Although she was born with sight, Ms Macdonald gradually lost it, discovering at 8 years old that she had an autoimmune issue.
At 17 she registered with the blind foundation, with her sight becoming so limited she could not see a foot in front of her, or people's faces. After undergoing surgery in 2013 she regained some partial sight, however still struggles to see.
After being invited to join New Zealand's para-adaptive waka ama team in January, Ms Macdonald took to it immediately.
"I could never do netball, I could never see well enough," she said. "So being able to compete in a team sport that you don't need to really be able to see in, that for me was awesome."
"Just being out on the water it's like another world out there, you just get to paddle and not think about anything except paddling faster."
After only five months of "intense" training - at Pandora Pond, out in Hawke Bay, or on machines at her coach's house - she found herself in Australia at the waka ama world championships, competing alongside six teammates - including four others from Hawke's Bay.
It wasn't easy to get there. Without any funding - except sponsorship from local lions, and rotary clubs - the team had to fundraise through sausage sizzles, a givealittle page, and even a 24-hour "paddle-a-thon".
"We just had to get there," she said.
As well as competing in the team event, with encouragement from her coach, Roni Nuku, Ms Macdonald also competed individually - coming away with a gold medal in the 500m race, and a silver in the 250m.
Winning the gold was a "massive surprise", she said, making the challenge of getting to Australia worth it.
It had been hard for the mother-of-three to balance her training with a new job at Napier City Council, as well as teaching self-defence to schoolchildren.
She has worked at the council 20 hours a week since being employed there through the Mainstream Programme - which aims to support people with disabilities into careers -
and will go up to 30 hours next year.
"It was really hard but I had lots of support, work was really supportive and my mum looked after my kids while I was away," she said. "You just make it happen."
As well as enjoying waka ama itself, Ms Macdonald said being a part of the team, and training with other disabled people was inspiring.
"I've always been really positive [about] just trying stuff but they made me even more positive," she said. "You've got people with no legs, you've got people in wheelchairs ... I'm pretty lucky in a way, I just can't see that well.
"I really admire them and their positive outlook."
Ms Macdonald hoped the low profile of para-waka ama in New Zealand could lift as more people become involved in the sport - with disabled people able to compete in open divisions as well.
She hoped this could also be helped by her nomination, showing people they could "give things a go".
"You don't have to be trained in a sport since you were little to become good at it," she said. "Just try things out, and it doesn't matter what the barriers are you've got to find a way around it."
Since the worlds, Ms Macdonald now competes blindfolded in a single waka with her coach paddling behind instructing, normal waka ama, and has even received a bronze medal in a Tauranga marathon.