Tai Tokerau region. She is of Ngāpuhi/ Ngāti Pūkenga descent and has worked in digital media for the past five years. She joined NZME in 2023.