They say that drowning people don’t shout for help or wave, and may not even splash that much. Maybe most people who drown are just below the surface when they die. You can get caught up in something and dragged into the deep, and perish there, arms reaching up vainly; but you can also slip just low enough that your upturned face doesn’t quite break into clear daylight, and your arms spread wide hold you there, almost, but not quite, breathing air.
I was pulled from a pool once in such a condition. But that was many years ago.
Truly the deep is well named. There is a flood of misery covering the earth, and black horrors in it, and ghastly creatures live there. And what mighty storms rage upon it! Yet one may drown in the merest sunny pool of calm water.