How to Clean a Stinky Drain
Troubleshooting and Deodorizing Bathroom and Kitchen Drains
You've just spent several hours cleaning every surface in your kitchen and bathroom to a sparkling clean shine. But as you look around at your handiwork, you catch a whiff of something smelly. Did you forget to clean the drains?
Even with all of the water and cleaners that pass through a kitchen or bathroom drain, they can still reek. There are several possible causes of stinky drains:
- A dry P-trap: The P-trap is the curved portion of the pipes under a sink. It is designed to hold water to create a seal between the odors and gasses of sewage lines and the sink drain.
- A clogged or blocked air vent: In bathrooms, the drains are vented to give backflowing gases a release outlet.
- A clogged pipe or garbage disposal: An obstruction traps foul-smelling waste in the drain.
- Odor-causing bacteria: Bacteria can build up in drains and feed on debris if the pipes are not flushed regularly. The bacteria give off hydrogen sulfide gas that smells like rotten eggs.
- Mold: Drains are dark, warm, wet, and filled with food for mold, and some mold colonies emit a foul odor.
- Clogged aerator: At the end of the faucet is a small screen or aerator that catches debris from your water source that can cause odors.
Once you have determined the possible cause of the odor, it's time to solve the problem and clean the drain. Some odors can be removed with a simple cleaning process; others require a plumber or your plumbing skills to remove an obstruction.
How Often to Clean a Stinky Drain
A stinky drain should be cleaned as quickly as possible. Even drains that don't smell require regular attention monthly.
What You'll Need
Equipment / Tools
- Rubber gloves
- Measuring cup
- Garden hose (optional)
- Microwave or stovetop
- Old toothbrush
- Pot or microwavable bowl
- Distilled white vinegar
- Baking soda
Instructions to Clean a Stinky Drain
Getting rid of the stinky odor is often a process of elimination. Start by flushing the drain with distilled white vinegar and baking soda and see if that removes the odor. If not, progress to the next steps until all of the odor is gone.
Flush the Drain
- In a large measuring cup or bowl, combine one cup of distilled white vinegar and one cup of boiling water. Pour one-half cup of baking soda down the drain followed by the vinegar and hot water mixture.
- Cover the sink drain with the drain plug and allow the mixture to work for 10 minutes. There may be some foaming as the baking soda and vinegar react with each other.
- After 10 minutes, flush the drain with an additional two cups of very hot water. This will remove debris and fill the P-trap with clean water to eliminate odors.
Clean the Kitchen Sink Garbage Disposal
- Kitchen sink odor may be coming from a garbage disposal unit. Before you begin the cleaning steps, turn off the electrical breaker for the disposal to prevent injuries.
- Use a paste of baking soda and a few drops of water on a sponge to clean the rubber baffle of the disposal near the sink drain opening. Be sure to clean the underside of the baffle.
- Follow the steps for flushing a drain with vinegar, baking soda, and hot water. If you have a double sink, cover the opening of the sink drain in both sinks.
Clean the Faucet or Showerhead Aerator
Unscrew the end of the faucet and use an old toothbrush and a bit of damp baking soda to clean away any debris or mold that may be on the aerator screen. Remove the showerhead and submerge it in a bowl of warm distilled white vinegar. Let it soak for 30 minutes. Use an old toothbrush to remove any visible mold or debris from the nozzles, rinse, and reinstall the showerhead.
Clean the P-Trap
- Remove all items from underneath the sink and place a bucket under the curved portion of the drainage pipe to catch water and debris.
- Use a wrench to loosen and remove the P-trap.
- Wearing rubber gloves, empty any water and debris from the trap into the bucket. You can take the P-trap outside to rinse it out with a garden hose or flush it with water from another sink into the bucket.
- Reassemble the drainage system.
- Flush the sink with distilled vinegar, baking soda, and hot water as directed in the first step.
Remove Air Vent Blockages
If you feel the drain air vent may be blocked, use a sturdy ladder and climb to the roof to remove leaves or debris that may be clogging the vent.
Always work with an assistant when working on a roof. Never climb alone, make sure your ladder is sturdy, and have your assistant steady the base for you. If in doubt, hire a professional to check out your roof.
How to Prevent Stinky Drains After Cleaning
Cleaning out your drains doesn't prevent odors from returning. Here are tips to maintain a fresh drain or to somewhat prevent a stinky drain from recurring after you clean it.
- Once a week, pour a large pot of boiling water down kitchen and bath drains.
- Sprinkle baking soda down all of your sink and shower drains every week to absorb odors.
- If you have a kitchen garbage disposal, run it for 20 seconds every time food goes down the drain.
- To minimize smells in your shower drain, plunge it every so often and then snake it with a hair catcher.
When to Call a Professional
If none of these methods work (or you feel uncertain about completing them), consider calling an expert. There may be a leak in the plumbing lines or a sewage line problem that will require a professional plumber.
Can you pour bleach down a smelly drain?
Yes. If the drain is not clogged but is simply smelly, try pouring a cup of liquid chlorine bleach down the drain and follow it with a stream of very hot water for about a minute or two. This action can sanitize but not unclog a drain because it cannot eat through hair, soap scum, and other gunk causing the blockage.
How do you unclog and deodorize a drain?
If you want to effectively unclog and deodorize a drain naturally, you will need a few more products. If there is a small amount of water, this is your best bet. If there's too much standing water, this method may not work well. Pour a pot of boiling water and a few drops of dish soap (to dissolve grease) into the clogged drain. Then pour a cup of baking soda in and immediately follow with a cup of white vinegar. There will be a fizzing reaction that can hopefully dislodge the clog. Flush with more very hot water and repeat if necessary.
Can a plumber fix a smelly drain?
A plumber has the tools and knowledge to pinpoint where the nasty smell is coming from, whether it's due to bacteria, gunk, sewer gases, or blocked plumbing vents.