Water parks are relatively safe when children are under supervision by parents or responsible adults, but on busy days when they are packed with children it is easy for accidents to happen and for youngsters in difficulty to go unnoticed. It can be hard to tell the difference between someone genuinely screaming for help and someone screaming because they are having fun. Also, slips and falls are likely to happen on wet surfaces.
I love water parks, but one of the things I love about them is you can go about your business without hardly being bothered by park employees. Even if you are engaging in a dangerous activity, there is rarely anyone around to tell you not to. For this same reason, I do not let my kids go.
There are certainly some inherent dangers involved with water parks. You can never completely avoid accidents. People are imperfect and will make mistakes that will sometimes result in injuries. I think water parks generally are quite safe and do a good job of creating a safe environment for their visitors.
No, water parks are relatively safe and have provided hours of entertainment for families and children without injury. The few recent cases of injuries at water park are isolated events. These injuries, when compared to injuries of other activities, fall well below the minimum of what is considered a dangerous activity.