Originally Posted by Ribochet
The standard International Regulations for Preventing Collisions at Sea would possibly apply to that stretch of water as the Colregs not only apply to all vessels upon the high seas but also to all waters connected therewith navigable by seagoing vessels
Rule 1 part b allows special rules authorized by a proper authority, such as the US where they have separate rules for inland rules, clearly defined on the chart.
However in the absence of any other rules, I would suggest rule 5 stands.
There are IMO rules regarding minimum area of visibility (SOLAS convention) but again, it would depend on the local rules, and the classification society, and registry if these apply in is case.
However the "Ordinary practice of seamen" under rule 2 would suggest a lookout would be prudent.