Don't die in a cold Minnesota lake
Water temperatures now can render you unable to function within minutes — if you even live that long.
DULUTH — On April 29, 2022, two men were headed out fishing on Big Marine Lake in Washington County, Minnesota. Their boat left the launch at high speed and suddenly turned sharply left, throwing both men into the water.
There were two life jackets in the boat, but neither man wore one. Another boater saw what happened and immediately tried to rescue the men, but both had already gone under water, unable to swim or even stay afloat for a minute or two. Their bodies were recovered later.
They were the state’s first of 18 boating fatalities of 2022, the Minnesota Department of Natural Resources reported, but typified a common problem: If you fall in when the water is as cold as it is right now, especially without a life jacket, you may die.
The majority of cold-water drownings happen before hypothermia even kicks in because they aren’t wearing life jackets and they can’t survive that initial cold-shock gasp.
The water temperature of many Northland lakes for the mid-May Minnesota fishing opener is usually about 40-50 degrees. That’s also often the temperature of Lake Superior water on many midsummer days.
“And it’s not just boaters and fishermen who are at risk here. Paddle sports like kayakers and canoes and stand-up paddle boards now account for 30% of boating fatalities,” said Lisa Dugan, recreation outreach safety coordinator for the Minnesota Department of Natural Resources. “These are people who tend to get on the water early in the season. And we find that a lot of them don’t know they need to have a life jacket.”
Shock, then panic
The first chances at death you'll face if you fall in are cold shock and then panic. The initial shock of falling into cold water can place severe strain on the body, producing instant cardiac arrest or even stroke.
Survivors of cold-water accidents have reported that their breath was driven from them on first impact with the water. If you are under water or face down when that involuntary gasp occurs, it is likely will fill your lungs with water, not air. As little as a half-cup of water in your lungs is enough to kill you.
And it’s not just ice water that feels cold. The National Weather Service says that shock/gasp reflex can occur in some people in water as warm as 77 degrees.
Other cold-water survivors report panicking uncontrollably, thrashing helplessly for 30 seconds or more before getting their bearings and calming down, at which point they are already losing dexterity due to rapid body heat loss. Some people never regain composure and go under.
“The majority of cold-water drownings happen before hypothermia even kicks in because they aren’t wearing life jackets and they can’t survive that initial cold-shock gasp,” Dugan noted.
Hypothermia moves fast
Even if that involuntary gasp of water doesn’t kill you, or a heart attack or stroke or drowning from panic, if you can’t get out of the water fairly soon you are still doomed by hypothermia.
Immersion in cold water can quickly numb the extremities to the point of uselessness. According to the National Center for Cold Water Safety, cold-numbed hands within minutes often cannot fasten the straps of a life jacket, grasp a thrown rescue line or hold onto an overturned boat. Severe pain quickly clouds rational thought. Eventually, full-on hypothermia sets in as your core body temperature drops, and, without rescue from the water and then proper first aid treatment, unconsciousness and death occur.
Think of Leonardo DiCaprio’s character in the movie "Titanic": young, strong, hypothermic, dead.
John Downing, director of the University of Minnesota Sea Grant program based at the University of Minnesota Duluth, started delving into hypothermia in recent years in part because he spends a lot of time at his family’s lake cabin in Itasca County. But the more he looked, the less satisfied he was that the public was getting the information needed to avoid tragic deaths on Minnesota lakes.
Even folks who make it to shore, they’re still in a pickle if they can’t get warmed up.
“I’m interested in this personally because I’m a Minnesotan who spends a lot of time outdoors and around water and ice,” Downing said. “But, as a lake scientist, when I started looking for resources, there wasn’t much out there, at least not in one place. … So I started pulling it together during the pandemic.”
Over the past few years, Downing has compiled a wealth of information on hypothermia from dozens of sources at a new Sea Grant website page z.umn.edu/shiver . He’s hoping people use it.
“Sea Grant’s mission is water and people using water, so it really is part of our responsibility to talk about this, to get this information out to the public,” he noted. “Sea Grant is responsible for educating people on the coasts of this country, and we’re the coldest coast of all.”
Rick Slatten, who heads the St. Louis County Rescue Squad, said hypothermia is a big issue in many wilderness and boating search and rescue missions the squad conducts, including extracting people out of the Boundary Waters Canoe Area Wilderness when they aren’t prepared to be there in cold weather, cold-water times of year.
