It makes a lot of sense. If they are going to go through the trouble of making the waterways navigable, they better give people a reason to stop.
Quotes about navigable (3 Quotes)
When they say 'navigable,' they are referring to a definition that dates back to the 19th century, not the Clean Water Act. But even using that definition, it has long been accepted that the U.S. can protect upstream waters in order to protect downstream waters.
Congress did not intend the term 'navigable waters' to be given the broadest possible constitutional interpretation.