Sewer Odor Guide

Sewer odor issues are unpleasant and inconvenient, and identifying the underlying issue causing them can be challenging.  We hope this guide will help in identifying and resolving sewer odor issues.

Inside the Home

There are several places within a home that can become a source of odors. 

1) Biofilm Accumulation in drains:

This is most commonly found in tub or shower drains. When we shower, we use many different products. Body oils, conditioner, shampoo, soap and shaving cream wash down the drain along with natural debris like skin cells and hair. Regular cleaning can help alleviate the residue of some of this, but eventually, it can start to build up and create issues like clogs, slow drainage and fumes. Over time, these substances often accumulate along the P-trap and vertical pipes that run underneath your shower/tub.  As it builds up, biofilm begins to release a sewage smell from bacteria and decomposing debris. The bacteria emit a sticky substance that allows them to cling to the side of your pipes, making them difficult to remove without specialized products.

Fixing this problem is an easy process that does not require a plumber.  Simply remove any accumulated debris that is feed the bacteria in the drain.  Over the counter solutions to dissolve drain build-up can be found at your local hardware store.

2) Dry P-traps:

The P-trap is a U-shaped pipe designed to trap and hold water.  When working correctly, a P-trap is supposed to hold enough water to prevent gases and odors from the sewer to creep up your drain.  If you do not use a sink, shower or tub frequently, the water in the trap can evaporate and allow sewer gas to enter the home.  Simply run water into the drain for a couple of minutes.

If running water into the drains does not solve the odor issue, you may be dealing with an old or leaky P-trap.  For best results, contact a plumbing professional to examine your P-traps.

3) Improperly installed or damaged vent pipe:

Vent pipes help in regulating the air pressure in your home’s plumbing system.  They are placed within the walls of the home, and run up through the roof.  This allows them to redirect any odors to the outside.  Damage to these can occur during installation, through age, or when a puncture is made in the wall that also hits the pipe.  If you suspect a damaged pipe vent, contact a plumbing professional for assistance.

4) Broken or loose toilet seal:

If your toilet is emitting a strong sewage smell, it could have a broken or loose seal.  A wobbly or loose toilet will prevent the wax ring from working correctly.  This could allow gas, and water to leak from the base of the toilet when it is flushed.  Tighten the bolts at the base of the toilet, exercising care not to over-tighten, to see if the odors stop.  If not, you may need to contact

Outside the home

1) Manholes or Lift Stations:

If you experience a persistent odor coming from a manhole or lift station, please contact us at 1-800-248-7689 so we may investigate further.