Riley avoids swimming in the ocean, and hasn't had a chance with a pool yet. My prior dog, Frankie, wouldn't stay out of the pool. She would run around, get hot, and then swim to cool off. If she heard a splash in "her" pool, she would go crazy and howl until someone let her in the pool area. She was a nut about swimming .

However, Fenway is very afraid of in-ground pools. When we're in the pool, he runs upstairs, curls in a ball and takes a nap. I carried him in the pool once and put him in. He freaked, got out and we didn't see him for about 2 hours. I don't know what it is about in-ground pools.
I wonder if it has do do with splashing? Another one of my dogs would swim in a pool, or lake if there was no loud noises. The second there was splashing and people swimming, she was out of there.