The youngster placed first in the 5km tadpole division race on a single ski.
Gene Hollands was competing in the Bridge to Bridge event and his daughter had decided she wanted to race too.
"She loves it," he said.
The proud father has been water skiing for more than 30 years and helped coach his daughter when she also took a liking to the sport.
"I bought boats before I bought cars," he said.
"We believe it is a good family sport."
The Hollands family are members of the Piarere Water Ski Club near Lake Karapiro and enjoy getting out on the water at Hunters Creek.
"It has always been my little sanctuary," Hollands said.
He said Ellie planned to do more slalom skiing - slalom water skiers use only one ski with feet oriented forward, one in front of the other.
"Her style has come from a slalom background from watching us," he said. "She has really natural balance."
Ellie had reached speeds of up to 35km/h on her single ski and her dad said she loved speed.
"That just comes from her enjoying it. She has never had a fear of it.
"We have put absolutely no pressure on her. We have been in an environment where the kids are in and around boats. It is their natural environment."
He said Ellie enjoyed every aspect of water skiing.
"At home she always gives me a hand to clean her gear and helps to wash the boat."
Bridge to Bridge event organiser Brad Dutton said Ellie's performance in the tadpole event was impressive, even though she was the only competitor.
"The cool thing was she was on a single ski, whereas a lot of kids her age are still learning to grasp two skis," he said.
"To cope with the distance too was impressive."
He said age was no barrier for the sport.
