Yes. Know your rights! In 2014, the Portland Boathouse, a private organization representing the interests of boaters, hired private security to tell swimmers they weren't allowed to swim from the Dock. When WW asked this security guard if it was against the law, he replied: "I'm not sure, but it's a rule." We asked the Portland Police Bureau, which said it was legal to swim from the Dock, and police would not hassle anyone doing so. So you are allowed to swim from the Dock. Anyone who tells you you cannot swim from the Dock is wrong.