Why Does My Sump Pump Smell? Common Causes & Solutions

Sometimes my friends and neighbors will ask “why does my sump pump smell?” Well, like most people they don’t think about their sump pump very much. So, as the saying goes “shit happens.” That is especially true if the sump pump is used for a basement toilet. Which might have you asking “why does my sump pump smell like poop?”
Of course, the other common use for a sump pump is to remove water from the basement to keep it dry.

If you have noticed a foul smell coming from your sump pump, you are not alone. This is a common issue that many homeowners face. A sump pump is an essential tool that helps protect your home from flooding by removing excess water from your basement or crawlspace. However, if you are wondering “why does my sump pump smell,” it could be a sign that something is wrong.

There are several reasons why your sump pump may be emitting an odor, and it’s important to identify the source of the problem to prevent further stink. One of the most common reasons is a lack of use. If the water in the pump has been sitting stagnant for a while, it can start to produce a musty smell. Another common cause is mold and mildew growth, which can occur in damp environments. This can lead to a foul odor that can be difficult to eliminate.

Other causes of sump pump odors include a damaged or malfunctioning pump, a clogged discharge line, or a sewer backup. If you are experiencing a foul smell coming from your sump pump, it’s important to take action right away to prevent further damage to your home and ensure that your sump pump is functioning properly. Keep reading to learn more about the common causes of sump pump odors and what you can do to eliminate them.

Why Does My Sump Pump Smell? Causes of Sump Pump Odors

If you’re experiencing a bad smell coming from your sump pump, there are a few common causes that you should be aware of. By identifying the cause of the odor, you can take the necessary steps to fix the problem and prevent it from happening again in the future.

Bacteria and Mold Growth

One of the most common causes of sump pump odors is the growth of bacteria and mold in the sump pit. This can happen when there is standing water in the sump pit for an extended period of time, providing a breeding ground for these microorganisms. The bacteria and mold can produce a musty or rotten egg smell that can be very unpleasant.

Iron bacteria is a redish slime that grows on the sump basin and sump pump. Also, it can plug up water pipes. Iron bacteria is also called iron ochre. It can have a musty or even a sewage like smell. 

To prevent bacteria and mold growth, it’s important to keep the water in the sump pit clean. You can do this by making sure that the sump pump is working properly and that there are no leaks in the pit or the surrounding pipes. You can also use a sump pump cover to prevent radon gas and smelly odors from exiting the sump pit.

Clogs and Debris Buildup

Another common cause of sump pump odors is clogs and debris buildup in the pump or the pipes. This can happen when dirt, leaves, or other debris enters the pit and gets sucked into the pump. Over time, this can cause a buildup of sludge and other organic matter that can produce a foul smell.

To prevent clogs and debris buildup, it’s important to keep the sump pit clean and free of debris. You can do this by removing any debris that enters the pit and by cleaning the pump and the pipes on a regular basis. You can also install a filter or screen around the exterior of the sump basin to prevent debris from entering.

Why Does My Sump Pump Smell Like Rotten Eggs?

A damp sump basin can also cause sump pump odors. If the sump basin is damp, any decaying organic matter may start to smell. This can happen if the sump pump is not used frequently enough.

To prevent a dry sump pump basin, it’s important to make sure that there is always water in the basin. You can do this by pouring water into the sump basin as needed.

For basement sinks just turn on the tap and let some water run. Basement toilets need to be flushed occasionally to keep the bowl and trap filled with water.

Health Risks Associated with Sump Pump Odors

When you notice a foul odor coming from your sump pump, it’s important to take action immediately. Not only can the smell be unpleasant, but it can also pose health risks to you and your family. In this section, we’ll discuss the potential health risks associated with sump pump odors.

Respiratory Issues

If you’re exposed to sump pump odors for an extended period, you may experience respiratory issues. The gases that cause the odors can irritate your lungs and cause inflammation, leading to coughing, wheezing, and shortness of breath.

Methane is a colorless, odorless gas that can cause headaches, dizziness, and nausea. If you notice any of these symptoms, it’s important to seek medical attention immediately.

Allergic Reactions

Some people may be allergic to the mold and mildew that can grow in a sump pump. If you’re exposed to these allergens, you may experience symptoms such as sneezing, runny nose, and itchy eyes. In severe cases, exposure to mold and mildew can cause asthma attacks.

The smell itself might not hurt you, but the mold and mildew that cause the smell can be. If you notice any signs of mold or mildew in your sump pump, it’s important to clean it immediately to prevent further growth.

How to Get Rid of Sump Pump Odors

Cleaning the Sump Pump

The first step in getting rid of sump pump odors is to clean the sump pump itself. Start by unplugging the pump and removing any debris or sediment from the pit. You can use a wet/dry vacuum or a scoop to remove any excess water and debris.

Once the pit is clean, use a brush to scrub the walls and the pump itself with a mixture of hot water and bleach. Be sure to wear gloves and protective eyewear while cleaning. After scrubbing, rinse the pit and pump with clean water.

Install the sump pump, turn on the power. Pour water into the sump basin to make sure everything is working properly.

Replacing the Sump Pump

If cleaning the sump pump doesn’t get rid of the smell, it may be time to replace the pump. Over time, sump pumps can become damaged or wear out, leading to odor problems. If you’re not comfortable replacing the pump yourself, it’s best to contact a expert to ensure that it’s done correctly.

Odor Removal Products

Before cleaning the sump basin and sump pump try the odor removal products available that can help get rid of the smell. One option is to use sewage sump pump odor eliminators , which are designed to dissolve in water and eliminate odors.

Another option is to use an odor neutralizer , which can be sprayed or poured directly into the pit to eliminate the smell.

It’s important to note that while these products can be effective, you might still have to clean the sump basin and sump pump for longer lasting effects.

Also, the sump basin and pump need to be cleaned as normal maintenance. So, if you are asking “why does my sump pump smell?” maybe it’s time for some maintenance.

Shown below is the Camco TST MAX RV Toilet Treatment Drop-INs. Use in sewage sump pumps or any sump pump that smells. More than 20,000 people love this product.

Shown below is the OdoBan Disinfectant Concentrate and Odor Eliminator. One gallon will make 128 quarts to spray where needed.

Final Thoughts On: Why Does My Sump Pump Smell?

If the sump pump doesn’t run all year long, then pour some water into the sump basin. Make the sump pump run until all of the old stagnant water has been pumped out. Having water in the sump basin is much better than letting it dry out.

For a quick fix use the OdoBan Disinfectant Concentrate and Odor Eliminator  to eliminate the smell. If the smell returns, then cleanout the sump basin and sump pump. That is the best way to stop asking “why does my sump pump smell?”

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