07/22/2026
Wastewater Wednesday! Answer:
That unpleasant sewer smell in your home is usually caused by sewer gases escaping from your plumbing system. Your home's plumbing is designed with barriers, called traps, that hold water to prevent these gases from entering your living space.
Common sources of sewer odors include:
đźš° Dry drain traps
If a sink, shower, floor drain, or other plumbing fixture isn't used often, the water in the trap can evaporate and allow sewer gases to enter your home. Pouring a small amount of water down unused drains can help refill the trap.
🛠️ Plumbing leaks or damaged seals
Cracked pipes, loose connections, or worn seals can allow odors to escape.
🌬️ Blocked plumbing vents
Vent pipes allow sewer gases to safely escape through your roof. If a vent becomes blocked, gases may be pushed back into your home through drains.
đźš˝ Toilet issues
A damaged wax ring or loose toilet connection can allow odors to escape around the base of the toilet.
đź§Ľ Buildup in drains
Organic material, soap scum, grease, and debris can collect in drains and create unpleasant smells.
Where do sewer odors come from?
Sewer gases come from the natural breakdown of wastewater inside your plumbing and sewer system. These gases are normally contained within the pipes and safely released through vent systems. When something disrupts that system, you may notice the smell inside your home.
A helpful tip: If you notice a persistent sewer odor, try to identify where it is strongest—near a sink, toilet, shower, or floor drain. Locating the source can help determine the cause.
A properly working sewer system should operate quietly and odor-free.