Water, here in the land of “Ten Thousand Lakes,” is something we often take it for granted. It’s a part of our everyday life. It hydrates us and provides us with year-round outdoor fun. But water can also be deadly, presenting very serious health risks. These safety concerns are at the forefront of our minds during swimming and boating months, when everyone is looking to cool down in the warmth of the summer sun. But cold water can prove just as dangerous, as body heat can be lost 25 times faster in cold water than in cold air.

The dangers of frigid water were highlighted just last January, when a trio of University of Minnesota students had the misfortune of finding out firsthand how cold water can end a life. What started as an attempt by one student to retrieve his dropped cell phone soon became tragedy when his friends, attempting to save him, entered the icy river as well. In the end, two of the three lost their lives that night in the Chicago River.

With extremely cold winter temperatures, it’s more important than ever to spread the word about the dangers of cold water, especially in light of the recent popularity of the “Cold Water Challenge,” a charitable dare that, for some, is proving fatal.


At the heart of the cold water challenge there is a good intention – to raise money for charity. Basically, participants are elected by family or friends, through social media sites like Facebook, to take part in the challenge. If you’re nominated, then within 24 hours you either have to donate money to charity (NOTE: this isn’t always part of the challenge) dump a bucket of ice water on your head or jump into a cold body of water, posting a video of the feat online. Once the task is completed, it’s then your turn to nominate the next person.


Jumping into cold water is a shock to the system. Upon hitting the water, the jumper involuntarily gasps for air, often taking water into their lungs. According to Kara Owens of the DNR, it only takes a half a cup of water in your system to drown.

The shock to your body can also cause disorientation and makes swimming difficult, as it requires more energy to swim in colder temperatures than it does in warmer ones. Finally, there’s also the risk of cardiac arrest and hypothermia. All of this adds up to a deadly combination that can quickly cause a fun escapade to escalate into a life-threatening situation.

Minnesotan Davis Colley, age 16, was nominated for the challenge last May and as a result, died in Eagle Lake. The biggest mistake he made was going to the lake alone after texting his girlfriend earlier that day to let her know that he was planning to take the challenge. At that time, the water temperature was around 40° Fahrenheit. The Department of Natural Resources (DNR), who has actively spoken out against the cold water challenge, considers water below 70 degrees to be cold.

What is a safe water temperature for swimming?

Safe swimming temperatures depend on several factors: age, the type of swimming you plan to do (laps, racing, recreational), and health. Here are some general guidelines:

40° F or lower means the water feels painful to swim in.

70° F feels very cold to the average person. The National Center for Cold Water Safety urges swimmers to “treat any water temperature below 70F with caution.”

77-82° F is the temperature range used for Olympic competition.

85° F feels pleasantly cool to most people.

82-86° F is recommended for children and older adults.

84-86° F for babies.

78-84° F for pregnant women.

Anyone with a health condition should consult their doctor before swimming.


Any body of water, at any temperature can be dangerous, so always have a buddy with you when playing in and around water. It’s always better to have someone with you, who can call for help, in case something goes wrong. Remember, in the case of cold water, never enter the water yourself to save a friend – as we saw with those University of Minnesota students, you’ll risk losing both your lives. Try instead to call for help, or throw in a rope or safety flotation device to pull someone who is struggling out of the water.

If you’re a parent, talk to your kids about the dangers of the Cold Water Challenge. Caution them not to take part in it (either by doing it or nominating someone else for it). Let them know that it’s okay to speak out against the challenge if someone in their circle of friends is considering it. The more the word gets out that this fad is dangerous, the better. You just might save a life.

For more information on preventing cold water hypothermia, visit SeaGrant Minnesota’s hypothermia page. For more on how cold water affects the body, the National Center for Cold Water Safety has some great information.