One of the more complaints about well water is that there is a bad odor in the water. Homeowners most often describe it as a sulfur or “rotten egg” smell. Read on to learn more information about what could be causing the smell. Additionally, learn what might fix it in your private water well.

What is that Smell?

Water with a rotten egg smell most commonly contains hydrogen sulfide. It is not typically an immediate health risk. Typically, it is detectable, unfortunately, by your nose, at relatively low levels in your water supply. It can be present in groundwater, then the pump pulls up into the water system.

Determine the Source

First you need to check if the smell in only in the hot water or if it is in the cold water as well. This is done easily enough. First go to any tap inside the home and run the hot water for a few minutes and take notice of the odor. Then do the same with the cold. Is the smell in the cold water as well? If the smell is only in the hot water, this would indicate the problem is in the water heater. If it is also in the cold, then the issue is in the water supply.

Water Heater Issues

If the issue is the water heater, it is likely that your water heater uses a magnesium corrosion control rod. Typically switching this to aluminum or some other metal will resolve this issue. It should be noted however, that switching this yourself can result in voiding the manufacturer warranty on the water heater.

Water Supply Issues

If your issue is in your water supply, it is important that you test the water for certain contaminants to verify the cause and the amount of contaminant in the water. The water should be tested for pH level, manganese, iron, hydrogen sulfide, sulfate, tannin, and total dissolved solids.

  • Sulfur smell but no iron or manganese, it is best to install a carbon filter with a peroxide cleaning kit.
  • Sulfur odor and iron and rust staining, install a chlorination followed by an iron filter.
  • Extreme sulfur odor in the cold water, it is recommended to shock the well with chlorine, then install a peroxide injection system with a back-washing carbon filter.

For More Information

For more information about hydrogen sulfide and well water smells, go to As always, if you have any issues with your system, contact our professionals at Accurate Drilling for assistance.