I don't have a pool, but I take the girls to the lake and Maggie loves to swim. Susie isn't so fond of it, but she'll get in the water up to her belly and play. But she won't swim.
The way I got Maggie to swim was this: She LOVES sticks. She hasn't met a stick she didn't want me to throw and chase. So, I started tossing sticks into the shallow part of the water, where she could walk out, water to her belly, and she'd do so, and get the stick and run back into shore.
Then I gradually tossed it further until I was tossing it to where she had to actually swim to get it. She did, no problems. And she turned herself around in the water and swam back.
One thing I note is that she isn't the best swimmer in the world. And when she's tired, her little bottom sinks and she has to struggle and struggle, waving and slapping her front paws in the water to make it back to shore. So I always make sure not to do this when she's tired, so she'll have the strength to swim back.
If you have a pool, maybe tossing a tennis ball or floating ball of some sort that she likes to chase into the water and see if she'll go get it. Or maybe she's like Susie and just isn't interested in swimming at all.
Good luck.