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Dishwasher Smell Like Sewage: Reasons & How to Fix?

The dishwasher is directly related to food or at least the dish we used to eat. You don’t need to be highly health concerned to dislike the sewage-like smells of your dishwasher. Sewage-like smell issues are more common than you think. 

This article will explain why it happens and how you can solve the problem. Keep reading.

Dishwasher smell like sewage

The dishwasher smells like sewage when the food waste stocks in some part of the dishwasher. The drain pipe is a common culprit. The waste drain water can get back into the dishwasher when it’s not high enough. Other issues like a broken thermostat or clogged filter can cause the problem.

I can guess how disturbing sewage smells can be as a similar issue has happened in my house too. A sewage-like smell was coming from our kitchen. My mother had to cook for us and is very sensitive to smells. She could not eat food with ease just by thinking of the bad smells.

We had to change the clogged basin pipes to eliminate the issue. Let’s get back to the dishwasher. As this article is being written by a microbiology expert (that’s me), this article is going to be quite different from others. 

I will describe the actual reasons in more detail and explain the steps you can take to fix the issues.

Let’s go through some fundamentals now. First, let’s understand what sewage smell is. Sewage is where you can find all sorts of human waste. You may also notice the sewage smell is different from the poop smell.

If a weird rotting smell comes from something, that thing must be organic. Every organic object gets decomposed by millions of bacteria. The bacterias produce chemicals or gas, the main reason for the rotting smell. 

Sewage contains human waste, food waste, and other organic waste products. They decompose by the sewage bacteria and produce hydrogen sulfide and other bad-smelling compounds, which cause the sewage smell.

So, when you get a sewage smell from your dishwasher, a similar thing is happening somewhere in your dishwasher. Food waste from your dishes gets stuck in the different parts of your dishwasher. The food waste gets decomposed and causes bad smells like sewage.

So, to solve the issues, we need to find out different spots of dishwashers where food waste can build up and cause sewage smells. 

When you are getting lousy sewage smells from your dishwasher, some functions of the dishwasher may not be working. It’s also very unhealthy, and you may get diseases like diarrhea and fever from the opportunistic bacteria of your nasty dishwasher. 

Sewage smell also disturbs the environment of your kitchen. So, How can you fix the sewage smell issue? Check out the possible reasons and how you can fix the issue DIY.

The drain pipe needs a high loop:

When you start the dishwasher cycle, water jets clean the food waste from your plates, and the machine drains the food waste with a drain pipe in the back part of the washing machine. 

The drain hose is tricky and can cause sewage smell issues if the tube is not positioned correctly. 

The drain pipe needs a high loop, so when the machine drains the wastewater, the water goes through the higher part of the pipe and can not return—our bathroom commode works in the same method. 

There is an S-shaped loop that makes a one-way root for the poop.

However, the loop pipe of the dishwasher is not solid most of the time, and if the loop is not high enough, the wastewater can sit in the tube and come back inside the dishwasher. 

If you can’t find the actual issue and continue using the dishwasher, the smell will worsen daily. But luckily, the problem is easy to solve.


The dishwasher drain pipe is bendable. You can change the shape of the tube. Make a 36-inch high loop with the line and ensure the pipe stays in the same position.

This means the wastewater will not sit in the pipe and never come back into the dishwasher.

Clogged filter:

Waste products can get stuck on the filter, which causes a sewage smell in your dishwasher. The filter is inside the dishwasher, and there are more chances of contamination. So you should take that seriously.


Make sure to clean the filters as often as the manufacturers recommend. Some dishwashers need more regular cleaning while others do not need cleaning that often.

Thermostat issues:

While cleaning the dishes, your dishwasher’s thermostat keeps the water temperature at about 120 degrees Celsius. It’s essential as the hot water removes grease and makes the waste dissolve in water. 

Hot water also removes the bacteria from your dishwasher system.

But when the thermostat is not working correctly, the wastes can sit in the filter and drain pipe, causing a bad smell.


Open your dishwasher in the mid-cycle and use a thermometer to find out if the thermostat is working. If it’s not working, you need to hire a professional to fix that.

Drain pipe issue:

Sometimes waste products can be attached to the drain pipe, causing a sewage smell from your dishwasher.


You can remove and clean the drain pipe to solve the issue. In the later part of the article, we will discuss the steps to clean your dishwasher drain pipe.

Is dishwasher smelling like sewage a common problem?

Sewage smell in dishwashers is a common issue for old dishwashers. Food waste can sit in different parts of the dishwasher and cause a rotting or sewage smell from your dishwasher. Bacteria feast on food waste and produce chemicals and gasses that smell like sewage.

When you are not removing the bacteria and continuously using the dishwasher, you are feeding the bacteria and helping them grow, leading to more sewage or rotten egg smells.

Check out if the following dishwashers cause a sewage-like smell.

Bosch dishwasher: 

Bosch dishwashers can cause a sewage-like smell if you do not maintain them well. But they have easy ways to run a cleaning cycle which is enough to remove the odors most of the time.

Whirlpool dishwasher: 

Whirlpool dishwashers can also have sewage-like smells, but they have clear guidelines to check different parts of the dishwasher to remove the smell.

GE Profile dishwasher: 

Like most dishwashers, GE profile dishwashers can also smell bad. But there are easy ways to fix the issues.

Can sewage back up into dishwasher?

Sewage water can not directly get into the dishwasher usually. But if the dishwasher waste water traps in the drain pipe or other place, the water gets contaminated and becomes similar to sewage water. 

The sewage-like water can enter the dishwasher if the drain pipe is not correctly positioned. 

To ensure your dishwasher drain pipe is appropriately positioned, check if the tube has a loop and if the loop height is at least 36 inches from the ground. The wastewater can not come back into the dishwasher when it passes the loop.

How do you clean a dishwasher drain line?

Cleaning the dishwasher drain line can sometimes solve all the bad smell-related issues. It’s easy to do but a bit messy, so first, check all other possible causes for the sewage smell. Check the filter and air spaces of the dishwasher. 

The drain hose may cause a problem if you cannot find anything in the filter.

Some dishwashers have easy self-cleaning methods. Perform a rinse cycle; if that does not work, you must remove the pipe and clean it manually. Check out the steps to clean the dishwasher drain line.

Check the hose:

The dishwasher’s drain hose is located behind the dishwasher. Look at the hose closely. Make sure the pipe is in the correct position and not twisted. 

Remove the drain hose:

Read the manufacturer guide to learn how to open the draining hose without hurting it. Remove the drain hose from the dishwasher. You may need to see some dirty stuff, be prepared with a mask and gloves.

Clean the hose:

Remove the dirt stuck inside the drain hose. Clean the hose with a mixture of the same parts of vinegar and baking soda. 

Rinse the pipe:

Rinse the pipe well and install it again as it was. 

Final Thoughts

Dishwashers can smell like sewage or rotten eggs when food waste does not drain well. Look for the waste build-up in different dishwasher parts and clean that thoroughly. Dirty filter and drain hose issues usually cause sewage-like smells from the dishwasher.