Most simply put, ice is tricky, and just because a lake or stream is frozen does not mean the ice is safe. A lake or stream appearing to be frozen can be very dangerous, and every year, people are injured or killed or property is lost or damaged when they do not respect it.
"Cold weather in late November formed ice on many South Dakota lakes and streams, but due to the accompanying snow, that ice did not develop into anything dependable," said Game, Fish and Parks Regional Law Specialist Dave Wicks of Watertown. "Recent warm temperatures have further weakened that ice, so it is important that people note that some of it is likely to be unsafe."
While the only absolute safety factor on ice is to stay off of it, doing so would prevent many of us from participating in some of our favorite winter activities, like ice fishing, hunting, trapping, skating, snowmobiling, snow-shoeing or cross-country skiing. Here are some tips to lessen your chances of a breakthrough:
? 2-inches of clear, solid ice is usually safe for one person walking.
? 4-inches of the same kind of ice is usually safe for ice fishing.
? 5-inches of the same kind of ice is usually safe for snowmobiling.
? 8-12 inches is usually safe for vehicles to be on ice, but driving should be avoided whenever possible. Traveling in a vehicle on ice, especially early or late in the season, can be very dangerous.
? New ice is usually stronger than old ice. As ice ages, the bond between the crystals makes it more dangerous and weaker even if melting has not occurred.
? Wind speeds influence ice formation. Light winds speed up the formation. Strong winds force water from beneath the ice and can decay the edges of the ice.
? Snow can insulate ice and keep it strong. It can also insulate it to keep it from freezing. When ice is covered by snow, great precautions need to be taken to determine ice thickness before starting any activity. Snow can also hide cracked, weak and open water areas.
? Slush is a danger sign. Slush indicates that ice is no longer freezing from the bottom. Slush also indicates weak or deteriorated ice.
? Ice can change with the surrounding climate conditions. Temperature, precipitation, wind speed, ice age and water depth and water quality are all factors that affect ice strength and thickness.
? If possible, one person should never check ice or attempt to rescue an ice victim because they could go from rescuer to victim very quickly.
? Individuals should wear a flotation device and ice picks when on questionable ice. They should also carry ice picks whenever on ice, as they may never know when they may need them to pull themselves out. Everyone should have a set. Two short lengths of broom handle or dowel with sharpened nails in one end and joined with a piece of string can be easily carried in a pocket.
? Before you head onto ice, check with a local bait shop, resort owner or local angler for known areas of thin ice or open water.
? If you must drive a vehicle, be prepared to leave it in a hurry. Unbuckle your seat belt and have a simple plan of action in case your vehicle breaks through. Some safety experts recommend the doors be left ajar and windows down for ease of exit.