The bravery of a young woman swept away down the Waikato River after pulling her friend to safety has been praised by the Coroner investigating her death.
Rachael de Jong, 21, was swimming with six friends about 200m below the Aratiatia Dam, just north of Taupo, on Waitangi Day last year when the floodgates opened.
Within minutes, the tranquil water turned into a torrent.
Horrified tourists could do nothing but watch as the physiotherapy student and her friends were trapped on a rock and dived to safety, one-by-one, as the water rose around them.
Video footage shows Rachael, on safe ground, turn to help her last friend on the rock.
"It is clear that Rachael jumped into the water to try to help one of her party but tragically got swept away," Coroner Wallace Bain wrote in his findings released to the Weekend Herald.
"It is likely that but for this brave act, she might still be with us."
The dam floodgates are opened four times a day in summer for "tourist spills" - filling the rapids for visitors to see in a natural state - which are part of Mercury Energy's resource consent.
Sirens warn of the impending release of water, as well as signs in the official Department of Conservation carpark and tracks to the fenced viewing areas.
However, Rachael de Jong and her friends parked in a layby on the side of the road and walked down a well-worn, unofficial track to the river.
They would have walked past a warning sign, but it had been stolen two weeks before and not replaced.
While some of the group heard the sirens - and some knew that meant the dam was opening - Coroner Bain said it was obvious they were unaware of the true danger.
Some of the friends were taking "selfies" on a rock in the middle of the river.
"The photo shows the rapids in the background but clearly the group had no idea of what to expect and did not appreciate the risks, which if you had not been in the area before, is totally understandable," Coroner Bain wrote.
He compared the stretch of water as tranquil but quickly turning into "surf" or like a "washing machine, within a few minutes of the dam opening.
Since Rachael's death, DoC and Mercury Energy put up new warning signs and barriers to block the unofficial track, as well as removing a rope used to climb down to the water.
But Coroner Bain said other swimmers had been caught unawares in the river before and more could be done to stop another tragedy.
Mercury Energy wanted to ban swimming in the Aratiatia Rapids, but the Department of Conservation said there was no legal authority to stop people accessing public reserves.
The power company also believed a bylaw prohibits swimming within 200m of a hydro structure, enforceable by the Harbourmaster.
But the Waikato Regional Council said the bylaw was designed to regulate boating activity, not ban swimming in an area which boats cannot even access.
"It also seems clear to the Court that swimming in the area should be absolutely prohibited and that is simply demonstrated by the interviews [with the survivors]," wrote Coroner Bain.
"They are smart, intelligent young people but in essence had no idea of what to expect and on that basis were very much lulled into a false sense of security.
"If the group that were caught on this occasion were not able to sense the imminent danger with all that was then in place, then it is clearly possible that this could occur again, especially as it is a tourist area."
Coroner Bain "strongly" recommended Mercury, DoC and the WRC meet urgently to discuss how swimming could be banned, even if a law change was needed.
He also recommended Mercury consider how to visually monitor the water, perhaps by drone, before any water is released from the dam.
This was at the suggestion of Rachael's father Kevin de Jong, who said his family was pleased with the Coroner's report.
"This isn't about blaming anybody. It's about stopping it from happening again," Mr de Jong told the Weekend Herald in a special report about his daughter's death published today.
The feature story was researched through access to the Coroner's file including the witness statements of the six survivors of the tragedy, as well as video footage of the minutes leading up to Rachael's death.
"It felt like a washing machine, I had no control and I was running out of breath and I thought that was it, to be honest," one of the survivors told police.
Fraser Whineray, the chief executive of Mercury Energy, said the death of Rachael de Jong was a tragedy.
"Our thoughts remain with Rachael's family and friends".
Mercury supported the Coroner's key findings, said Whineray, in particular an absolute prohibition on being in the spillway.
The power company would continue working with DoC and the local councils to push for a ban.
He confirmed Mercury is considering whether physical checks of the spillway, perhaps involving technology, could make the spillway - which can open at any time due to the variable flow of the Waikato River - safer.
"However, a complete prohibition is the safest approach."
Allan Munn, the DoC operations director for the central North Island, said while the public cannot be banned from accessing public land, the conservation agency was keen to be part of discussions with Mercury Energy and the regional council about a swimming ban.
DoC had already taken the practical steps of putting up new barriers and signs on the informal track to the water, as well as more regular checks on whether warning signs were stolen or damaged.
"This was a unique, difficult, tragic set of circumstances which led to Rachael's death. We'll do whatever we can to help stop it happening again."
The Waikato Regional Council did not respond to a request for comment.