Peter Caughey, of Christchurch, won the Superboats class, Ollie Silverton, of Hamilton, won the Group A class and equal first in Group B were Clayton Tisdall, of Tapanui, and Patrick Haden, of Otorohanga.
Organisers estimated nearly 4000 spectators sat on the banks of the Oxbow Aquatrack, next to Wanaka Airport, on Saturday to watch the driver and navigator teams sprint around the knee-deep purpose-built water track.
Thirty-one boats competed, many of those from the North Island.
The South Island's only jetsprint club, the Southern Jetsprint Club, hosted the event and founding members (driver) Clayton Tisdall and his (navigator) wife Mandy designed the six-island Aquatrack course in an area the size of a rugby field.
Mr Tisdall said the trickiest part of the event would be going around the island in the middle as the boats would create a wash which could ''unsettle the boat''.
''If the jet unit breaks from the water you lose suction and you've got no power, no steering, no nothing and it's all over.''
Mr Tisdall started jet sprint racing when he could no longer ride a motorbike because of a wrist injury.
The joint winner of the Group B jetsprints, he said the sport was ''addictive'' and gave the ''biggest adrenaline rush.''
''You can go from 0 to 120kmh in about two and a-half seconds and when I get out of the boat my hands are shaking,'' he said.
There are three classes of boats. A and B had strict jet-boat specifications but Superboats could run any engine.
