When the annual North End regatta ended at Lake Waihola last Saturday, North End held on to the trophy with a narrow two-point lead over Otago.
But when chief umpire Royce Wilson checked the results during the week he found two errors.
When the revised figures were added up, it turned out the Otago club had won the regatta with 55 points, from North End 54 and Otago University 42.
The Otago club is in a rebuilding phase and consists of masters rowers and juniors. It does not have any rowers in the elite class.
"We were ecstatic when we heard the news," club captain Michelle Johnson said. "It is the best result the club has had for some years."
The Otago club was pleased to come so close to North End when the preliminary results were announced last Saturday. The amended result sent the club into raptures.
It was not a good regatta for the host club, which also lost the F W Eggers Memorial Trophy for the men's open four to Otago University.
The Otago club won the Butterfield Shield for the 12th time. It first won it 1941, and the last two occasions were in 1999 and 2000, when Sergio Salis coached a talented group of girls from Queen's High School.
The shield was first contested in 1939. It was named to honour the Butterfield family's contribution to Otago rowing, particularly Charley and Monty Butterfield, who were life members of the North End Club.
The family owned Butterfield's department store in the Octagon.
