We have a pool and the best investment I ever made was a pool alarm. It goes off if anything more than 5 pounds falls into the pool. It is kind of a pain to take out everytime you want to swim but well worth the peace of mind it gives in the long run. I would highly recommend looking into it. We didn't do this until we experienced a sad puppy accident so needless to say we are big alarm people. Full grown dogs probably aren't such a security problem but better safe than totally sorry. Hugs, Julie