This is a really important element of the new Canadian navigable waters legislation. I'm happy to explain.
There are two components to the new definition. One, as you've mentioned, is the use for travel or transportation, including for the exercise of indigenous rights, but also for recreational as well as commercial purposes.
The second element is that there be public access, so it protects the public right to navigation where there is public access to a waterway. That would mean there is public access, there's more than one shore owner or riparian owner, or the crown is the sole owner of the shore.