Top Things You Should Never Flush—Ever!

Never Flush

We spend a lot of time educating septic owners about the perils of flushing things they shouldn’t into their septic system. Because there’s so much attention given to septic systems, most people make the mistake of thinking they don’t have to worry about what they flush into a public sewer. Far too often, people treat their toilets and kitchen sinks (especially if they have a garbage disposal) like trash cans. Sadly, this can lead to some significant complications and expensive repairs, both in your home and beyond. Here’s our list of the top things you should never flush—ever! You may be shocked at some of the items that are included. Let us know in the comments which item most surprised you!

Fats, Oils, and Greases (FOGs)

In the septic world, flushing fats, oils, and greases (FOGs) down your drain can lead to clogs in your plumbing pipes and septic tank baffles. They also contribute significantly to the scum layer in your septic tank, which can lead to disaster for your drainfield. Not too surprisingly, similar issues arise when FOGs are flushed into sinks leading to the city sewer. FOGs may be liquid when hot, but as they cool—as they do when they enter your home’s plumbing or the sewers—they solidify and collect on surfaces. This can cause significant clogs, damage to equipment, and even environmental contamination. Many people are also surprised to learn the food we put down the garbage disposal contain a significant amount of FOGs. Instead of flushing these down the drain, put FOGs into your garbage. We often recommend collecting FOGs in small containers (empty milk jugs, food jars, etc.) to seal and put into the trash.

Don’t Flush Disposable Hygiene Products

Disposable hygiene products, even those that claim to be “flushable” should never find their way into your pipes. These can create massive clogs within your home’s plumbing or in the pipe leading from your home to the sewer (which you are responsible for maintaining should something go wrong). They can also create massive headaches at the treatment plant. Disposable hygiene products that you should never flush include:

Bathroom Cotton

Bathroom cotton is a bit of a catch-all category and includes small items that you may use for personal hygiene or first aid, like:

  • Cotton balls
  • Q-tips
  • Bandages or bandage wrappers
  • Tissues or paper towels

These items, though small, do not dissolve in water and can cause significant clogs in your plumbing. They can also jam up machinery at the treatment plant. People are often surprised that tissues and paper towels are included in this list. Afterall, they both closely resemble toilet paper, but unlike toilet paper, they are specifically designed not to dissolve in water.


Toiletries most often flushed down the toilet include dental floss, condoms, and contact lenses. Each of these create significant risks for your plumbing and the environment. Dental floss often collects in the bends of your plumbing, creating nasty tangles that lead to terrible clogs in your pipes. Though condoms are typically made of latex, which is a natural material, they do not easily break down. Instead, they find their way to our water sources, where they can take as long as 30 years to biodegrade. Contact lenses, though small, create a different kind of environmental problem when they are converted to microplastics at the wastewater treatment plant. Each of these toiletries, and others like them, should be placed in the garbage, rather than flushed down the toilet.

Chemicals & Hazardous Waste

In addition to potentially corroding the plumbing pipes within your home, chemicals flushed down the drain can cause significant environmental problems. Wastewater treatment plants are not equipped to remove these toxic chemicals, which often end up back in our drinking water. As a side note, storm sewers typically lead directly to water sources, so flushing chemicals or hazardous waste into storm sewers is also extremely bad for the environment. Chemicals that should never flushed include:

  • Auto fluids
  • Paints
  • Solvents
  • Sealants (silicone or latex caulk, plumber’s putty, etc.)
  • Paint thinners
  • Lawn chemicals
  • Poisons (bug killers, rat or mouse poison, etc.)
  • Prescription or over-the-counter medication

While some medications can safely be flushed down the toilet without contaminating the environment or the community’s drinking water, the best option for disposing of unused or expired medications is dropping them off at a drug take back site. Flushing medication into the wastewater treatment plant can cause significant health problems for the whole community.

Never Flush Pet Waste & Kitty Litter

We understand the logic of flushing pet waste down the toilet. Afterall, how much different can it be from human waste? But the reality is, because their diets are so different from ours, their waste does not break down the same. Kitty litter, even the brands that claim to be flushable, should also never go down the toilet. It can create clogs in your home plumbing or damage machinery at the wastewater treatment plant.

Supeck Septic is Northeast Ohio’s Trusted Septic Provider

As Northeast Ohio’s largest septic provider, Supeck Septic is passionate about protecting the environment, whether you’re flushing into a septic system or a sewer. Have you flushed any of these items into your septic system? It may be time to schedule a service visit.

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