The smell of sulfur in well water is identified by an odor that resembles rotten eggs or sewage gas. The cause of the smell may be from sulfur occurring naturally in the environment, from bacteria and other organisms, or from broken or corroded pipes and fixtures.
Sulfur may be naturally present in the water as a result of dissolved hydrogen sulphide gas. Certain bacteria also release this odor. Oxygen-depleted water and algae may also cause a sulfur-like odor. A scum or mold accumulating in plumbing fixtures can identify the presence of bacteria and algae in the water, which may also have a cloudy appearance or chemical taste.
An odor originating from the entire house is normally due to a problem located throughout the entire plumbing system. Smells from one fixture or from hot water generally indicate a broken pipe or a corroded anode in the hot-water heater.