“We deal a lot with hypothermia across the full range of our mission and train extensively on it. Yes, it’s a huge contributing factor to drowning,” Slatten said, noting that getting rapid help rewarming is critical for hypothermia victims who are rescued from their water mishap to survive. “But, even folks who make it to shore, they’re still in a pickle if they can’t get warmed up.”
Slatten said hypothermia is also an issue if injuries are involved, either in vehicle crashes on land or snow or mishaps on the water.
“Hypothermia also inhibits proper clotting of blood in trauma cases. Contrary to urban legend, your blood doesn’t get thicker when you’re cold,” Slatten noted. “In short, if you’re cold. You won’t stop bleeding.”
A body can’t take much cooling off
Our normal body temperature is 98.6 degrees. Shivering and the sensation of cold can begin when the body temperature lowers to 96.5 degrees. Brain function begins declining at 91 degrees and amnesia can set in soon after. Heart rate and breathing slows at a body temperature of 84. Human hearts often stop beating below 79 degrees. So you can see why someone immersed in 45-degree water will perish quickly.
Drownings kill about 4,000 people in the U.S. each year and researchers are increasingly finding that many of these are caused when even good swimmers end up in cold water, according to the Centers for Disease Control and Prevention. They may drown, but it's because cold water renders them incapable of actions to survive.
You might guess that warm-water states would have the highest rate of drownings because people are in the water all year. It’s actually Alaska that has the most drownings per capita — 20 drownings per 100,000 population per year, almost 10 times higher than the overall U.S. rate of 2.11 per 100,000 per year, according to the CDC.
The majority of hypothermia deaths occur in people over the age of 55 in rural environments, the CDC notes, and about two-thirds of the deaths occur in males.
The science behind cold water’s coldness
While 45-degree air feels a little cold when you walk outside, 45-degree water feels so cold that it seems to burn your skin when you are immersed in it. Why is that? The National Center for Cold Water Safety says it's because water has much greater density than air, so it conducts heat away from your body much faster — up to 24 times faster than air.
Cold, shiver, stumble, bumble, sleep, die
The reason accidental immersion causes lost body function and death is because the body's core temperature drops. The human body works well only when it can maintain a fairly narrow range of internal temperature. According to Minnesota Sea Grant, as the body’s temperature drops below 98.6, these are the stages of hypothermia:
- The sensation of cold.
- The onset of shivering, then uncontrollable shivering.
- The loss of ability to do normal physical activities like zip zippers or walking without stumbling.
- Impairment of mental ability as the brain cools — slurred speech, disorientation, sleepiness.
- Lost consciousness, sleep-like.
- Breathing and heartbeat decrease, then death.
The false promise of brandy
Alcohol use opens blood vessels near the skin and on extremities, which increases heat loss from the body. Worse, because alcohol can produce a feeling of warmth, it tends to decrease a person’s perception of actual cold, delays the onset of shivering and reduces its duration, and can impede the body’s ability to regulate its temperature, according to the National Library of Medicine.
Minnesota cold-water boating deaths
Even though most boating is done during warm conditions, over 30% of boating fatalities in Minnesota happen in cold water with a victim not wearing a life jacket, according to the Department of Natural Resources. Falls overboard and capsizing are the most common causes of boating fatalities in the state. Men ages 20-60 are the most likely to drown while boating, and are the least likely to be wearing a life jacket. Last year, there were 18 boating deaths in Minnesota and 53 non-boating drownings.
Plan before you go
Let others know where you are going and when you plan to be back and ask them to call for help if you don’t return on time.
Have a plan to reenter your boat. Very large or elderly people may find it hard to re-board a boat even in warm water conditions let alone very cold water. Consider a boarding ladder or other plan for reentry.
Tips to stay alive if you fall into the water
- Wearing your life jacket could be the single most important factor in surviving cold water. But it has to be on before you fall in. Insulated float jackets and survival suits are even better, if they are worn.
- Stay with the boat. Most capsized boats will still float, and a boat in the water is easier for rescuers to locate than a person alone.
- If you have to remain in the water, do not attempt to swim unless it is to a nearby boat or floating object.
- Keep boots and clothes on to retain warmth. Almost all clothing will float for an extended period of time. The exception is waders and hip boots.
