The Lowdown on Fabric Softener and Your Septic System

Many septic owners are extremely careful about what they flush into their systems, making sure to only flush items on the approved list. For many, one of the most surprising “banned” items is fabric softener. What’s not to love about fabric softener? It leaves your laundry cuddly soft, smelling fresh, and static-free. But when you consider that, like any other chemical, it can have a devastating impact on your septic system (not to mention you and your loved ones), you will realize it’s not as innocent as that cuddly bear would lead you to believe. Here’s a look at what fabric softeners are, how they impact your septic system, and safe alternatives you can use instead.

What are Fabric Softeners?

Fabric softeners come in two forms – liquid that is added during the rinse cycle and dryer sheets. First developed in the early 1900s to soften fabrics after they’d been dyed, liquid fabric softeners initially contained soap and oils, like tallow (rendered animal fat). Today, they are a petroleum-based cocktail containing a host of chemicals, emulsifiers, fragrances and artificial colors. Many contain silicon, acids, and quaternary ammonium compounds (commonly referred to as quats). Added during the rinse cycle, the fibers of your laundry are coated with a thin layer of these chemicals. Dryer sheets, which were introduced in the 1970s, are woven sheets of fibers coated with heat-activated fabric softener that transfers to your laundry when tumbled in the dryer. 

It may be tempting to overlook the fact that fabric softeners coat your family’s laundry in a slurry of cocktails when the end result is soft, static-free, fresh-smelling clothes. However, there are a lot of drawbacks to using fabric softener that are completely unrelated to your septic system. The use of either liquid fabric softeners or dryer sheets has been linked to many significant health risks, including dermatitis, asthma, reproductive problems, and even cancer. Fabric softeners also endanger your family by coating your laundry in flammable accelerants. Fabric softener builds up on the fibers of your clothes, so the longer you use fabric softener, the more flammable your laundry will be.

The Effects of Fabric Softener on Your Septic System

Fabric softeners, just like other household cleaners and chemicals, can have devastating effects on your septic system. The impact on your septic system is two-fold – the chemicals within fabric softener attack your system’s ecosystem as well as interfere with the tank’s physical functioning. The quats in fabric softener are particularly troublesome for your septic system. They are not only antibacterial, enabling them to kill off the good bacteria in your system’s tank, but they also contain nitrogen. Nitrogen concentrations in most domestic wastewater is between 50 and 60 milligrams per liter (mg/L), and the typical septic system is capable of removing 90% of these. Increasing this concentration by regularly using fabric softener means increasing the levels of nitrogen passing through your system, and ultimately more nitrogen finding its way into the groundwater. Why is this bad? Nitrogen runoff – whether from agriculture, landscaping, or septic systems – is the leading contributing factor to harmful algae blooms that are a growing problem impacting Ohio’s drinking water. 

Fabric softeners are also petroleum-based, as in oil-based. Pouring fabric softener into your washing machine is like pouring a fats, oils, and greases (FOGs) down the drain. Fabric softeners directly add to the layer of scum floating on the surface of your tank’s effluent. If the scum layer becomes too thick, it will be able to flow into your drainfield, potentially causing damaging clogs or even catastrophic system failure. Fabric softeners also contain emulsifiers to prevent the oils and chemicals from separating in the bottle. Once these emulsifiers find their way into your septic tank, they interfere with the tank’s natural settling process, preventing the solids from settling to the bottom and the FOGs from rising to the top. This allows solids to remain suspended in the effluent that will flow out into the drainfield, which is not designed to handle solids. Clogs may occur, which again may damage the system or even lead to whole-system failure.

Safe Alternatives to Fabric Softener

We understand the appeal of soft, fresh-smelling, static-free laundry. Luckily, there are safe alternatives (both for you and your septic system) to using chemically-laden, petroleum-based fabric softeners to achieve these results. Distilled white vinegar is a popular choice, offering great solutions to many common laundry woes. A half-cup added to your washer’s final rise cycle will naturally soften and deodorize laundry without leaving a residue. Instead of using dryer sheets, dryer balls made from wool, aluminum, or even silicon will help prevent static from building up in your laundry. If you enjoy the fresh scent fabric softener adds to your clothes, you can instead add 10 drops of your favorite essential oil along with the vinegar in the rinse cycle or even apply them directly to the dryer balls.

If you have used fabric softener with your septic system, keep a keen eye out for signs of septic system failure. Lush grass above or around your system, foul odors in and around your home, or gurgling drains are all signs that your system is in trouble. If you notice any of these signs, contact us to schedule a service visit right away.

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