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Why Does My Bathroom Sink Smell

You might be wondering, “Why does my bathroom sink smell?” The truth is, there can be many things causing your bathroom sink to smell like a sewer. Today, we’re here to help you figure out which of those things is causing the odor so you can get back to having a fresh-smelling home.

Three of the most common reasons include: 

  • The sink has a build-up of bacteria formulating in it. 
  • Ventilation problems. 
  • Problems with sewer lines.
  • No water in the p trap. 

Let’s explore why your bathroom might smell awful, and then we will try and learn how to fix it. 

 

Accumulation of Bacteria

Some nasty things go down the bathroom sink daily when you think about it. Soapy water, toothpaste, dead skin cells, and shaving cream are the most common items. 

Eventually, these items make their way down the drain and into the pipes below. These pipes are an ideal place for bacterial growth. After a while, the bacteria growth turns into black, nasty gunk, often referred to as biofilm. The odor you are now smelling is the result of this biofilm. 

 

Issues with the Sewer Lines

The reason you are smelling an odor that is similar to sewage is because that is what it is. Your home’s plumbing system is an intricate labyrinth of pipes that go from the drains straight to the sewer. 

Those odors you are smelling might indicate a more complex issue with the entire plumbing system. Encompassing the sewer gas that is coming up from the pipes and through the drain. 

Remember this, all that waste sent through the pipes ends up in the sewer. Therefore, if you are smelling sewer odors in your bathroom, there could be a ventilation issue or the p-traps.

 

Ventilation Problems

Sometimes the scent of escaping sewer gas comes up through the drains in a bathroom. When this happens, it is a sure indication of an issue with the plumbing’s ventilation system. It can also mean there is some sort of clog in the drains. 

 

The P Trap is Dry

Another alternate issue may be the p-trap is dry. You might be wondering what the p-trap is. It is a curved portion of piping under a sink. Its primary job is to provide a water barricade, guarding against gas seepage from the sewer into the bathroom. The p-trap is also made as a curved portion of the pipe to prevent objects from getting into septic tanks or the sewer line.

However, should this unique pipe segment become dry, that protective water barrier no longer exists. With a dried up p-trap all those sewer gases escape into the sink drains, and enter your bathroom via the pipes.

Besides making your bathroom stink, it is also extremely unsanitary. It’s a normal process for the p-trap to dry out over time; however, it’s really simple to fix. 

Related: Septic Smells in the House? Here’s How to Get Rid of Septic Smells

 

How to Remove that Rotten Smell from a Bathroom Sink

We have uncovered the common reasons why your bathroom sink smells like sewer. This section will help you with some ideas or possible answers to fixing the issue. Simply pouring vinegar into the bathroom drains might be the solution.

You can also use a mixture of baking soda and vinegar poured into the bathroom drains. You can also use scented candles and potpourri to effectively remove bad smells.

 

Get rid of the Biofilm Build-up

Biofilm is that nasty gunk on the bottom of a sink stopper,also a possible cause for sink odors. It would be best if you got rid of the build-up of bacteria, which is the reason for the bad smell. 

The first step to cleaning and ridding your bathroom of biofilm build-up is the right cleaning supplies. There are many products you can purchase for cleaning at the store level. However, there are also household products you will find in your pantry, such as distilled white vinegar (never combine bleach with vinegar). This will create a chemical that is noxious, and the fumes can be harmful.

 

Flush out the bacteria

To flush and break down any bacteria, it is advisable to pour hot water down the drain first. Or, you can turn on the hot water tap and let it run for a short time. 

In some instances, this won’t be sufficient to get rid of the smell (or bacteria) because of severe build-up. If this is the case, you will need to turn off the main water source, and disconnect the sinks plumbing beneath it. Then you can clean out each pipe individually. Rinsing each one with an outdoor hose or faucet and wiping clean with a paper towel. Just remember how you took the pipes apart, so you can reassemble them when you are done cleaning.

 

Putting Water into the P-Trap

As mentioned above, that awful rotten egg smell could be due to the p-trap having dried out and sewer gases seeping up the drain. If this is the case, you need to add some water to it, which may be simpler than you think. You can run the tap water for a couple minutes. This will permit the p trap’s guarding barrier of moisture to be restored. 

