The person that got the ticket could get an attorney to represent him and ask the judge to dismiss the case on the basis that the ticket is enforceable under Kentucky Law. For anyone interested, the Kentucky case that disusses the issue of public right to navigable waterways is Pierson V. Coffey, and it is published in book 706 of the Southwest Reporter, page 409. You can read and or copy it at any local law library. Again, I am not sure whether the CQ is exempted from this because they trenched out private property to create the bay, but I would argue that they extended a navigable waterway and in doing so made it open to public navigation.