Ice Facts


    When is ice safe? There is no sure answer. Ice is tricky, and just because a lake or stream is frozen doesn't mean the ice is safe. 

    To understand the factors involved in the strength of ice, it's necessary to understand how ice forms on lakes and streams and a few of its physical properties. Here are points to consider, some based on research by the U.S. Army Cold Regions Research and Engineering Laboratory in New Hampshire.


You can't tell the strength of ice just by its appearance, the daily temperature, thickness, or whether the ice is or isn't covered with snow. Strength of ice, in fact, is based upon all four factors  plus the depth of water under the ice, size of water body, water chemistry, distribution of the of the ice, and local climatic factors.