Ice Safety

Don’t mess around with ice. It doesn’t matter if you’re a strong swimmer, in top physical shape, or an old hand in the North: going through the ice will kill you in minutes. Follow the rules below at all times, or you’re taking your life in your hands.

(Information on this page is courtesy of The Lifesaving Society of Alberta and the Northwest Territories.)


Check ice thickness.                The City of Yellowknife’s webpage offers useful Yellowknife Ice Thickness Measurements. The Yellowknife Fire Department does not recommend walking on ice in the Yellowknife area until the ice is a minimum of 6 inches thick.
Use only designated ice surfaces for recreation.                                                    Designated ponds for skating should be maintained by well-informed personnel and be regularly tested to ensure that the ice is thick enough and strong enough for recreational use.
Know the different types of ice.  Recommendations for ice thickness are based on clear, blue or green ice. White ice has air or snow within it and should be considered suspect. Ice that is a mixture of clear and white ice should be a minimum of six inches before walking on it. Conditions such as currents and water depths affect ice thickness. Sections of ice that are very close together can have very different thicknesses.
Always supervise children playing on or near ice. Insist that they wear a lifejacket, Personal Flotation Device (PFD) or thermal protection buoyant suit.
Have an emergency plan. Plan and practise what to do if someone falls through the ice.
Stay off river ice. Currents can quickly change ice thickness overnight. Different parts of the river will have different and dangerous ice depending on the water flow below.
If you drive on ice, have an escape plan. Open your windows, unlock your doors, and turn on your lights. This will help you to escape from your vehicle more quickly.
Never go onto ice alone. A buddy may be able to rescue you and/or go for help. Before you leave shore, tell someone else where you are going and your expected time of return.
Wear a snowmobile flotation suit or a lifejacket/PFD. A lifejacket over your snowmobile suit or layered winter clothes greatly increases your survival chances.
Avoid alcohol. Alcohol impairs your judgment and speeds up the development of hypothermia.
Avoid travelling on ice at night. Snowmobile-related drownings often occur at night as it is difficult to see open holes and weak patches in the ice.
If the worst happens and someone falls through, don’t panic! 

Anyone on or near the weak ice should slowly lay down. Tell the person in the water to kick and slowly ease their way out. Have them crawl or roll away from broken ice. Use a long reaching assist, i.e. a rope, stick or ladder. Once the person is out of the water, make sure you are both far enough away from the hole before you get close. Help the victim into dry clothes, into shelter, and treat for hypothermia.

Thickness Rules

3” (7cm) or less STAY OFF
4” (10cm) Safe for walking, cross-country skiing
6” (15cm) Safe for one snowmobiles
8”-12” (20-30cm) Safe for one car or small pickup
12”-15” (30-38cm) Safe for one medium truck (pickup or van)

Safety equipment:

  • ice picks
  • an ice staff
  • a rope
  • small personal safety kit (should include a pocketknife, compass, whistle, fire starter kit and cell phone)

Ice Myths vs Realities:

Myth:Ice forms at the same thickness everywhere on a body of water.

Reality: Ice is rarely uniform in thickness. It can be a foot thick in one place and only an inch thick just 10 feet away.

Myth:Thick ice is strong.

Reality: Thick ice can actually be weak, especially if it has frozen and thawed repeatedly or if it contains layers of snow or water.

Myth:All ice has the same strength at similar thicknesses.

Reality: Different types of ice have different strengths. Clear blue, black or green ice is the strongest. 4” (10 cm) of this ice should safely support one or two people. White or opaque ice should be at least twice as thick (8” or 20 cm) to safely support the same number of people.

Myth:Snow on top of ice makes it stronger and helps it to freeze faster.

Reality: Snow acts like an insulating blanket. The ice under the snow will be thinner and weaker. A new snowfall can also insulate, warm-up and melt existing ice. Ice with layers of snow may not support anyone.

Myth:Extreme cold means safe, thick ice.

Reality: A cold snap with very cold temperatures quickly weakens ice and can cause large cracks within half a day. A warm spell, on the other hand, can take several days to weaken the ice.

Myth:If you know where you are going and what the ice is like, it is safe to travel across the ice at night.

Reality: It is particularly dangerous to travel on ice at night. Ice conditions change daily and you will generally not be able to see hazards or warning signs at night.

Myth:The better you swim, the better your chances of rescuing yourself if you fall through ice.

Reality: After as little as five minutes, cold water begins to rob you of your ability to move your limbs. This makes it very difficult for you to get out of the water, no matter how well you can swim!