What You Need To Know About Cold Water Drowning


Northern Nevada is home to some of the most gorgeous and pristine lakes in the country — but also some of the most unforgiving. Lake Tahoe water temperatures average 50 degrees in the summer, making the danger of hypothermia real and always present. Here are the signs, symptoms and ways to prevent cold water drowning.

When we think of air temperature at 50 degrees Fahrenheit, it’s not all that cold. But when it comes to water that’s 50 degrees, there is no comparison. Immersion in cold water is life threatening and can happen within a minute of entering the water. Taking the right precautions before entering the water could save your life. 

The Four Phases of Cold Water Drowning

  • Cold Shock Response: This response affects breathing and happens within the first minute. An automatic gasp reflex occurs in response to rapid skin cooling. If the head goes below water, water may be breathed into the lungs, resulting in drowning. A life jacket will help keep your head above water during this critical phase. Additionally, hyperventilation, like the gasp reflex, is a response to the cold and will subside. Panic will make this worse, so the key is to control breathing.
  • Cold Incapacitation: This response occurs within the first five to 15 minutes in cold water. In order to preserve core heat, vasoconstriction takes place decreasing blood flow to the extremities to protect the vital organs. The result is a loss of movement to hands, feet, arms and legs. Unless a life jacket is being worn, the ability to stay afloat is next to impossible.
  •  Hypothermia: It can take 30 minutes or more for most adults to become hypothermic. This is important to note as there’s time to take action and survive — keeping panic at bay is critical as you have more survival time than you think. Symptoms include: 
    • Shivering
    • Slow and shallow breathing
    • Confusion
    • Drowsiness or exhaustion
    • Slurred speech
    • Loss of coordination
    • Weak pulse
  • Circum-rescue Collapse: This phenomenon can happen just before rescue and is not well understood, with symptoms ranging anywhere from fainting to death. Some experts believe an abrupt drop in blood pressure may cause this final stage of cold water drowning post-rescue.

Additional Safety Tips and Helpful Resources

  • Always wear a life jacket, wetsuit or drysuit. Your life jacket is the most important piece of water safety gear. 
  • Try not to panic as the first phases will subside. Controlled breathing is key in calming down the body and mind. Research suggests that the body can withstand the cold longer than we think.
  • The Heat Escape Lessening Posture (HELP) is a position that can help conserve energy if you’re wearing a personal flotation device. By hugging your knees to your chest, will help maintain body heat for some time.


  1. The word cold is subjective. How cold is cold? You could give an objective reference, for instance water at zero degrees centigrade or icy water.