Symptoms
- Foul or rotten smell near the sink
- Smell worsens after running hot water
- Odor noticeable even with no visible mess
- Smell returns a few days after cleaning
Likely causes
- CommonFood residue trapped under the rubber splash guardThe baffle flaps trap scraps that rot out of sight.
- CommonGrease buildup coating the grind chamberGrease clings to walls and holds odor-causing bacteria.
- PossibleStanding water in the trap with old debrisA partially clogged trap can hold rotting particles.
- Less commonDry P-trap allowing sewer gas smellIf the sink is rarely used, the trap can dry out and let sewer odor through.
What to do
- Turn off and unplug the disposal before reaching near the blades.
- Lift the rubber splash guard flaps and scrub underneath with an old toothbrush and dish soap.
- Grind a handful of ice cubes with cold water running to knock grease and residue off the chamber walls.
- Grind a few citrus peels (lemon or orange) to freshen the smell naturally.
- Pour a half cup of baking soda followed by a half cup of vinegar down the drain, let it fizz for 10 minutes, then flush with hot water.
- If the smell persists, check the trap for debris as described in the slow-draining guide.
- Run the disposal regularly with water to prevent residue from building back up.
Tools and parts
- Old toothbrush or scrub brush
- Ice cubes
- Baking soda
- Vinegar
- Citrus peels
When to call a pro
If odor smells like sewage rather than rotten food and persists after cleaning, a plumber should check the trap and venting.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.