top of page

What to Do if Your Septic Tank Freezes


Septic tank truck on a countryside field full of snow.

Winters in Canada bring along some frigid temperatures. It can even reach -30ºC! That's low enough to freeze your septic tank and entire septic system. It can be quite a buzz kill when you're already trying to survive such chilling temps.

We want you to be prepared so that you know what to do when that time comes. Read on to find out!

How Can My Septic Tank Freeze?

It's not uncommon for a septic system to freeze in the cold winters here in Canada. Septic tanks are supposed to be buried beneath the frost line, but even still, they are susceptible to freezing for a few reasons.

Frozen Pipes

Septic pipes leading away from homes can freeze and keep warm water from reaching the tank. When warm water can’t make it to the tank due to frozen septic lines, it allows the contents of the septic tank to freeze.

Not Enough Use

Another common reason for a frozen septic tank is that it doesn't get enough use in cold temperatures. People that flee Canada for warmer weather often come home to find a frozen septic system.

Using your septic system keeps that warm water we talked about flowing into the tank. When that's not happening often enough, your septic can freeze.

Even something as simple as going to work and not being able to use the septic can be long enough to freeze it.

Eroded Soil

The frost line changes as the soil washes away. Your tank may be exposed to colder temperatures for that reason.

The less insulated your septic tank is, the more the opportunity for it to freeze. This is also true for removing snow!

You may think you're doing good by shovelling snow from your yard. In actuality, the snow is an excellent insulator for your tank.

Extended Cold Weather

Sometimes, it's just too cold for too long, and your septic system can't handle it. There isn't anything you can do about the weather and how long the temperature stays below freezing.

What You Shouldn't Do

No one wants a frozen septic system, so it may sound like a quick fix to try to handle it yourself. However, this is how many homeowners end up in trouble.

Problems arise when antifreeze is added to the septic system. Not only is it toxic, but it contains ethylene glycol, which can disrupt the leach field.

A few other things you shouldn't attempt to do are...

  • Pump the septic tank out yourself

  • Fill it with hot water

  • Start a fire over the septic tank


Call A Professional

The right thing to do is to call a professional to assess and address your frozen septic tank. They have the right tools to get the job done correctly, such as a steam unit.

This unit can provide heat to an entire site for the winter months by using the steam-heated ruffneck heater. It can also provide steam to thaw frozen lines and tanks.

High County Vac Services can help you this winter season. Learn about our septic services!


bottom of page