I have an above ground human pool for my kids and 4 kiddie pools for my 8 geese and 7 ducks. My above ground pool is tall enough (4 feet) that they can't get in, and any bird that can lift more than 2 feet off the ground has its wings clipped immediately. My back fence is only 3 feet high, so that's why the 2 foot rule. All my chickens wings are clipped regularly. My chickens kept going over the fence to tear up my mother's garden (she owns the property behind me), so we started clipping to keep them out of there, lol. So far the ducks and geese have only managed to get a few inches off the ground, but we are watching them closely. When our human pool is not in use, we remove the ladder to prevent the chickens from climbing it and falling in. If your pool is in the ground, you will have to fence it off to keep the ducks out. The chlorine is not good for them, and swimming in duck poop isn't good for humans either (at high concentrations, which would likely happen if you allowed the ducks in the pool). I have not found a good way to keep a pool clean enough for both ducks and humans, if you discover a way, please share. Until then I will have human pools and waterfowl pools to keep everyone happy.