My grandparents had a trailer on a lake with a pontoon. Neither of them could swim. They insisted I take swimming lessons at an early age before I was allowed to come to the trailer with them. Grandma even insisted taking me to my lessons so she could watch and be sure I could actually swim. Guess the certificate wasn't going to cut it for her. lol

Also every year when I went to summer camp you had to take the daily swimming lessons or you weren't allowed in the water during free swim in the evening or to go on canoe trips. It didn't matter how many years you'd been going or regardless of any other swimming certificates you had either.

The only thing that has ever baffled any of my swimming instructors is that their ways of teaching me to swim wear me out fast, I HATE treading water their way, can barely make the 2 minute minimum to pass. However if I'm allowed to swim my way I can be in water over my head for at least 1/2 hour without touching bottom before I'm tired. I can also swim for a short time using only my arms, or only my legs when I want to.

I hate putting my face in the water if I don't have to, but I can swim their way to satisfaction if required.

Doesn't matter to me if the water is 10 feet deep or 100 feet deep, it's how far from the shore (or a boat) I am that is likely to make me a bit nervous if at all.