Drowning is the leading cause of accidental death in children younger than 14 [source: Brody]. While oceans, lakes and rivers present a host of challenges, many drownings happen in a parent's own backyard, often with a parent in attendance. That's because drowning can happen extremely fast -- in the time that you take to turn around, a child could be gone.
If you have a backyard pool, it's important to fence it adequately. That means that it should be enclosed on all sides by a fence that's at least 4 feet (1.2 meters) high. The fence should be free of handholds and footholds, and its latch should be high enough that a small child can't reach it. Many people consider their house to be the fourth wall of this enclosure, but that's inadequate, particularly in summer when screen doors, which toddlers can open, are in use. If your home does open out onto the pool, consider installing alarms on the door, so that adults are alerted when the doors are opened.
Children should take swimming lessons, while adults should take swimming and water safety classes. However, a lesson isn't enough to stop a child from drowning, so children must be supervised constantly while they are in the water. That doesn't mean that an adult can read a magazine or talk on a cell phone while the children splash about -- active supervision is key. If the supervising adult needs to take a phone call or a restroom break, children should exit the pool and leave the pool area until the adult can return. These rules may sound draconian, but again, it only takes a few seconds to drown in just a little bit of water.