A frost heave is the upward swelling of soil during freezing conditions due to the presence of ice under the soil that gradually grows towards the surface. The repetitious expanding and contracting of the ice causes the surface to rise or heave. This can occur on any surface medium that allows water to permeate the soil and then freeze. This
includes roads, sidewalks and foundations.
Frost heaves can occur in any northern state and Alaska is no stranger to this phenomenon. Canada has their fair share as well. So if you are traveling along the Alaska Highway in Canada or the hard-top roads in Alaska, look out for these large bumps. Areas of frost heaves can be repaired but until that occurs, there is usually a yellow warning sign in advance of a heave.
If you see such a sign, immediately slow down so that you safely cross over the heave. Don’t be in such a hurry that you ignore the warnings as this can result in damage that could interfere with your vacation. There really is no need to hurry up here in Alaska, particularly if you’re trying to get somewhere before dark, because the sun sets late, if at all!