Nature Note - Ice Safety
This past January, confused vacationers unknowingly drove their car onto the frozen waters of Lake Champlain by the Burlington Coast Guard Station. The vehicle quickly broke through and sank in the inner harbor. Fortunately, all of the passengers were able to escape unharmed and the car was ultimately moved to shore. While the group didn’t intend to drive onto the lake, their tale is a reminder to leave cars and trucks in the parking lot and always be cautious about venturing onto ice. Natural ice is a beautiful and intriguing phenomenon but it’s critical to be prepared before exploring it. The fluctuating temperatures of recent weeks urge caution. Widely varying temperatures that cause ice to thaw and then refreeze triggers honeycombed ice that is weak and unsafe. Below we offer some safety tips based on guidance from the Michigan Department of Natural Resources.
The safety of ice varies depending on a combination of factors including, thickness, temperatures over a period of time and on the day, depth of water under the ice, size of the water body, local weather fluctuations, and the extent of the ice. Ice is always changing and doesn’t freeze or thaw at a uniform rate. It can be thick in one spot and dangerously thin only a few steps away. New ice is usually much stronger than old ice. Direct freezing of still water makes stronger ice than that formed by melting snow, refrozen ice, or ice made by water bubbling up through cracks and freezing on the surface. Clear blue/black ice is the strongest. Milky white ice is formed by melted and refrozen snow and is porous and weak. Assume that ice covered by snow is unsafe. Snow slows the freezing process so the ice underneath will be thinner and weaker. Snow can also warm up and melt existing ice. Avoid slush ice. It’s half as strong as clear ice and indicates the ice is no longer freezing from the bottom. Ice near the shore is weakest. The shifting, expansion and buckling action of a lake or stream over the winter continually breaks and refreezes ice along the shoreline. Protruding logs, brush, or docks can absorb heat from the sun and weaken the surrounding ice.
Take the following precautions when going out on natural ice:
- Always observe ice first and test it before venturing out.
- Never go onto ice alone, let people know of your plans and timeframe, and dress for the conditions.
- Wear a life vest or some form of flotation device and bright colored clothing.
- Bring claws or an icepick, and take a spare set of warm, dry clothes in a waterproof bag.
- Take a charged cell phone for emergency use.
- Use an auger to test ice thickness.
- Remember no ice is entirely safe ice.
If you fall through:
- Try to remain calm.
- Don't remove your winter clothing. Heavy clothes won't drag you down, but instead can trap air to provide warmth and flotation. This is especially true with a snowmobile suit.
- Turn in the water toward the direction you came from - that is probably the strongest ice.
- If you have them, dig the points of the ice picks into the ice and, while vigorously kicking your feet, pull yourself onto the surface by sliding forward on the ice.
- Roll away from the area of weak ice. Rolling on the ice will distribute your weight to help avoid breaking through again.
- Get to shelter, heat, dry clothing and drink warm, non-alcoholic and non-caffeinated beverages.
- Call 911 and seek medical attention right away if you feel disoriented, have uncontrollable shivering, or have any other ill effects that may be symptoms of hypothermia (the life-threatening drop in the body's core temperature).