I am brand new to sculling (I just entered my third week of rowing on the Connecticut River) and am learning not only about how to keep my boat stable, but also about the rowing culture. During my two-day Learn-to-Scull class, my coach introduced us to the etiquette that governs river travel. What I have found very interesting, is that these rules almost seem to be universally accepted, at least in the United States.
Lane Direction: The upstream and downstream lanes are the same as a road, so you always row on the starboard side the river. Beginners are encouraged to row closer to the shore, in order to allow faster boats to use the middle of the river as a passing lane.
Launching: With lane direction in mind, when launching off the dock, always push off with the bow facing upstream. This is to avoid having to cross a lane and to prevent possible collisions. Also, if other rowers are waiting to launch, strap in and make stretcher adjustments in the water. Do not make the other rowers hold their shells on their shoulders for any longer than necessary.
Right-of-Way & Yielding: In terms of sweep and sculling shells, boats must yield to the larger and/or faster boats. So a single scull must yield to a double, a double to a quad, etc. (Technically, sailboats have the right-of-way over all other boats, and rowboats and canoes have the right-of-way over motorboats. But as a rower, it makes sense to yield to a motorboat because it is faster.) And whatever the size, a scull or sweep needs to yield to a faster scull or sweep. When overtaking a slower boat, passing should be done in the middle of the river. If being overtaken by another shell, it is important to yield towards the shore and to announce your presence as soon as possible to help avoid collision.
Landing: When landing, one should approach the dock from downstream. Land on the downstream most section of dock (this allows for others to launch) then walk the boat upstream to make room for other boats that may be landing.