We have all seen the signs warning us of the dangers of walking and climbing the ice shelf mounds. They begin forming at Wasaga and its beaches in late January and early February, and typically stay around until late February. That warning sign, for me at least, brings on dreams of the horror of being swallowed up by one of the ice shelf tubes.
Similar ice shelves form on the eastern shores of all Great Lakes. Even on lakes like Michigan and Huron, which freeze over almost totally at times, winter storms will break up the ice and shelf mounds will form.
The transformation of the lakeshores in winter is amazing. They look like miniature mountain ranges, piled up by the waves of the lake, rising to 4.5m to 6.0m above the surrounding surfaces. The waves crash on to the floating ice along the shore, and the water then freezes.
It is very important to note that the ice shelves are not attached to the lake bottom, but float above it.
Although the ice appears solid and stable to casual observers, it is actually pocketed with hidden air holes, cracks, thin spots and faults. These are surrounded by ice or drifting snow so are made invisible to visitors.
Any visitor who risks venturing onto these dangerous shelf mounds could easily fall through a shaft or hole, and face deadly consequences.
The shafts can be up to one meter in diameter and over 4.5m deep, leading to the unbearably cold water below.
Many of us have heard of hypothermia. It usually sets in after no more than 30 minutes. Your body loses heat faster than it can produce it, cooling the organs in its core and leading to loss of consciousness.
However, should you fall into an ice shaft you would be quite apt to drown before hyperthermia would set in.
The following is a scenario of could happen to you if you unexpectedly fall into an ice shaft or water hole and are immersed in the icy cold water.
The initial “cold shock response” will make you gasp instinctively for air. You “hyperventilate”, which may result in your swallowing too much water and quick death by drowning.
There may also be changes in blood pressure, heart rate, and heart rhythm which, depending on the current state of your health, can likewise result in an almost instant death.
Heavy winter clothing may slow down some of the effects, but may also inhibit your movements once it soaks up enough freezing water.
With an ice hole, you may be lucky if someone can reach a life saving device such as a ring on a rope and get you to hold on to it until you are pulled to safety. However, falling into an ice shelf mount tube is a totally different situation.
Within minutes following your immersion in cold water, your muscles and nerves in arms and legs cool, causing a marked loss of manual dexterity, hand grip strength and speed of movement, which will make it impossible to pull yourself out of the water or even keep your head above water to prevent yourself from drowning.
Without ice climbing gear, there is no chance of climbing back up the long, slippery ice shaft. Quick rescue is virtually impossible, and the mission will become one of recovering your deceased body.
Once in the bottom of the shaft, chances are that you will be swept away from it by the water moving under the shelf. The sides of the shaft are slippery so hands can not grip the ice and feet cannot touch the bottom of the lake. By this time, you are probably already dead.
If you are lucky enough to be rescued, you are still in danger from collapse of arterial blood pressure, leading to cardiac arrest. Cold water may have damaged your lungs, and heart problems may develop as cold blood is released into your body core.
Records of drownings in the Great Lakes do not differentiate as to the circumstances. If you drown, you are listed as a drowning victim, regardless of the reason or of how you drowned. Therefore, no statistics are available of drownings on ice shelves.
A Twitter video that showed a man who had fallen through the shelf ice at Chicago on Lake Michigan was publicized on January 26th, 2020 by NBC as well as by the Great Lakes Surf Rescue Project. The video showed him struggling in just hip-deep water, which he had mistaken to be part of the beach because of the dirty sand on top of the ice.