How to Clean a Stinky Drain

Clogged sink drain with dirty water and herbs floating

The Spruce / Almar Creative

Project Overview
  • Working Time: 10 mins - 1 hr
  • Total Time: 15 mins - 1 hr
  • Skill Level: Beginner

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 stinky. 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 drain odor:

  • 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
  • Wrench
  • Bucket
  • Garden hose (optional)
  • Microwave or stovetop
  • Old toothbrush
  • Ladder
  • Sponge
  • Pot or microwavable bowl

Materials

  • Distilled white vinegar
  • Baking soda

Instructions

Materials and tools to clean a stinky drain

The Spruce / Almar Creative

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.

  1. Flush the Drain

    1. 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.
    2. 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.
    3. 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.
    Cup of baking soda poured down stinky kitchen drain

    The Spruce / Almar Creative

  2. Clean the Kitchen Sink Garbage Disposal

    1. 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.
    2. 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.
    3. 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.

    Tip

    If the smell persists, grind up sliced or halved lemons in the garbage disposal: This can also help remove any odor.

    Sponge with baking soda paste cleaning kitchen sink garbage disposal

    The Spruce / Almar Creative

  3. 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.

    Kitchen faucet cleaned with old toothbrush and baking soda

    The Spruce / Almar Creative

  4. Clean the P-Trap

    1. Remove all items from underneath the sink and place a bucket under the curved portion of the drainage pipe to catch water and debris.
    2. Use a wrench to loosen and remove the P-trap.
    3. 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.
    4. Reassemble the drainage system.
    5. Flush the sink with distilled vinegar, baking soda, and hot water as directed in the first step.
    P-trap loosened with wrench under kitchen sink

    The Spruce / Almar Creative

  5. 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.

    Warning

    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.

    Air vent being checked on roof

    The Spruce / Almar Creative

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.