Event sponsor Ohio River Way Inc. said Sunday morning's swim, which was managed by Tuscon Racing Inc., was originally scheduled for July 21, but was delayed due to high E. coli levels in the water and instead took place amid 40-degree air temperatures in Cincinnati and a 77-degree water temperature Sunday, The Cincinnati Enquirer reported Monday.
Marilyn Braun, 79, of Wyoming, Ohio, said she finished the swim in 28 minutes and 42 seconds.
"When you get so old, you got to do something," said Braun, who said she swims five days a week at her local YMCA, but Sunday's event was her first dip in the Ohio River.
Organizers said 68 swimmers were registered to participate Sunday.
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