It is not uncommon for homeowners to encounter unusual odors in their household sinks or water. When they do, they want to go to the source of the problem and find out what is causing their water or sinks to have an unpleasant smell.
If you are experiencing a foul odor in your water faucets, you most likely have a problem with the main water supply. On the other hand, if the smell only comes from certain faucets, the problem is probably in the fixtures or pipes involved in those specific faucets.
If your kitchen drain emits a sewer gas smell or smells like sewage, act quickly—these odors are more than just annoying; they could be signs of deeper plumbing issues.
Many homeowners wonder: Why does my kitchen sink smell like sewer, especially when running water? The answer often lies in what’s lurking inside the drain. Suppose you are experiencing a rotten egg (sulfurous) or sewage-like odor in specific sinks. In that case, it is likely a result of bacterial activity, which can be caused by bacterial growth inside the drain pipe. Bacteria are the most common cause of foul odors. As time goes by, hair, soap, and other organic matter accumulate in the walls of the drain, causing a gas that smells like rotten eggs or sewage. How do you tell if the odor is coming from the drain? Fill a glass with water from the sink that smells. Step away from that sink and swirl the water in the glass several times. If the tap water in the glass does not smell, the problem is the smelly drain, not the water supply. This simple test can save time by pointing directly to the drain as the culprit, so you can begin disinfecting or flushing it out.
Some common forms of harmful bacteria found in kitchen sinks include:
Common Causes of Kitchen Sink Odors
Several factors can contribute to a smelly kitchen sink, ranging from blockages and venting issues to microbial buildup in the drain line. These odor-related symptoms often indicate underlying plumbing issues that require prompt investigation. Identifying the specific source of the problem is essential for applying the appropriate corrective measures and preventing recurring odors.Dry P-Trap
If a sink hasn’t been used in a while, the water in the P-trap can evaporate, allowing sewer gases to escape into your kitchen. You can easily fix the trap by running water to refill and block odors.Blocked Vent Pipe
Vent pipes help regulate air pressure in your plumbing. A blockage can trap air, causing sewage smell to build up and emerge from your sink drain.Sewer Gases
When the plumbing system is not adequately sealed, sewer gases can back into your home, resulting in a sink smell like sewage or rotten eggs.Food Debris
Leftover food particles can become lodged in your drain or disposal system, causing a foul odor over time as they decompose.Garbage Disposal Issues
If not properly cleaned, your garbage disposal can collect old food waste, contributing to smelly kitchen sink problems.Biofilm Build-up
A slimy layer of organic waste, known as biofilm, can cling to the walls of your pipes. This material harbors bacteria and contributes to persistent sink drain smell issues. If you’ve identified any of these issues in your kitchen, your next step is determining if the odor is genuinely coming from the drain or something else.Does Your Sink Smell Like Rotten Eggs or Sewage?
Many homeowners wonder: Why does my kitchen sink smell like sewer, especially when running water? The answer often lies in what’s lurking inside the drain. Suppose you are experiencing a rotten egg (sulfurous) or sewage-like odor in specific sinks. In that case, it is likely a result of bacterial activity, which can be caused by bacterial growth inside the drain pipe. Bacteria are the most common cause of foul odors. As time goes by, hair, soap, and other organic matter accumulate in the walls of the drain, causing a gas that smells like rotten eggs or sewage. How do you tell if the odor is coming from the drain? Fill a glass with water from the sink that smells. Step away from that sink and swirl the water in the glass several times. If the tap water in the glass does not smell, the problem is the smelly drain, not the water supply. This simple test can save time by pointing directly to the drain as the culprit, so you can begin disinfecting or flushing it out.
Another Cause of Odors: Water Heaters
Sometimes, the problem isn’t in your sink at all. Plumbing systems and water heaters can also source sewer smells in your kitchen. When organic matter is trapped in the plumbing, it can release sulfur or sewage-like odors that interact with the chlorine in the water. When you run your hot water, these bacteria and enzymes can cause that rotten egg smell. While foul odors can come from the drain, they can also originate from water heaters that have not been used in a while. If you’ve recently moved into a home with a seldom-used water heater, flushing the tank can eliminate lingering bacteria and enzymes that produce that sewer-like smell. Inspect all parts of your plumbing system, not just the visible ones, when tracking down a persistent odor.Three Bacteria Your Sink May Be Hosting
Kitchen sinks are notorious breeding grounds for bacteria. If you have a stinky sink, bacteria may be to blame. Your shiny new kitchen sink provides luxury living quarters for a variety of microorganisms harmful to human health. High moisture levels and food residue common to areas around kitchen sinks create ideal environments for bacterial growth. It’s estimated that kitchen sinks harbor more bacteria than bathroom sinks.
Some common forms of harmful bacteria found in kitchen sinks include:
- Salmonella – Kitchen sinks regularly exposed to fresh produce, raw meat, eggs, or dairy products have an elevated risk of carrying salmonella bacteria, which can cause dangerous gastrointestinal illnesses.
- E. coli – Sinks can carry E. coli bacteria, which can also cause serious gastrointestinal illnesses, some of which can be fatal.
- Staph – Staph thrives in moist conditions, and the area around a kitchen sink is optimal for their Staph can cause many illnesses, including wound infections, toxic shock, pneumonia, and food poisoning.
Garbage Disposals Can Cause a Smelly Sink
A smelly kitchen sink may also result from a dirty or clogged garbage disposal. Trapped food particles in the disposal decay over time, contributing to foul odors and a persistent sewage smell. Like a p-trap with gunk buildup, a dirty garbage disposal can cause unpleasant odors. Simple at-home cleaning solutions can help. Using baking soda and a cup of vinegar, or boiling water and dish soap, white vinegar, citrus peels, or other drain cleaners can help ensure that the garbage disposal and any blockages from a buildup of food particles that are causing the kitchen sink smells are all taken care of before it gets too far. Ice cubes with coarse salt can also clean disposal blades, although this method isn’t always effective. The ice cubes usually melt before they can completely clean the garbage disposal. DIY maintenance of your garbage disposal eliminates bad smells and prevents larger plumbing issues requiring a professional plumber.Plumbing Vents May Also Cause Unpleasant Odors From The Kitchen Sink
Ventilation issues in your plumbing can also lead to unexpected odors in your kitchen sink. Your home’s plumbing system is built around having a drain vent, or plumbing vent. A blocked or damaged vent pipe prevents proper air circulation, allowing sewer gases to back up into the kitchen. The pressure can push sewer odors through traps and vents if the pressure isn’t balanced. This issue often affects the entire drain line and is best resolved by a professional. If you suspect a vent problem and your sink smells like sewer despite cleaning, it’s time to investigate deeper into your home’s plumbing system. When you have issues with a clogged vent, a broken garbage disposal, or kitchen sink smells that you cannot get rid of, call A-1 Sewer & Septic Service.How to Prevent Kitchen Sink Odors
Prevention is the best cure for keeping your kitchen sink smelling fresh. Homeowners can significantly reduce the risk of sewer gases, bacterial buildup, and other odor-causing plumbing issues by following a few proactive maintenance steps. Routine cleaning and proper disposal habits help maintain a sanitary and odor-free kitchen environment.- Place a drain screen or sink strainer over the plughole
- Avoid pouring fats, oils, and grease down kitchen drains
- Avoid putting food down the drain
- Prevent smells caused by P-trap dryness by running water in all the sinks in your home at least once a week.
- Pour boiling water down the drains weekly to kill bacteria
- Use baking soda and vinegar weekly for routine cleaning of kitchen sink drains
- Schedule regular maintenance, checks, and clean-out services with a professional plumbing and drainage service