University of Minnesota Extension, Published January 12 2012
U of M offers tips to prevent freezing septic systemsST. PAUL — Freezing problems with septic systems may be more common this year because a lack of snow cover across Minnesota exposes existing system inadequacies as temperatures dip lower.
Snow serves as an insulating blanket over septic tanks and soil treatment areas. According to Extension staff at the University of Minnesota Onsite Sewage Treatment program, lack of snow allows frost to go deeper into the ground, potentially freezing system components. The good news is that frost depths are still fairly shallow statewide.
The most important concern is cold air entry into the system. Open, broken and uncapped risers or inspection pipes allow cold air into the system and can cause the system to freeze. Other causes of a frozen septic system include outdated or overloaded systems, the absence of vegetative cover over the system, slow leaking plumbing fixtures, compacted soils, and irregular water use.
Follow these tips if you are concerned about your system freezing:
- Place an 8- to 12-inch layer of mulch over the pipes, tank and soil treatment area to provide extra insulation.
- Make sure all access points to your system are covered. Sealing them and adding insulation is a good practice.
- Use water, the warmer the better during cold snaps. Run the dishwasher. Take a hot bath. Spread your warm laundry schedule to one load a day instead of doing it all once a week. Do not leave water running; this will hydraulically overload your system.
- Fix any leaky plumbing fixtures or appliances in your home. This will help prevent freezing problems and increase the longevity of your septic system.
If you experience a frozen septic system, contact a Minnesota licensed septic system professional immediately to identify the cause of freezing and provide relief. Many maintainers and installers operate steamers and high-pressure jetters to thaw system piping. Other methods used to help fix a freezing problem include adding heat tape and/or tank heaters.
Cameras can be sent down the pipes to determine where the freezing is occurring and if repairs are needed. If the soil treatment system is full of ice, or there is evidence of leaking, there is no need to thaw the lines leading to the treatment area, as it cannot accept liquid until the area is thawed in spring. Unless the cause of freezing is corrected, the system is likely to refreeze next winter, so it is essential to identify and correct the problem.
In the long term, having a properly designed, installed, maintained and operated system is your best insurance against freezing issues. Do not put off repairing your system if you know of problems. The current lack of snow cover may expose these problems and create costly and difficult circumstances.
To find a licensed septic system professional, visit the Minnesota Pollution Control Agency website at http://bit.ly/tA8RtQ.
Find more information about winter septic systems problems at www.septic.umn.edu/factsheets/freezingproblems. Other septic system information is available at www.septic.umn.edu.