When your bathroom has an odd odor, it might take a little while to track down the problem. If it seems to be coming from the sink, you may need the help of trusted local plumbers to answer the question: Why does my bathroom sink drain smell? Several situations can cause this unpleasant situation, some of which need immediate repair or cleaning.
Learn what you should do when certain issues cause a foul odor in a bathroom sink.
Sewer Gases Are Escaping From the Drain
Although your plumbing system has a couple of design elements made to prevent sewer gas from escaping into your house, these elements could fail. If so, you may notice odd odors in the drains.
The P-Trap Isn’t Retaining Water
Some people notice odd odors in guest bathrooms that don’t have frequent use, sparking the question: Why does my bathroom sink drain smell? The P-trap’s design is specifically made to block sewer gases by retaining water in the curved section of the pipe. However, in a bathroom that doesn’t see much use, the water in the P-trap may evaporate, giving sewer gases a path to float out of the drain.
Running water in the sink every couple of weeks should keep the P-trap full.
The Vent Pipe Has a Blockage
A vent pipe blockage can create poor odors in drains. The vent pipe connects to your sewer pipe and extends vertically through the roof or an upper wall of the house. This pipe allows air and gas inside the sewer line to float away instead of remaining trapped in the sewer system.
Birds might build a nest over the top of the vent, preventing gas from escaping. Depending on the location of the vent pipe, piles of old leaves or branches could block the opening. Plumbers can inspect the vent and remove the blockage to return everything to normal operation.
Sticky Substances Are Building Up in the Drain Pipe
A clogged drain can encourage bacteria buildup that creates odors. Even small clogs in the drain create an opportunity for toothpaste, soap scum, and shaved hair to cling to the clog. Eventually, the moist environment in the drain allows bacteria to grow.
As the bacteria feed on organic matter stuck near the clog, they create microorganisms that exist in a slimy, black layer, called biofilm. The odors in the biofilm can smell like raw sewage or rotten eggs.
Sometimes, the biofilm might be on a bathtub drain stopper or sink stopper, which generates the unwanted odor. Shining a flashlight into the drain might reveal the black, slimy substance near the edges.
You can try cleaning the stoppers and interior of the drain with a disinfecting spray. Otherwise, you may need a plumber to completely clean the drain.
Your Sewer Pipe Has a Blockage
“If my drains are clear,” you might wonder, “why does my bathroom sink drain smell?” A pipe blockage farther down the sewer line could be the source of the odor.
If you have a bathroom sink in the basement of your home, a blockage in the sewer line could create odors in the basement sink. Any sewer gases trapped by the blockage would likely escape from the closest drain, which could be in a basement bathroom.
You may need to hire a plumber to inspect the sewer line and determine whether it needs clearing with a plumbing snake.
The Odor Might Come From the Water Source
Some odors in the sink might not originate from the drain at all. If your water supply has contamination from bacteria or organic material, it may generate an unpleasant odor as you run it from the faucets. You might also have odor-causing contaminants trapped inside the sink’s fixture.
A plumber can investigate this issue and make recommendations on how to treat the water or clean the fixture.
Let Our Expert Plumbers Quickly Track Down the Source of an Odd Sink Odor
Don’t put up with strange odors from your drain. Although some DIY drain-cleaning remedies might briefly alleviate the odor, not every method is safe and effective. In fact, drain cleaners and other store-bought products often contain harsh chemicals that are ultimately bad for your pipes. Let the professionals permanently fix the issue.
Whether you want emergency drain cleaning because the odor is overwhelming or you want to set up a regular appointment time, we can help. Call Expert Plumbing & Water Heaters, Inc. today at (831) 713-1529. We will respond on time and provide the highest level of customer service.
