Preventing Septic Systems From Freezing

When winter weather sets in, many people deal with the threat of frozen pipes. But what you might not know is that it's also possible for your septic system to freeze. And just as it's easier to prevent frozen pipes in and around your home before damage is done, it's also better to prevent your septic system from freezing if possible.

What causes the septic system to freeze?

One of the reasons why septic freezing is more rare than freezing of water pipes is that the breakdown of biological matter in the system generates warmth. This means that the more a system is used, the less likely it is to freeze. If you go on vacation and leave your home for a period of time, the lack of use can mean a lack of warmth generated in the system.

Homes with only one or two people in them, especially if they work and are out of the home for a large part of the day, may also not see enough septic system use to provide much warmth to the system.

By itself, low use isn't a problem. Septic systems freeze when this lack of use, and internal warmth, is combined with freezing conditions around the septic system. Winters where periods of cold weather cause frost to penetrate into the ground can create perfect conditions for septic freezing.

How can freezing be prevented?

You can prevent your septic system from freezing by fighting both causes. For addressing lack of warmth, try the following:

  • Use the system more frequently – take extra showers or run some hot water down the pipes each day, for instance
  • For long vacations, consider asking someone to housesit so your system remains in use
  • If you must be gone on vacation and can't keep the system in use, make sure you protect the septic field itself

To keep the ground around the septic system from freezing, there are also precautions you can take:

  • Watch for, and fix, any leaky parts of the system; leaking water can freeze and create ice dams that damage pipes
  • Keep an insulating layer of fluffy snow over the septic tank and, if possible, the line – to do this, avoid plowing or shoveling this area or driving over it
  • If the snow must be plowed or becomes compacted, thickly mulch the ground over the pipes, tank, and drain field with 8-12 inches of loose material such as straw or hay

What if the system freezes?

Unfreezing a septic system can be complicated, so it's best to call in a professional such as SOS Septic Inc. Don't add salt or antifreeze to the system yourself because you risk damaging your pipes and clogging your drain field. A professional can also help determine how to prevent the problem from recurring in the future; if your system froze even with the above precautions, you may need insulated pipes, a sewer heater, or other alterations to your system.