Rotten Egg Smell ComplaintUpdated 3 months ago

Rotten Egg or Sulfur Smell in Water

Overview
If your water smells like rotten eggs, the odor is most often caused by hydrogen sulfide gas (H₂S). This gas can occur naturally in groundwater or be produced by sulfur-reducing bacteria in wells, plumbing, or water heaters.

What It Means

• The smell may be present in both hot and cold water if it’s coming from the water source.

• If the odor is only in the hot water, it may be caused by bacteria inside the water heater reacting with the heater’s anode rod.

• While unpleasant, low levels of H₂S are generally not harmful — but the smell indicates a water quality issue that should be addressed.

The Fix

If the odor is only in the hot water, try shocking the water heater by following the manufacturer’s disinfection or sanitizing instructions. This process kills odor-causing bacteria inside the tank.

If the odor is present in both hot and cold water, testing is recommended to confirm the source. You can use a Cascadian Water Sample Kit to identify H₂S and other contaminants.

Treatment Availability

At this time, Cascadian does not offer treatment systems for hydrogen sulfide.

For ongoing sulfur or odor issues, we recommend contacting a local water treatment specialist who offers H₂S-specific filtration or oxidation systems.