December 13, 2001

Lake and River Ice Is Not Safe

It is not advisable to venture out on the ice on local rivers, lakes and sloughs. "There have been a few cold nights, but not enough to allow safe ice to develop," according to George Maher, North Dakota State University Extension Service safety specialist. "At least a week of temperatures lower than 20 degrees are needed to make ice that is strong enough to be safe. It has not been cold enough long enough, for safe ice to develop. Increases in daily temperatures will slow the development of safe ice or even reverse it, causing safe ice to become dangerously thin as it melts."

Children must be told and convinced that it is not safe to venture out on the ice. Because of the thin ice, adults will not be able to rescue children who venture out on the ice and get into trouble. Ice must be at least 4 inches thick to support adults. Two inch thick ice might support children but it will not allow adults to rescue them if the child breaks through.

Thin, white or cloudy ice is not safe. Safe ice is clear to bluish in color and at least;

• 4 inches thick for people on foot.
• 5 inches thick for snowmobiles.
• 10 to 12 inches thick for small to average sized automobiles.
• 12 to 16 inches thick for heavier pickups and vans.

Falling through the ice is life threatening. "The combination of shock and the extremely cold water will quickly bring on hypothermia," Maher says. "Hypothermia is when the body loses heat faster than it can replace it. The body temperature falls quickly as the cold water saturates the clothing and chills the skin. Death is almost certain when the core temperature of the body has dropped to the point where body heat can not be maintained. Hypothermia is fatal when the heat loss cannot be reversed. Supplemental heat must be supplied until the heat loss is reversed and normal body temperature is stabilized."

When the victim can not come back up through the same hole he fell into, drowning is certain. It is nearly impossible to break through the ice overhead. For the victim and would-be rescuers, this is a sheer panic situation. "Do not go out on the ice, river, pond, or lake if the ice is less than 4 inches thick," Maher says.

If it is absolutely essential to go out on thin ice, in a rescue attempt for example, follow these procedures;

• Never go out alone, always have an observer watching from shore. The observer must be capable of rescuing you or responsible for getting help, immediately. It is better to have several helpers present for immediate help.
• Carry a long pole with you in a flat, horizontal position. A good 2 x 4 at least 10 feet long may be sufficient for the average person. The long pole will bridge across the hole and give you something to hold onto when you fall through the ice.
• Another lifesaving possibility is a length of rope. One end is to be tied to something solid such as a vehicle or tree on shore, the other end tied around your waist before going out on the ice.

Under-water springs can also keep ice from becoming thick enough to be safe. They can be found in rivers and streams as well as ponds or lakes. Moving water does not freeze.

Pond or lake ice usually forms earlier than river or stream ice. The current of the stream or river prevents ice from thickening as fast as lake ice. So, extra care is essential when going out on river or stream ice.

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Source: George Maher, (701) 231-8288, gmaher@ndsuext.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu

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