Why Does My Sump Pump Smell Like Rotten Eggs – Comprehensive Guide

Just like all the other appliances, the sump pump also needs good maintenance. When the sump pump is not given a proper look after, it starts producing a smell similar to one of the rotten eggs and after a few times, this smell becomes unbearable which can destroy the cozy ambiance of your basement.

There are multiple reasons behind the sump pump making rotten eggs smell and the most common ones are described below along with their troubleshooting. Tag along and know all the major reasons why does sump pump smell like rotten eggs and how can one get rid of it in easy ways in just 5 minutes.

Reasons of Sump Pump Smell Like Rotten Eggs

Why Does My Sump Pump Smell Like Rotten Egg

There are plenty of reasons behind this rotten smell generated from the sump pump but some of the major reasons are as follows.

  • The sump pump pit has stagnant water
  • The drain lines are dried up

Reasons and Solution of Sump Pump Smell Like Rotten Eggs

Why Does My Sump Pump Smell Like Rotten Eggs

1. Standing Water

Every sump pump requires a certain amount of water in the pit so that it can function properly. But when too many days have passed, this stagnant water consumes the bacteria from the air and generates mold and fungus inside the pit. This causes the smell to develop inside the sump pump which smells like rotten eggs according to the reporters.

Solution of standing water to get rid of sump pump rotten egg like smell

This problem is pretty easy to troubleshoot as you just have to make a mixture with 2 ingredients that are available in almost every household. Take 1 gallon of water and add 1 cup of bleach to it. Wash the pit with this mixture in such a way that the stagnant water passes out through the drain lines. Basically, the bleach makes sure that all the bacteria is killed that have been producing a bad odor.

2. The Dried Drain Lines

This is a very common reason why your sump pump might smell like a rotten egg. If you see that the water in the sump pump is dried up then there are chances that the drain lines are also dried up and the mold developing inside these dark drain lines is generating this unbearable smell.

Troubleshooting dried drain lines to get rid of sump pump rotten egg like smell

Make a solution of 2 cups vinegar and 2 gallons of water. Run it through the sump pump in a way that it floods through the pipelines thoroughly. Moreover, you can also wash the outer part of the sump pump with this mixture as well. If you want to make this mixture stronger then add some amount of bleach to this solution so that it works wonders and helps remove the smell and fungus that has grown up in the lines.

Precautions to avoid Rotten Egg Like Sump Pump Smell

  • It is better that you clean your sump pump every now and then, at least once a month.
  • Make sure that you cover your sump pump with the lid. The lid will help to keep the smell in the pit for several days, even if you forget to wash out the stagnant water.

Frequently Asked Questions

Why does my sump pump smell like sewer?

There could be a possibility that the sump pump drain lines are mixing up with the sewerage drain lines and it is better if you call the plumber immediately if this smell doesn’t go away in a day or two.

How often should you clean your sump pump?

It is better if you clean the sump pump every month but if you can’t clean it frequently then try to clean it after every three months otherwise the sump pump will start producing unbearable smells.

Should my sump pump always have water in it?

It is totally normal for a sump pump to have some stagnant water in it. But make sure you change this water after 25 to 30 days especially in the summer period when the sump pump doesn’t perform much.

Final Thoughts

As the stagnant water can develop a weird kind of smell, clean your sump pump once a month to prevent your basement from bad odor. Keep in mind that the dried-up sump pump can create a poop-like smell so it’s better to fill the sump pump to a certain level as required and change this water every now and then. Lastly, to clean the sump pump you can use a home-based solution including bleach, vinegar, and water, and would not need any professional help.


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