Ms De Jong’s brother has penned a moving tribute to his “perfect” sister on Facebook.
“Yesterday I lost one of the most important people in my life, my wonderful sister,” he wrote. “Not only was she an inspiration to us all, she was my best friend, and the most perfect sister I could ever have asked for.
“I can’t even begin to describe how much I’m going to miss you, and how incredibly unfair it is that you have been taken far, far too soon,” he wrote. “You never spoke a bad word of anyone, and you had such an infectious smile that could cheer anyone up.
“There’s not enough words in the world I could use to describe you. I love you so much Rachael, rest easy.”
The floodgates Aratiatia Dam are opened several times a day, with a five-minute warning and ‘no swimming’ signs altering people to the danger, reports the NZ Herald.
"Our sincere thoughts go out to the family and friends of the person who has passed and to those who are recovering at the local hospital and who will be traumatised," said Mercury Energy chief executive Fraser Whineray.
The company has confirmed the siren was definitely working when the accident occurred, but say they will be reviewing safety procedures.
"We've been running these spills for years, in fact they are a condition of our consent because it is part of the tourism environment there," Whineray continued.
"But this is a very concerning event and we will be reviewing all of the many measures we've put in place to try and see what else we can do to see if we can reduce risk as much as we can to try and prevent something like this from happening again."