John Morillo, 47, of Windsor, Ontario, undertook the cross-border challenge from Windsor to Detroit and back Monday night to show "I could do it." He also admitted it was "really stupid."
His actions sparked an international rescue effort after a neighbor, watching the event, lost sight of him after about a half hour, and called police.
He swam from Windsor to Detroit's Renaissance Center, left the water, and dove back in for the return trip, he said, when he noticed the boats and the helicopter, from Canadian and U.S. agencies, sent to find him.
Just before he arrived back in Canada he was picked up by Canadian authorities in a boat. Morillo was arrested for intoxication in a public place, and will likely be cited for swimming in a shipping channel and fined between $5,000 and $35,000, the Windsor Star reported Wednesday.
"The [Windsor] harbor master was extremely mad at me," Morillo later said. He added he has been barred from city waterfront property, and his mother told him, "You're just so stupid" before she hung up on him.
"I apologize for all the people that had to go our looking for me," he commented.