Sump Pump Odors: Why Does My Basement Smell?

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Sump pump odors aren’t only an inconvenience — many times, these smells tell you something is amiss with your sump pump! While the nature of sump pumps means they’re never going to smell like roses, unusually pungent odors often indicate you need plumbing services.

Luckily, sump pump odors are usually early warning signs of a problem. It’s far more pleasant to discover a sump pump issue due to a foul smell rather than a flooded basement. Learn what sump pump smells say so you know when to call in a plumber. Apollo Home shares the sources behind common sump pump odors and what to do about them.

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Common Issues That Cause Sump Pump Smells

If your sump pump smells foul, these common issues are likely culprits:

  • Sewage infiltration
  • Stagnant sump basin
  • Dry sump basin
  • Basement drainage

Sewage Infiltration

When a sewer line leaks or ruptures, it is possible for raw sewage to saturate the nearby groundwater. As the sump basin collects excess groundwater, sewage that has infiltrated the basin creates noticeable sump pump smells in your home.

The bad smell of sewage from the sump pit is sometimes infrequent early on but becomes more consistent as the problem persists. Sewer line issues that lead to sump pump smells require emergency plumbing service. A plumber uses a camera to inspect the home’s sewer lines and find the location of a leak or rupture, then makes necessary repairs to prevent sewage infiltration in the surrounding groundwater and your sump pit.

Stagnant Basin

Your sump pump only runs to eliminate accumulated groundwater once it reaches a certain level in the basin. If the sump pump fails to run or its float switch isn’t properly adjusted to empty the basin fully, stagnant water creates sump pump odors.

A defective check valve in the sump pump system is another possible issue that leads to stagnant water in the sump pit. When the check valve malfunctions, water that was pumped out of the basin is allowed to flow back in when the sump pump stops — with this issue, there is always water present in the basin, which stagnates over time and causes sump pump odors.

Dry Sump Basin

During dry periods, water in the sump pit evaporates over time because the pump does not remove it. When the basin fully dries, gases escape, which causes bad smells in your home.

The sump pit needs a small amount of water at all times. If the basin has dried, fill it with enough fresh water to cover the drain lines that run out of the pit.

Basement Drainage

In homes with basement bathrooms or laundry facilities, the sump basin is sometimes used as drainage for greywater, which is the used water from your shower or washing machine. Residue from detergents and soaps can stick in the sump pit, which leads to odors. A good cleaning of your sump pump and the sump pit on a regular basis helps eliminate the smell.

What To Do About a Smelly Sump Pump

If sump pump odors are present in your home, your first step is to call your plumber for Cincinnati sump pump service. Your plumber checks to verify proper sump pump operation as well as float switch position and function to ensure the basin completely empties. If odors stem from a sump pump defect, your plumber makes repairs or replaces the sump pump if necessary; if sewage smells are present, your plumber inspects sewer lines to find possible leaks before repairs are made.

A DIY remedy to remove sump pump odors is to use a bleach solution in the sump pit.

  • Create a diluted bleach solution, 1 cup bleach for every 1 gallon of fresh water.
  • Pour the solution into the sump basin until water volume activates the float switch and the sump pump turns on.
  • Use a scrub brush to clean the walls of the sump pit with your bleach solution to reduce odors.

Because the bleach has been significantly diluted with water, solution that is not fully pumped out of the basin does not damage your sump pump. Sump pumps made of cast iron or thermoplastic are able to be safely cleaned using bleach.

Sump Pump Service From Apollo Home

If you notice sump pump odors, call Apollo Home right away. Our licensed plumbers inspect your sump pump system as well as your home’s other plumbing lines to determine the source of foul odors and make needed repairs to keep your sump pit smelling fresh!

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