Ice Thickness

Updated March 20, 2023

The Ice Thickness Testing program has concluded for the 2022/23 winter season. It is no longer safe to be on frozen lakes and ponds, as there is noticeable thin ice and open water in many lakes across the region.

Each year, the municipality provides reports on ice thickness testing undertaken on more than 70 lakes throughout the region. This testing will continue next season.

This time of year, rising temperatures and snow cover on frozen bodies of water can increase the ice melt significantly each day. Residents are asked to take safety precautions for themselves and their families by avoiding any further recreation activities on frozen lakes and ponds, including walking, snowmobiling, and skating.

The Red Cross recommends the following:

• 15 cm for walking or skating alone
• 20 cm for skating parties or games
• 25 cm for snowmobiles

 See a complete list of guidelines from the Canadian Red Cross regarding ice safety. 

Frequently Asked Questions

What is the process for ice thickness testing?

For conditions where ice is just forming, a small hole is created in the ice at the shoreline. Equipment used will depend on ice thickness. Once the hole has been cut, a reading is obtained by hooking a graduated rod at the bottom of the ice. The reading is rounded down to the nearest centimeter and recorded in the Ice Thickness Report, along with general conditions such as visual signs of open water, shell ice (a thin layer that is formed on top of the water) and surface conditions.

If conditions permit, three testing holes are made at 16 metre (50 foot) intervals out from the shoreline in a random pattern using a 10 centimeter (4") ice auger or other appropriate equipment. A reading is taken at each hole, again rounding down to the nearest centimeter and recorded in the Ice Thickness Report.

When does ice thickness testing begin?

Testing will begin once ice has formed and it is safe for staff to begin testing.

How thick does the ice need to be to be considered safe? 

The Red Cross recommends the following:

• 25 cm for snowmobiles
• 15 cm for walking or skating alone
• 20 cm for skating parties or games

How many lakes and ponds does the municipality test? How are these sites selected?

Halifax Regional Municipality tests 70 lakes and ponds throughout the region. Site locations include municipally owned land with safe access points and which fall within a reasonable travel distance from site to site given available staff and resources.

How often are the sites tested for ice thickness? What causes delays in ice testing?

The objective is to test the ice once per week Delays can be caused by a variety of factors, including the following:

• Thin ice and open water where an acceptable reading can not be obtained
• The color of the ice can give a visual of its thickness (for example, black ice indicates that the ice is thin)
• Weather can limit our ability to reach and test sites accurately
• Availability of trained staff due to winter weather events (clearing streets and sidewalks may need to take priority)

Does the municipality test ice thickness during winter weather events?

No, during winter weather events, staff are addressing other priorities such as clearing streets, sidewalks, park parking lots, multi-use pathways, and regional parks 

Why doesn’t the municipality report measurements under 15cm?

Any reading under a safe measurement of 15cm may create a false sense that the ice is safe for use as ice thickness can change quickly with temperature, waterflow, etc.

Generally, how soon after an ice thickness test can residents expect the schedule below to be updated?

If conditions allow, testing will be done once per week and posted on the same day.

What other lake or pond conditions might impact ice formations?

Areas where water runs into a pond or lake may not form ice or have thin ice in that area.

Additional Resources

Halifax Search & Rescue

Canadian Red Cross