A sewage smell in your dishwasher is usually caused by trapped food rotting in the filter, stagnant dirty water, or a plumbing issue allowing sewer gases to back up into the machine. It rarely means there is an actual sewer line break, but rather a drainage or buildup problem.
Here are some household cleaning steps that can help eliminate the sewage odor from your dishwasher.
A washing machine drain that smells like rotten eggs is typically caused by a dry P-trap allowing sewer gas to escape, bacterial buildup from soap scum and lint in the drain hose, or a clogged drain filter.
Baking soda and vinegar
Follow with two cups of vinegar. Listen for bubbling and sizzling noises to indicate that the mixture is working. Wait another couple of minutes before either flushing the toilet or running water down the drain. If you still notice a smell, repeat the steps again.
To quickly eliminate that stubborn, sulfur-like egg smell, manually scrub the filter and spray arms to remove trapped food, then run an empty, hot cycle with a bowl of white vinegar.
The vinegar and added baking soda cycles can pay dividends in removing remaining residue left in the dishwasher by food waste. Baking soda's property as a deodorizer may also be beneficial if your dishwasher has been giving off an unwelcome musty stench.
The average lifespan of a dishwasher is 9 to 12 years. However, premium brands properly maintained can last up to 15 years, while heavy use or hard water can cause models to break down in 7 to 8 years.
Eliminating a sewer smell in your home typically comes down to sealing dry plumbing traps, clearing clogged vents, or fixing broken seals. Start with these quick fixes:
The characteristic "old age smell" is scientifically known as nonenal (or 2-nonenal). It is a chemical compound produced when the skin's natural oils and fatty acids break down and oxidize as we age.
The hardest smells to eliminate from a house are cigarette smoke, pet urine, and skunk spray. These odors penetrate deep into porous materials (drywall, subfloors, carpets, and air vents), often requiring professional remediation rather than standard cleaning.
The first signs of sewer gas exposure are a distinct rotten egg odor and physical irritation. Prolonged or stronger exposure commonly leads to the following early symptoms:
Plumbers recommend resolving smelly drains by first identifying the source. Most odors are caused by bacteria buildup from hair, grease, and soap scum, or a dry P-trap letting sewer gases escape. The most common remedies include routine enzyme treatments, vinegar and baking soda flushes, and physically scrubbing the pipe.
Hot Water Supply
The bacteria in the water heater are not a health threat; however, they must be eliminated to stop the odor problem. You should consult your owner's manual or contact a licensed plumber.
If your machine is still slow to drain, pour vinegar and baking soda into the basket at the bottom of the dishwasher. After 15 minutes, flush with hot water.
Drano can work well if your drain smells bad due to minor clogs. If food, grease, or soap buildup is causing slow drainage and mild odors, it may clear things up. However, if the issue is sewer-related or due to bacteria, it won't be much help.
To quickly deodorize your dishwasher, place a dishwasher-safe bowl filled with 1 cup of white vinegar on the top rack of an empty machine and run a hot water cycle. Follow it by sprinkling a cup of baking soda across the bottom and running a short, hot rinse cycle.
"Old person smell" can begin as early as age 40, as the body produces more of the compound 2-nonenal. This, often described as a grassy, greasy, or musty odor, is a natural part of aging caused by the breakdown of unsaturated fatty acids and declining skin antioxidant defenses. While it starts around 40, it becomes more noticeable in the 50s and beyond.
Experiencing a noticeable odor immediately after a shower usually happens because moisture gets trapped in the groin area, causing sweat and bacteria to react quickly with your skin or clothing. The groin has many sweat glands, and some fabrics hold onto odor even when clean.
A declining sense of smell is strongly linked to dementia and Alzheimer's disease. Because olfactory and memory pathways are heavily intertwined, damage to these areas often precedes typical cognitive symptoms. Testing a person's ability to identify and distinguish different odors serves as an important, non-invasive early warning sign.
While it might come and go (or you may become so used to it that you no longer notice it), it's not fixed even if the smell dissipates for a while. A professional plumber can diagnose the problem and recommend a fix, so everyone in the house can breathe easily again.
You can also add a mixture of baking soda and vinegar along with hot water to help get rid of the odor. Pour one cup of baking soda down the drain followed by one cup of white vinegar. Let the mixture sit for about 10 to 15 mins and flush with hot water. After this you should have an odorless clean drain!
Bleach works well to sanitize and deodorize a drain – and is particularly effective when you have mildew or biofilm build up. However, you should always use bleach with caution – consistent use can damage some pipes.
Miele and Bosch dishwashers consistently last the longest, averaging 15 to 20+ years of operation. While a standard dishwasher lasts 9 to 12 years, premium brands like Miele are explicitly engineered for two decades of use, backed by some of the lowest repair rates in the industry.
The most common dishwasher failure is poor drainage or standing water at the bottom of the tub, which is usually caused by a clogged filter, a blocked drain pump, or a kinked drain hose. This prevents the machine from running or cleaning dishes effectively.
Yes, a 5-year-old dishwasher is usually worth repairing. The average lifespan of a dishwasher is 8 to 12 years, and a 5-year-old unit is generally past its initial manufacturer warranty but still has plenty of life left to justify the cost of minor fixes.