Guess I'll add the peeing and pee tags then. Hmmm, for some reason I always recall that scene incorrectly as spitting.
Updated
I've come to buy black tea.Method 2.
Gliding on the water surface
This method of movement disregards the design elements on their upper bodies. Some girls wear shoes specifically designed for this.
I think this is the most reasonable one.Kancolle
Imagining how fleet girls swim
Method 1.
Half submerged
Some girls, like Kongou for example, have a boat attached to them so they're meant to be half submerged. But then some girls have equipment on their lower bodies so this wouldn't work.Method 3.
Appear like stands spirits or fairies
My personal favorite.Method 4.
Don't actually fight in battles
If they didn't need to fight then they don't need to enter water either.