By Captain Stephan Reckie, Loon Lake resident
Hypothermia occurs when your body gets cold enough so that its core temperature drops below 95 degrees, less than 4 degrees below normal body temperature. It’s a very real possibility for anyone fishing or boating on our local bodies of water all year round, where water temperatures are frequently below 80 degrees. Being around water in the winter introduces another safety variable – ice.
Cold water conducts heat away from your body 25 times faster than air of the same temperature. Within minutes, your core (brain, heart, lungs, and other vital organs) temperature begins to cool and your body responds by trying to retain as much heat as possible to keep the core functioning. The flow of blood to the arms and legs is reduced and your body tries to generate heat by shivering.
Shivering doesn’t produce enough heat to make up for the heat lost to cold water. Your body has limited reserved energy and your survival depends on making those reserves last as long as possible. If your core continues to cool, your body stops producing heat and your shivering stops. As your brain cools, its functions become impaired. You will eventually become confused and your muscles will become increasingly stiff until you are unable to move. If your body continues to cool, you will lapse into unconsciousness.
The 1-10-1 Rule
According to the Cold Water Bootcamp (www.coldwaterbootcamp.com/pages), 1-10-1 is a simple way to remember the first three phases of cold-water immersion and the approximate time each phase takes.
1 – Cold Shock. Upon contact with cold water, you will experience an initial deep and sudden gasp followed by hyperventilation, which can be six to ten times faster than normal breathing. You must keep your airway clear or you can inhale water and drown. Typically, this cold shock passes in about one minute. During that time, you must concentrate on avoiding panic and gaining control of your breathing. Wearing a personal flotation device (PFD) during this phase is critically important to keep you afloat and breathing if you are submerged.
10 – Cold Incapacitation. Over the next 10 minutes, you will lose control of your fingers, arms, and legs for any meaningful movement. Head towards shore or shallows quickly, but if that isn’t possible, keep your head above water to wait for rescue. Swim failure occurs within these critical 10 minutes and if you are in the water without a lifejacket you will likely drown.
1 – Hypothermia. Even in ice-cold water, it could take approximately one hour to become unconscious due to hypothermia. If you understand the aspects of hypothermia, techniques of how to delay it, can self-rescue and call for help, your chances of survival and rescue will be dramatically increased.
Your survival also depends on many factors such as water temperature, your age and physical condition, how you behave while in the water, the amount of insulation provided by your clothing, and your mental attitude. By taking the proper steps you can extend your survival time and increase your chances of being rescued. Use some means of flotation so you don’t have to use energy to keep yourself afloat. The best means of staying afloat is a PFD as it will keep your head and neck out of the water, which is where half of your body’s heat loss will occur. Remember that even the very best PFD is ineffective if you don’t wear it while on or near the water.
Measuring Ice Thickness
According to the Minnesota DNR website (www.mndnr.gov/icesafety), the most important thing to know about ice safety is that ice thickness is not the same across a body of water. You should always check the thickness of the ice in more than one area if you plan on crossing a body of water or staying on it for any amount of time. To be safe, you should measure the ice yourself with any of the following tools:
An ice chisel is a long metal rod with a sharp blade at one end. You drive this chisel into the ice to dig a small hole. Once you’ve reached the water, you can measure the depth with a tape measure.
There are several types of ice augers: hand, electric, cordless drill bit, and gas. A hand auger is the cheapest, but you’ll have to dig through using your strength. Once you’ve dug a hole with an auger, use a tape measure to check the ice.
Once you’ve measured the ice, you will want to know if it is safe enough to be on. The strongest ice is clear/blue and found over still waters. Since white/gray ice is much weaker, you should only consider traveling on clear/blue ice. If you are crossing a river, that ice is about 15% weaker than over non-running water.
Guidelines for Clear/Blue Ice
Below are some suggested guidelines for clear/blue ice thickness:
3 inches or less – Stay off; this ice is unsafe to walk on
4 inches – The ice is usually thick enough for ice fishing or other activities on foot
5 inches – You can travel on the ice with a snowmobile or ATV; or you can travel on foot as a group in a single file line
8-12 inches – This is the recommended amount of ice thickness for a car or small truck
12-15 inches – The ice can typically handle the weight of a medium-sized truck
Ice Areas to Avoid
When ice is white/opaque it is only about half as strong as clear/blue ice. As such, if you plan on traveling over white/opaque ice, it should be twice as thick. Use extreme caution over white ice.
When ice is gray or white/mottled gray, you should avoid it. These types of ice are the weakest and unsafe for any kind of travel or activity.
If you see bubblers (devices that bubble water to protect docks), don’t walk on ice near them. Bubblers can make ice weak in the surrounding area. Also, be wary of ice covered in snow; snow may be hiding open water or cracked ice. Always carry a portable flotation device in case you or someone else falls through the ice. Bring ice picks and keep them close; they can be used to pull yourself out of the water if you fall through. The best system to use is the buddy system, so bring a friend.
Vehicles on Ice
If the ice is thick enough for parking, move your vehicle every two hours to prevent sinking. Make a hole near your vehicle; if water begins to overflow, move your vehicle immediately. Park vehicles at least 50 feet apart and avoid areas where other vehicles have parked previously.
Falling Through the Ice
If you fall through the ice remember the 1-10-1 rule. As soon as you can, kick your legs, grasp for nearby ice and get yourself horizontal on it. If you have ice picks or long metal nails, you can use them to pull yourself onto the ice. Once you get yourself out of the water, roll toward thicker ice. As soon as you are off the ice, work fast to prevent hypothermia.
If someone else falls through the ice, and you can’t reach them from shore, the first step should be to throw them a rope, tree branch, jumper cable, or any other long object. If nothing is available, you should go for help and call 911. Once the person is out of the water, you will also want to work fast to prevent hypothermia.
If your pet falls through the ice your first instinct may be to help them. However, if the ice isn’t thick enough for your pet, it won’t be for you, so get help and call 911.
Keep all the above suggestions in mind when you are out on the water, whether frozen or not, and please stay safe and warm!