Frozen rivers and lakes

Crossing a frozen river or lake can save distance, but it is one of the most common ways to die in winter. Rivers are more dangerous than lakes: the current thins the ice from below and you cannot see it from above.

• Avoid crossing whenever there is another route.

• Minimum thickness for walking: 4 inches (10 cm) of new, clear ice, according to the MN DNR. White or snow-covered ice holds about half as much: it needs twice the thickness.
• Avoid: dark, gray, or water-covered ice; areas near drains, river inlets and outlets, bridges, and protruding logs or rocks; ice covered with new snow (it insulates and hides thin ice).
• If you have to cross: one at a time, spaced apart, with your pack unbuckled, probing with a pole, and with a rope if you have one. Wear ice picks around your neck.
• If you fall in: turn toward where you came from, arms on the firm ice, kick, drag yourself out, roll away from the hole (full steps in chapter 13). Remember the 1-10-1 rule: you have about 10 minutes of useful strength.