The sport she took up seriously as an eight-year-old had already taken her to Fiji, Samoa, Singapore and Hawaii, where she recently swam for New Zealand at the Junior Pan Pacific Championships.
"I always enjoyed it when I was younger, and I remember how I was just doing lessons when my coach asked me if I wanted to join a club and compete," she said.
"But I wouldn't have thought it would have taken me to Harvard."
With a long-held ambition to study at a US university, the former Diocesan School for Girls pupil emailed a list of institutes she was interested in - and was shocked to receive a reply from Harvard.
While the university was attracted by her promise in the pool, Paterson said it was her performance in the classroom that ultimately secured her a spot.
"I didn't know if I was going to get in because it wasn't based on my swimming results, but my academic performance."
Hailing from New Zealand - a country with almost exactly the equivalent population of the greater Boston area, where Harvard is based - also proved a good thing.
"Saying you're a Kiwi is kind of an advantage, because everyone over there just loves them."
She's unsure what career path she's going to follow, but hopes to study engineering or architecture in her second year.
"I'm keeping my options and I want to see what they've got to offer, but I'd love to be an architect."
And then there's her other dream: sporting the silver fern at the Tokyo Olympic Games in 2020, or at the Commonwealth Games.
"It's funny, without swimming, I don't think I'd get as much done: even though I don't have much spare time because I train a lot, it keeps me way more productive and motivated."
