This ice strength and safety information is presented for the benefit of ice anglers and other winter sports people recreating on iced-over bodies of water.
The figures in the table below are for clear, blue ice on lakes and ponds. Reduce strength values 15% for clear blue, river ice. Slush or snow (white) ice is only one-half the strength of blue ice and can be very treacherous. "Honeycombed" ice, which occurs in the spring or during major winter thaws as the ice is melting, is the most dangerous ice, and best avoided unless the angler is certain there is a safe layer of solid ice beneath the honeycombed surface.
Anglers should also be aware that many lakes and ponds contain spring holes and other areas of current that may create deceptively dangerous thin spots in areas that are otherwise safe. Always use caution, and don't venture out onto unfamiliar waters without checking ice thickness frequently.
How can you tell if ice is safe?
Ice Thickness and Strength
|Ice Thickness (inches)||Permissible Load (on new* clear/blue** ice on lakes or ponds)|
|2" or less||STAY OFF!|
|4"||Ice fishing or other activities on foot|
|5"||Snowmobile or ATV|
|8"-12"||Car or small pickup truck|
|12" - 15"||Medium truck|
|*New ice is stronger than older ice.|
**White ice or “snow ice” is only about half as strong as new clear ice. Double the above thickness guidelines when traveling on white ice.
There are no guarantees. Always consider ice potentially dangerous. Assess ice safety by using an ice chisel to chop a hole in the ice to determine its thickness and condition. Make sure you continue to do this as you go further out on to the ice, because the thickness of the ice will not be uniform all over the pond or lake. Be aware that ice tends to be thinner on lakes and ponds where there are spring holes, inlets or outlets. Don't venture onto ice-bound rivers or streams as the currents make ice thickness unpredictable.
What if you, a companion, or pet fall through the ice?
As with any emergency, don't panic! Call for help if there are people nearby. While it doesn't take long for the cold water to start slowing your physical and mental functions, you have more time than you might think; typically 2-5 minutes and perhaps longer if you are in good, physical condition. Air will remain trapped in your clothes for a short time aiding your buoyancy. Kick your legs while grasping for firm ice. Try to pull your body up using "ice pins" that should be hanging around your neck. Once your torso is on firm ice, roll towards thicker ice. This will better distribute your weight. Remember that ice you previously walked on should be the safest. After you reach safe ice, don't waste precious time, you need to warm up and dry out. If you are in a remote area, this means getting to or starting a campfire. If you are in a more urban setting get to a car or house. Once there, get out of wet clothes, change into dry clothes to get warmed up and seek advice from your physician on medical attention. You need to warm up quickly to prevent hypothermia.
If a companion falls through the ice remember the phrase "Reach-Throw-Go" If you are unable to reach your friend from shore, throw him or her a rope, jumper cables, tree branch, or other object. If this does not work, go for help before you also become a victim. Get medical assistance for the victim immediately.
When walking on or near ice, keep your pets on a leash. If a pet falls through the ice do not attempt to rescue the pet, go for help. Well meaning pet owners can too easily become rescue victims when trying to assist their pets.
Outdoor recreation activities on the ice is a safe pursuit. By using a little common sense, these activities will stay that way.
For other ice safety tips and winter weather preparedness, check the Massachusetts Emergency Management Agency website.