Skip to main content

Boreal Community Media

Thin Ice? Think Twice.

Nov 26, 2022 07:19AM ● By Editor
From the National Weather Service - Duluth MN and the Minnesota Department of Natural Resources • November 26, 2022

While the cold temperatures in mid-November caused ice to form on some inland lakes and rivers, warmer temperatures this weekend will cause that ice to weaken and break up. This early season thin ice is NOT yet safe to venture on just yet. If you must, be prepared to self-rescue from the cold water.

MN DNR general ice thickness guidelines

ice thickness guidelines

The DNR does not measure ice thickness on Minnesota lakes. Your safety is your responsibility. Learn about the different ways to check ice thickness before heading out.

Temperature, snow cover, currents, springs and rough fish all affect the relative safety of ice. Ice is seldom the same thickness over a single body of water; it can be two feet thick in one place and one inch thick a few yards away.

Ice thickness guidelines for new, clear ice only.
UNDER 4"Stay off
4"Ice fishing or other activities on foot
5" - 7"Snowmobile or small ATV
7” – 8”Side-by-side ATV
9” – 10”Small car or SUV
11” -12”Medium SUV or small truck
13”Medium truck
16” -17”Heavy duty truck
20”+Heavy duty truck with wheellhouse shelter

Our recommendations are based on average equipment weight and assume solid, clear ice. You are responsible for knowing the weight of your vehicle, equipment, and bodies.

Many factors other than thickness affect ice strength, including air temperature, wind, snow, streams, narrow areas or bottlenecks, sun, shade, fish communities, plant decay, and more. When a layer of snow melts and refreezes on top of lake ice, it creates white ice, which is only about half as strong as new, clear ice. Double the above thickness guidelines when traveling on white ice.

Learn more about white ice and other common factors that can cause ice to be unsafe.

Learn more about how to check ice thickness.

Frozen lakes are not parking lots

several cars fallen through iceCars, pickups or SUVs should be parked at least 50 feet apart and moved every two hours to prevent sinking. Stationary loads (longer than two hours) require thicker ice than the standard guidelines. See the table below for stationary loads of more than two hours but less than seven days.

Tip: Make a hole next to the car. If water starts to overflow the top of the hole, the ice is sinking and it’s time to move the vehicle.

Minimum ice thickness for stationary/parked loads up to 11,000 lbs*

Load/Situation

Minimum Effective Thickness (inches)

Person standing

6

Snowmobiles (maximum weight machine + rider <1,100 lbs)

10

Loaded vehicle >1,100 lbs but <2,200 lbs

13

Loaded vehicle >2,200 lbs but <4,400 lbs

16

Vehicle >4,400lbs but <6,600 lbs

18

¾ ton 4x4 vehicles (maximum GVW of 11,000 lbs)

22

*The stationary load recommendations are from a publication by the government of Alberta, Occupational Health and Safety. Best Practice for Building and Working Safely on Ice Covers in Alberta, Jan. 2013  PDF (link is external).

Boreal Ship Spotter - larger view here