This doesn't answer my initial question. Where do rights come from and how are they defined? From your posts and quotes it would seem you believe rights come from society. So, why didn't you just say so in the first place?
Now that we've established that you believe rights come from society how are said rights defined?
Depends on the pool, doesn't it? The right to use a public pool might be extended by a city government. The regulations defining the manner in which such rights may be enjoyed are the subject of federal, state and local law and regulation.
Where would you contend that the right to use a public pool comes from, if not society?