Sewage smells from your garbage disposal typically indicate trapped food debris decomposing in the grinding chamber, splash guard, or a dry P-trap that's allowing sewer gases to escape. Fix it by grinding ice cubes with rock salt to dislodge buildup, thoroughly cleaning under the rubber splash guard with a brush and dish soap, and running cold water for 30 seconds after each use. If odors persist after cleaning, the P-trap may have a leak or your disposal could have failing seals that need professional replacement.
Common Causes of Sewage Odors in Garbage Disposals
That unpleasant sewage smell coming from your garbage disposal can quickly make your kitchen an uncomfortable place to be. Understanding what's causing these odors is the first step to eliminating them. As Denver's trusted plumbing experts, we've identified several common culprits behind disposal odors:
Trapped Food Debris
The most common cause of disposal odors is food particles that become trapped in various parts of the unit. Over time, these particles decompose, creating that unmistakable rotten smell. Areas where debris often hides include:
- The grinding chamber itself
- Under the rubber splash guard or baffle
- In crevices around the disposal unit
- In the drain line immediately below the disposal
Unlike regular sink drains that only handle water, disposals process food waste, creating more opportunity for odor-causing buildups. Certain foods like fish, eggs, and dairy products are particularly prone to causing strong odors as they break down.
Dry P-Trap
Another potential source of sewage smells is a dry P-trap. The P-trap is the curved section of pipe beneath your sink that retains water, creating a seal that prevents sewer gases from entering your home. If your disposal isn't used frequently or you've been away from home, this water seal can evaporate, allowing sewer gases to rise through the drain.
Failing Disposal Seals
In older garbage disposals, the internal seals can deteriorate over time. These seals are designed to prevent water and waste from leaking out of the unit, but they also help block sewer gases. When these seals fail, unpleasant odors from your plumbing system can escape through the disposal.
How to Eliminate Garbage Disposal Odors
The good news is that most disposal odor issues can be resolved with proper cleaning and maintenance. Here's how to tackle the problem effectively:
Deep Clean the Grinding Chamber
- Ice and Salt Method: Fill the disposal with ice cubes and a cup of rock salt. Run cold water and turn on the disposal. The ice helps scrape away buildup while the salt acts as an abrasive cleaner.
- Citrus Refresh: After cleaning with ice, grind citrus peels (lemon or orange work well) with cold water to help neutralize odors and leave a fresh scent.
- Baking Soda and Vinegar: Pour half a cup of baking soda into the disposal followed by a cup of white vinegar. Let it fizz for a few minutes, then flush with hot water.
Clean the Splash Guard
The rubber splash guard (the flappy piece at the drain opening) is often the main culprit for harboring smelly bacteria:
- Turn off power to the disposal at the circuit breaker for safety
- Use a toothbrush or dish brush with dish soap to scrub under and around all the rubber flaps
- Pay special attention to the underside of the splash guard where slime often accumulates
- Rinse thoroughly with hot water
Proper Disposal Usage Habits
Prevent future odors by following these best practices:
- Always run cold water before, during, and for 30 seconds after using the disposal
- Avoid putting fibrous or starchy foods (potato peels, celery, coffee grounds) in the disposal
- Cut larger items into smaller pieces before grinding
- Run the disposal regularly, even if just with water, to prevent the P-trap from drying out
Address Plumbing Issues
If odors persist after thorough cleaning:
- Check for leaks in the P-trap beneath the disposal
- Run water in rarely-used sinks to refill P-traps
- Consider having a professional inspect for failing seals or other plumbing issues
When to Call a Professional Plumber
While many disposal odor issues can be resolved with DIY methods, sometimes you need professional assistance. Contact Bedrock Plumbing & Drain Cleaning if:
- Sewage smells persist after multiple cleaning attempts
- You notice leaks beneath your disposal
- Your disposal is more than 10 years old and may have failing internal components
- The disposal makes unusual noises or doesn't function properly
Our experienced Denver plumbers can diagnose complex issues and determine if a repair or replacement is needed. We can also inspect your overall plumbing system to ensure there aren't larger sewer line problems contributing to the odors.
Preventative Maintenance Tips
Keep your disposal odor-free with these ongoing maintenance tips:
- Weekly cleaning with ice and salt or baking soda and vinegar
- Monthly deep cleaning of the splash guard
- Using cold water generously when operating the disposal
- Grinding citrus peels occasionally for a fresh scent
Don't let a smelly garbage disposal ruin your kitchen experience. For persistent issues or professional maintenance, contact Bedrock Plumbing & Drain Cleaning today. Our Denver plumbing experts are ready to help ensure your disposal runs clean and odor-free.