Ask Pete – Why Does My Drain Smell Bad

Hello, homeowners of Gilbert and Mesa, Arizona! As your trusted local plumber, we understand that dealing with nasty smells in your home can be a nightmare. One common issue we often encounter is foul odors coming straight from drains. Don’t worry; you’re not alone in this! In this blog, we’ll explore the possible reasons behind those unpleasant drain smells and guide you on how to eliminate them effectively.

Clogged or Dirty Drains

  • One of the most common reasons for bad smells coming from drains is clogs or accumulated dirt and debris in the pipes. Over time, organic matter can build up in the drain, leading to foul odors.
  • Cause: Food particles, grease, hair, and soap scum can get trapped in the pipes, creating a breeding ground for bacteria that produce the bad smell.
  • Solution: Regularly clean your drains using a mixture of baking soda and vinegar. This natural solution can help break down the debris and keep your drains fresh.

The Dried-Out Drainage Dilemma 

The P-trap is a curved section of the drainpipe that holds water, preventing sewer gasses from entering your home. If the P-trap dries out, it can allow foul-smelling gas to waft up from the sewer system.

  • Cause: Infrequently used sinks, showers, or floor drains can cause the water in the P-trap to evaporate, leaving it dry and ineffective.
  • Solution: Run water through all your drains regularly to keep the P-trap filled, preventing unwanted odors from entering your home.

Sewer Line Issues: Serious Smell Source

If multiple drains in your home emit foul odors, it could be a sign of sewer line problems. Damaged or clogged sewer lines can lead to strong, unpleasant smells.

  • Cause: Tree roots, debris, or deteriorating sewer pipes can cause blockages or leaks in the sewer line, allowing sewer gasses to escape.
  • Solution: If you suspect sewer line issues, contact a professional plumber immediately. They can inspect the sewer line, identify the problem, and perform necessary repairs.

Garbage Disposal Troubles: 

A smelly garbage disposal can contribute to bad odors in your kitchen sink. Here’s what typically causes the issue and how to fix it.

  • Cause: Food debris and buildup can get stuck in the garbage disposal, leading to a foul smell.
  • Solution: Regularly clean your garbage disposal by grinding ice cubes and citrus peels to remove the debris and freshen up the disposal.

Improper Ventilation

Inadequate ventilation in your drainage system can trap foul-smelling gasses, causing odors to linger in your home.

  • Cause: Blocked or poorly designed vents can hinder proper air circulation, leading to trapped odors in the pipes.
  • Solution: Consult a professional plumber to inspect and clear any vent blockages to ensure proper ventilation and eliminate bad smells.


Don’t let bad smells from drains spoil the atmosphere in your home. Understanding the root causes of these odors is the key to effectively eliminating them. From clogged drains to dry P-traps and sewer line issues, each problem has its solution. If you’re facing persistent or complex drain smell issues, don’t hesitate to reach out to your local plumbing experts at 480-388-6093. We’re here to help ensure your home is free from unwanted odors, and your plumbing system is in optimal condition. Let’s keep your home smelling fresh and welcoming!