- Curl up into a floating ball: Reduce the effects of cold-water immersion by assuming the heat escape lessening position: Cross ankles, cross arms over chest, hands should be kept high on the shoulders or neck, draw knees to chest, lean back and try to relax.
- If more than one person is in the water and wearing flotation, get into a huddle by hugging close together. Arms should be placed around the backs of the others and kept underwater, while smaller individuals or children can be placed in the middle. The huddle helps conserve body heat and it is also easier for rescuers to locate than one lone victim. The close proximity of victims can serve also as a significant morale booster.
1-10-1: Fight for survival
- You have about one minute to get your breath and thoughts under control to avoid immediate drowning.
- You have about 10 minutes of meaningful movement ability. Find the boat, find other victims, self-rescue if possible.
- If you use proper techniques to conserve body heat you may be able to stay alive for up to one hour with flotation, signaling for help over that time. That time will be shorter if the water is colder than 50 degrees.
Source: Minnesota DNR
- Wear a life jacket. Minnesota law requires a wearable U.S. Coast Guard Approved life jacket for each person on board all watercraft.
- Prevent capsizing. Reduce speed in rough water, don't overload a boat, secure loads from shifting and adjust for changing conditions.
- Prevent falls overboard. Remain seated while underway, avoid a sudden shift in weight.
- Brief passengers. Everyone should know where all safety equipment is, and how to use it, and how to start, stop and steer a boat.
- Keep an eye on the sky and know the weather forecast. No boater should ever set out in a storm.
- Carry a compass and chart. Carry a cellphone or two-way VHF marine radio. The U.S. Coast Guard monitors Channel 16. Take a boater safety course.
Source: Minnesota DNR
After water rescue, warmth critical to survival
A person’s core body temperature can continue to decline even after they are removed from cold water. This is called the after-drop effect and can cause more serious decline, so getting the person warmed is critical.
Even responsive people removed from cold water or excessive cold should not be expected to help themselves.
Hospitals and clinics have methods and equipment that can work more quickly and efficiently to help people recover from hypothermia. If a cold, shivering or non-shivering person is showing altered mental abilities, sleepiness or unconsciousness, or slow or irregular life signs, it is important to seek medical assistance as soon as possible.
According to the Minnesota Sea Grant hypothermia website, increased insulation of the person is important. Use sleeping bags, blankets, bubble wrap, insulated sleeping pads, extra clothing or any other available insulation. If the person is wet and outdoors, wrapping them in a vapor barrier such as a plastic blanket or a foil insulation blanket before wrapping them in insulating material will help to keep the loft and dead-air space in insulating materials working well.
If a hypothermic person can be brought indoors or to a warm and wind-free environment, their wet clothing should be removed or cut away before they are wrapped in dry insulating materials. Ensuring there is insulation both beneath the person and on top of them is important to reduce heat loss.
Warming the person's body core with an external heat source is best, such as chemical hot packs, hot water bottles, electric heating pads or another safe heat source. Heat sources should not be placed on the skin but separated from it by cloth or another insulator to avoid burning the skin.
Do not use warm showers or baths to rewarm a hypothermic person as these could send blood to skin, legs, arms, hands and feet and away from the heart and brain which could cause a dangerous drop in blood pressure.
Assembling a hypothermia survival kit
If you are frequently outdoors in the winter, especially around water and ice, Sea Grant’s John Downing suggests assembling and bringing with you a cold-safety readiness kit. With the exception of a sled, the kit components can be packed into a small watertight container or sealed bag. Some suggested items to include:
- A 20-30 foot length of strong, floating rope with a body-sized loop pre-tied in one end and knots in the other for gripping.
- Waterproof matches and fire-starters for building a warming fire if evacuation to a medical facility is slow or impossible.
- A three-season mummy-style sleeping bag.
- A foil-type thermal blanket.
- Small tarp for shelter from wind and precipitation.
- Gel chemical heating packs or dry chemical heating packs (five to 10). You want the large kind made for rescue that heat up rapidly and not the smaller kind for putting in boots and gloves.
- Cloth bags to place between the heating packs and bare skin.
- Rescue/trauma shears for speedy removal of wet clothing.
- Sugar-rich foods or beverages.
- In winter, the kit should include ice picks, ice cleats for boots and a sled or toboggan for rescue.
It was the third-driest May in 151 years of records at the National Weather Service in Duluth.