We had an outdoor cat live to 16 who drank from our pool all summer long. I'm not saying it's fine, but everything seems to drink from my pool. Raccoons are the worst, they wash their muddy paws first. We had Muskrats move in once. They seemed fine, nothing we did convinced them to leave until our cat (the one mentioned above) got one. He was a great cat, not a nice cat, actually kind of dangerous, but he single handedly kept things in balance. In the warmer months he would eat 10-12 critters a day. Frogs were his very favorite thing. And how many cats can kill a Muskrat? Sorry to ramble, I miss the crazy ultra-violent guy to this day.