Vivienne Moxham-Hall would love to compete in winter swimming championships, but her hopes have been frozen due to a rule that excludes women.
Women are not allowed to take part in the competition because six of the eight clubs in the South Coast Winter Swimming Association have voted against women becoming members.
President Bill Steele said most of the association's eight clubs "just weren't interested" in expanding to include women.
Mr Steele is also president of the Austinmer Otters, one of the six clubs that voted a couple of years ago against allowing membership for women, meaning women who are members in the other two clubs can't swim in the association championships.
"We just seem to think it's our little right to have our own club," he said.
As the clubs prepare for the season, Ms Moxham-Hall and her other women members at the Stanwell Park Sea Eels will have to be content with sitting on the sidelines cheering their male teammates on.
"I think it is absolutely crazy that even though I am a member of a winter swimming club, I can't compete because of my gender and it makes me very, very angry - and it's frustrating," the 23-year-old said.
Barry McGuinness, a captain at the Sea Eels, said: "It comes up fairly regularly and it just gets shot down in flames, and they don't give a reason."
A spokesman for the Wollongong Whales wrote: "I believe that it is in the South Coast Association minutes and constitution that the championships are for male members only. Each club has their individual constitution that may allow for ladies and children to be members of their own clubs."
The president of the NSW Anti-Discrimination Board, Stepan Kerkyasharian, said because it was a voluntary association it would not be bound by anti-discrimination laws.
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