Two children swimming. One uses an inner tube; the other holds on to the tube's edge.

You may think you know what drowning looks like. But if you’re like many of us, someone could drown just feet away from you without you even realizing it. 

“We see it popularized in media and movies as this big, dramatic event where people can wave and are screaming,” says William Ramos, Ph.D., a professor in the School of Public Health and director of the Aquatic Institute at Indiana University Bloomington.

Actually, drowning is quiet, with subtle signs that are easy to miss. That can be particularly problematic in crowded, unfamiliar, or challenging conditions—like the quickly changing depths of the ocean’s sandbars or murky lake water—when swimmers, especially young ones, can get into trouble quickly.

In fact, a report issued last month by the nonprofit group Safe Kids Worldwide (PDF) revealed that the largest percentage of fatal drownings in kids 19 and younger occur in open water, such as lakes, oceans, and rivers.

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You can safeguard yourself and your family by giving kids swimming and water safety lessons and assigning adults to maintain a watchful eye—even when there’s a lifeguard on duty. (See more on swimming safety here.)

But experts say it’s also important to be able to identify a swimmer who is in distress. 

Here’s what you need to know and what to do to help.

What Drowning Looks Like

When a person first begins to have trouble staying afloat in water—sometimes referred to as distressed swimming—he or she might briefly be able to wave or call out.

Not all distressed swimmers will do this, however, and they may soon begin to drown silently if they don’t receive help, the American Red Cross says. 

“When you can’t breathe, you don’t have the breath to shout for help,” says Linda Quan, M.D., a pediatric emergency physician and professor at the University of Washington School of Medicine.

A drowning person may have as little as a few seconds before he slips fully under the water, so it’s important to understand the not-so-obvious signs.

An “actively drowning” adult or older child will usually be vertical in the water with his arms out to his sides or in front of him—trying to push down to lift himself above the waterline. His head will probably be just at the waterline and tilted back slightly. (See two images [PDF] of this from the Red Cross’ Lifeguarding Manual.)

Infants and toddlers, whose heads are heavy in relation to their bodies, won’t have the strength to push themselves up with their arms. So their mouths and noses will probably be under the water with their arms and legs barely moving. They may be completely submerged or face-down on the surface of the water.

(Older children and adults may also display this behavior—known as passive drowning—especially if they’ve also experienced a medical problem, such as a heart attack, or have consumed alcohol.)

What Should You Do to Help?

If you see someone displaying the signs of drowning listed above, call out to them, Ramos says. “If the person can’t respond, that’s your first indicator that they are truly in need of help,” he says.

Ask someone nearby to call 911 while you try to help the drowning person. If there’s no one else around, help the person first, then call 911 yourself. 

Your first instinct may be to jump into the water and grab the drowning person. But resist the urge. 

“The hardest part, if it’s a loved one, is to keep yourself from going in and doing something that’s going to harm you,” Quan says. Here’s why: Drowning people may instinctively grab on to you and—inadvertently—push you under the water.

Instead, first try to reach them from land. If you’re in a pool, lie down on the edge of the pool deck and reach your arm out to the person. Or stand on the pool’s ladder, holding the bar with one hand, and reach out to the person from there.

For any body of water, you can also use an object to extend your reach—a pool noodle, an oar or a paddle, a rake or another garden tool, or even a loose tree branch. The drowning person can grab on to one end, allowing you to pull them to safety.

If you are unable to reach them from land, toss the person a flotation device. An inner tube, a life jacket, even a sealed and empty cooler or water jug will do if no lifeguard ring is available. Encourage him to hold on to the object and try to paddle to safety.

If a drowning person is simply too far out for you to toss her a floating object, Ramos recommends that you (or the most competent swimmer in your group) grab an item that can provide flotation and swim toward the person. But don’t make direct contact.

Once you get close enough, extend the item toward the drowning person, keeping a safe distance from him, Ramos says. Hold on to the other end of the person’s flotation device, and, without touching him, swim him to solid ground.

If the person is unconscious, try to get a flotation device around her so that she can stay afloat, Ramos says. But if the person has already gone under and is unreachable from the surface, the Red Cross recommends waiting for professional help.

Once you’re both back on shore, if you haven’t yet called 911, do so right away. Even if the person you rescued is awake and alert, he should be evaluated by an emergency medical technician.

And if the person you’ve rescued is unconscious and no one in your group has CPR training, the 911 dispatcher can coach you over the phone.

If someone does have CPR training and determines that the rescued person needs it, she should start right away. (Experts say all adults should know how to do CPR—for more on this, see our report.)

Finally, create an emergency plan for the future. Before you visit swimming areas with friends or family, determine how you might contact emergency services in the case of spotty cell service. When you pack your beach bags, include at least two flotation devices that could be used in the event of an emergency.