However, you might need to call in a professional plumber if this doesn’t work. You may have misdiagnosed the issue and it is something far more complex.

 

Repair the Ventilation

If it is the ventilation system that has gone bad that is permitting sewer gases to escape, there may be a more complex fix. In this case, in order to stop these nasty gases and fumes from stinking up your home, you need a professional plumber’s assistance. 

 

More ways to clean a sink drain

Sometimes a smelly sink is the result of an overflow pipe that has become clogged. If this is the case, you can clean it with a simple solution found in your kitchen pantry. 

With a few household items– distilled white vinegar and baking soda– you can concoct a powerful cleaning compound. This combination can be poured directly down the drain and will dissolve gunk, eliminating odors almost instantaneously! 

Another option, less toxic, is some bleach with oxygen added.  You can clean the overflow of your bathroom sink with this bleach. If you are not sure where the overflow drain is, it is a small hole found at the sink’s top. 

You can also make a mixture of one cup distilled white vinegar and one cup baking soda to clean your overflow sink drain. Just follow these simple steps: 

 

  • Stir the soda and vinegar together, so it is completely blended. 
  • Close the sink’s filter.
  • Pour the concoction down the overflow hole in the sink.
  • Allow it to sit for about five to ten minutes. 
  • Boil some water in a pot while you are allowing this to set. 
  • After you have waited for the appropriate time, pour the hot water down this small hole to flush everything out. 
  •  

This is a safe, non-toxic method to clean the debris and build-up of bacteria from your sink drain and get rid of sewer smell.

 

How to Get Rid of that Sewer Smell in your Drain 

You can get rid of that sewer smell in your sink drain by pouring hot, boiling water down it. Wait about five minutes, and then pour down the same amount of cold water. Anything that was blocking and creating the smell should be dissolved after doing this. 

 

A plunger can help

To clear out a smelly drain you can enlist the assistance of a plunger. Just put the plunger’s cup on top of the sink drain and vigorously pump it for a few minutes. This should get rid of any small clogs or blockages. 

After you have done this, you can flush it once more with boiling water. This should be enough to get rid of anything that has congealed and clogged your sink drain.

 

Problems of a Plumbing System

The plumbing in a person’s home is something most don’t think about until something out of the ordinary occurs. Such as a clogged drain or the foul odor of smelly drains. 

 

Why Your Drain Smells of Sewer Gases

There are many reasons for smelly drains, from a clogged pipeline or drain. When something solid gets clogged in the pipeline, it keeps water from flowing freely. Therefore, making everything go stagnant. 

 

How do you get rid of that sewer smell?

If you are wondering how to get rid of that sewage smell in your home we have some simple tips. A simple mixture of baking soda and vinegar will work to get rid of most unpleasant odors.

There are also several reasons why your bathtub drain or shower drain has a foul odor. If your drain smells it may be that you have a dry p trap. A smelly drain can also indicate a blockage in the sewer system.

Another reason for a smelly drain is a clog in the drain system. When food particles get trapped in the garbage disposal it can cause the kitchen sink to emit a foul smell coming out of the drain system.

 

How do Foul Odors Develop?

With all drains there is a inside area that has the potential for breeding bad odors. This is also true of kitchen drains and shower drains. What is causing that awful drain smell? Most likely there is some form of bacteria that is eating the debris left behind from soap scum and other material. This drain smell can be similar to the unpleasant smell of rotten eggs, with is what raw sewage is often described as.

 

You Might Need a Plumber

Sometimes when you are troubleshooting smelly drains, you might need to call a plumber to find the answer. If the vent pipe has been damaged or cracked, this will need repairing. Only a professional plumber knows how to determine the cause for a drain smell and smelly drains.

If you have a garbage disposal, the drain smell might be coming from trapped food particles in the drain. You can fix this by pouring boiling water down the sink drains.

 

How to Get Rid of the Smell of Sewer Gasses in my Sink

If you have a guest bathroom, the stinky smell might be coming from there. Perhaps the p-trap has dried out due to lack of use. Or the main drain has mold growth accumulating in it.

 

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