Despite the wind forcing more than half of the regatta to be canned, Otago crews made the most of limited time on the water to beat out Canterbury and Southland.
Otago finished with 37 points, Canterbury 28 and Southland 18.
Otago's men's and women's coxless quad and coxed eight crews recorded wins, as did the men's under-20 coxless four.
Corey Lewis, Riley Bruce, Bradley Leydon and Charlie Wallis were emphatic winners in the coxless quad, crossing the line almost 10sec ahead of Canterbury in 6min 48.41sec.
The women's crew - Sydney Cook, Macaela Turfus, Lucy Geddes and Riley Homan - were made to work much harder for their win in the quad.
They were pushed all the way to the line by Canterbury's sole crew in the race, but managed to hold on to win by 1.2sec in 7min 20.59sec.
Sean Ducray, Philip Wilson, Josh Hayes and Ollie Tyro were far too good for the opposition in the coxless four, finishing almost 15sec ahead of Canterbury in 7min 0.72sec.
They were joined by Bryce Abernethy, Andrew Potter, Hugo Elworthy, Tom Clyma and coxswain Sachin Arulambalam in the eight, where they again beat the red and blacks.
Otago clocked a solid 6min 23.60sec on its way to first, while Canterbury (6min 35.81sec) and Southland (6min 37.92) scrapped it out for second and third.
The women's eight of Hazel Cunliffe, Anna Watson-Taylor, Ella Greenslade, Claudia Maker, Juliette Alm-Lequeux, Kelsi Parker, Natasha Bonham-Carter, Maysie Scott and coxswain Charlotte Kenny clocked 7min 15.89sec to cross the line first ahead of Southland, which was second in 7min 19.81sec.
A bunch of Otago crews finished on the podium in some of the other completed races, including Bruce and Wallis in the men's under-20 double scull.
They finished second behind Southland's Tim Yaxley and Thomas Elder in 8min 44.92sec.
Geddes and Homan finished second in the women's under-20 double scull, while Clyma and Elworthy were second in the men's open coxless pair and Cunliffe and Bonham-Carter were second in the women's open coxless pair.
Otago rowers also performed well in the R2K singles regatta, which was also held on Lake Ruataniwha at the weekend.
Watson-Taylor (Otago University Rowing Club) recorded a good win in the women's open race, while Bruce (Wanaka) and Mark Taylor (Oamaru) won the under-18 and under-17 races respectively.
