Water and wastewater in winter weather

Water and wastewater in winter weather

In Nebraska, extreme winter temperatures can come on quickly and hang around for extended periods.  Those extended periods of cold can be hard on things, but what impact do they have on your septic system? Can they affect your well and your water system? And what can you do to limit any impact?

 A common misconception is that the bacteria in a septic tank produce heat as they work to digest the waste within your wastewater system.  The truth is that the digestion process does not produce heat and once temperatures in a tank reach approximately 39 degrees, almost all of the bacteria working in the tank comes to a halt. Once the bacteria stop working the wastewater is not treated properly. So it is very important to keep your tank working and to prevent water within the tank from freezing.

 Normal winter conditions usually do not pose a problem for the tank because the soil and groundcover, such as grass, helps to serve as a natural insulator.  Some newer septic tanks are installed with a layer of styrofoam-like or other similar insulation on the lid of the tank.  Natural or added insulation may not be enough to protect the system when “normal” turns to “extreme."

 Extreme winter temperatures are of the most concern to septic systems when there is not snow on the ground.  Snow cover can serve as a natural insulator protecting the tank and other system components from direct exposure to those extreme temperatures.  However, with or without snow cover, once those very cold temperatures stick around, the following tips can help prevent your tank from becoming an expensive igloo:

 Spread warm water (hot is even better) use throughout the day and the week. For example, run the dishwasher in the morning and then do a load of laundry in the evening. Baths or showers also help to introduce warm water to the system.  As always, spread the use out so as not to overload your system.  And never run water constantly.

  • Do not compact the soil over your drainfield.  Driving over your drainfield or doing other activities that can compact the soil should never be done.  However, these type of activities in the winter can force frozen soils into the drainfield. Those soils can cause the system to “back-up” or the drainfield to become broken or clogged.
  • If you are traveling for the holidays or for a winter vacation, ask a friend to stop in daily to run a load of laundry or dishes. 
  • If you migrate south for the winter months or have a seasonal residence you may want to consider hiring a certified professional to install a tank heater or add insulation around the tank. 
  • Next fall, consider spreading a thick layer of mulch (8-12 inches) over the tank and other system components to help protect the system from periods of extreme cold. 

 A water well is generally less susceptible to periods of extreme cold. The well pump is most at risk to during extreme cold temperatures.  If your well pump is within an aboveground well house, make sure that the house is insulated.  The other key to protect your water system is to close the shut off valve for outdoor hydrants to prevent the water from freezing within the hydrant and distribution pipes. This can cause pipes to rupture or create other issues in your system. And as always, disconnect hoses from hydrants, especially those that are attached to your home’s water system. 


This article was reviewed by Sarah Browning

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