He said some of the dead students had just been to a leadership course where they were asked who would want to be head prefect at the Christian school.
"They all put their hands up. That is the sort of quality of people we are talking here."
He said the teacher who drowned with the students had joined the school this year.
"He has been working in our sports and Christian living section. He has just turned our sports upside down.
"He is just an incredible individual, passionate. Every kid just loves him and he couldn't wait to get to the OPC (outdoor pursuits centre) to lead the kids through. He will be incredibly missed in more ways than we can say."
Mr Burton said the inquiry was at an early stage but he had no difficulty with the decision to go on the river in the face of severe weather predictions.
"We have been going to OPC for many, many years and I have no reason to doubt the call. Hindsight is a great thing. Obviously there will be a full investigation and debrief into that.
"I don't think the teacher would have consented to taking the students if he had had a doubt in his mind. Clearly it was something that happened very quickly.
"OPC have a fine record and at this stage I certainly wouldn't be judging them on that."
Mr Burton said he had yet to get exact details of what happened but he said the students and teachers in the river group all wore wet suits, lifejackets, warm polypropolene clothing and hard helmets.
"They were very well equipped.
"We understood the party was either entering and doing the gorging or the canyoning.
"One group, probably the party of the deceased, got a little bit further ahead or separated from the others.
"The water suddenly rose and they got swept into the water.
"We think that probably hitting rocks and things like that may well have contributed to a number of them losing their lives," Mr Burton said.
He said they were doing things by the book.
"You are talking very sensible students and a very sensible teacher," he said.
Mr Burton said the rest of the school group from the outdoor pursuits centre were returning by bus today and would be met by families, school staff, church and trauma counsellors.
Students at the school were due at a special assembly to be told of the tragedy and Mr Burton said the school auditorium had been set aside as a counselling and grieving area for students and parents.
"We will spend some time, as long as is needed, with them."
Mr Burton said it was not a day he was looking forward to but there was good support in the school and they would deal with it moment by moment.
He said he had to be strong for students, staff and families but he also had his own emotional moments.
"I willingly put that aside to enter into the grief, to provide the support for those precious families who have lost their children."
He said he was struggling to find the words to describe the enormity of the tragedy.
"Any death in a school would be unacceptable ... but to have six students and one teacher ... and we are talking very fine young students who were lined up to be prefects next year, a teacher who is a stunning individual, a stunning man...
"Words fail."
He said they now needed to stand "shoulder to shoulder and go forward."
He said no matter how strong their Christian faith and core values, it "always rocks you.
"It creates questions in your mind and some of those questions can never be answered. You have to live with mystery.
"But I think on the other hand, our personal faith in God ... we at least believe that he knows. Whatever his perspective is on the matter, we believe he had a purpose in it and we must hold onto that.
"It is not until you get into these sorts of times that you discover the depths of your own beliefs and the character of your school or organisation," he said.
Mr Burton said many students arrived at school today in deep shock but they would be told it was all right to show their grief.
"I will speak to them with carefully chosen words and say it will affect everyone in different ways. You must let your grief show, you must do what you need to do. We are here for you.
"Today we must shepherd the situation. We need to stand with people and guide them through," he said.
He said the pain the school and everyone involved was going through was immense.
"And it will continue for some time to come," he said.
- NZPA
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