Waters had been feeling a bit unwell at the weekend while watching her sons' league team, Ngaruawahia Panthers, play in the semifinal of the Waikato competition.
However, she carried on and went to work on Monday with her daughter-in-law.
"She had noticed it on Saturday, at the semifinal and felt it with the cold wind and stuff like that and then had a heart attack on Monday while they were preparing the food in the canteen at school. She just felt unwell and couldn't breathe and just went down."
Waters had this year taken over the contract for the school's canteen and was enjoying it, she said.
However, she wasn't just known for her work at the school, she was also a staunch supporter of her three sons' - Cody, Drew, Troy - rugby league club, Ngaruawahia Panthers and had worked in its canteen for many years.
Waters got her first job in a bakery at age 12.
Since then she and her mother had set up and worked in several takeaways in the town - Waingaro Takeaways, Bluebird Takeaways and Riverview Takeaways.
"We've always been in food which is not such a good thing as we always eat it."
As well as being a grandmother of 14 kids, Waters was a mother to five of her own.
She had also taken on her sister, Catherine's, two children, Rain-Skye and Autumn-Breeze, after she died six years ago.
As the whanau had been inundated with visitors and well-wishers, the impact of her death was yet to sink in.
"We're just too busy at the moment, it will hit us later I think when she's not around. Her husband, Wayne, is totally devastated, too," Paul said.
"Because she's so well-known the family's just had hundreds of people around. We had 80 people waiting to come in at one time from the league club [Tuesday night] ... we've got huge tents everywhere outside."
Ngaruawahia High School principal Chris Jarnet, who was on his way to get a pie from the canteen at the time, has closed the wharekai for the week out of respect for Waters.
Her death had also been a huge shock to the staff and students, some of whom were in the wharekai when she collapsed, he said.
"We had to move the kids out. It's all open plan [inside the wharekai] ... they were really worried and people worked on her for quite a long time."
Waters' nieces and nephews also attended the high school and were present at the time, he said.
Waters was a woman entrenched in her community, "she was one of those people who just mucked in."
"They were always respectful, always tidy, it was just very homely. People felt really comfortable around her, it's been a massive shock to us."
Paul said Waters had not only helped care for the grandchildren but also for her 91-year-old paraplegic grandmother.
"I'm going to be a bit lost, she lives just at the back [of my ] fence, she was always over here to see her grandmother."
But it will be the children who are likely to take it the hardest.
"She has 14 grandchildren, and really, her grandchildren are her life. They just about live over at her place, sleep there every weekend. They're going to miss her terribly. It's going to mean a huge upheaval. The grandkids are going to miss her so much. There wasn't a day that she didn't see them all."
Waters will be farewelled at a service at the family home tomorrow morning.
