The 5E rules for aquatic encounters were smeared over a number of locations and generally left me with a lack of useful understanding. The result was I avoided encounters in the water so I could avoid the puddle of rules that defined aquatic encounters.
The 5R rules have made pretty big changes. I'll dive into how it is defined to work in the newest iteration of the rules in this post. As usual, I'll copy teh relevant rules snippets into this post, after I walk through what I think the rules mean to me and my games.