Why Does My Septic Tank Smell?

Your septic tank will release unpleasant odors for many reasons and all of them signal trouble. You might notice a sewage smell inside your home, or you may smell sewage outside. Express Septic Services can help no matter where you smell the odor or what the cause is. Here are some reasons why you can smell your septic tank. Don’t panic just yet. The fix may be a simple one.

Drains Are Too Dry

Your household plumbing has a u-shaped pipe included in the set up that is an odor trap component. This pipe is designed to hold water. The water blocks the odors coming from your septic tank so you don’t smell them in the house. If the trap pipe is dry, the odors will come up through your plumbing.

Cold Temperatures

If it’s super cold outside, which we don’t need to worry about right now, your household plumbing vent can freeze over. This will prevent odors from escaping through the vent and push them back into your home. Usually, removing the frozen water from the vent solves the problem and restores the airflow.


If you notice a sewage smell every time we have a downpour here in Greenville, it’s because the excess groundwater and/or ground surface runoff can flood your septic system. If your system is older, it might not have what’s called an intercept drain, which prevents the runoff from heading into the tank.

Tank Vent

Your septic tank has a vent and vent stacks. If the vent stacks get clogged with dirt, leaves, or other debris, you will smell odor backing up inside and out. In some cases, if your septic system was not installed by a professional or you’ve had your home renovated, the tank might not have a vent.

Full Tank

Finally, if your septic tank is full, odors and sewage will back up into your home and possibly outside of the tank underground. To ensure your tank doesn’t get too full, have it inspected yearly and pumped every three to five years. Depending on your household size, it might last longer between pumps or you may need to have it pumped more frequently. It depends on how fast sewage builds up.
Call Express Septic Services today. We are located in Greenville, SC, and we’d be happy to find the source of your septic tank odor. We can also help you maintain your septic system and repair it when necessary. If you need a system, we’re your local area experts so call us today.

Photo by Slphotography from Getty Images via Canva Pro

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