Are swimming pools potentially dangerous for previously indoor-only cats?

If your cats have been strictly indoor cats, then they may not be that interested in going outside. My last cat lived indoors for her first 3 years, she had never been outside. Then I moved to a place that I could let her outside in the back yard. She would only go out when I was out there, otherwise she stayed inside. If you only let them out when someone is around, they'll be fine. They may not go near the pool because it will smell funny to them.