The sulfur smell in well water is due to the presence of the gas contaminant, hydrogen sulfide (H2S). This gas is a common contaminant of well water and is usually produced by certain types of bacteria as a waste product. Hydrogen sulfide gas produces an offensive “rotten egg” or “sulfur water” odor and taste in the water. Two forms of sulfur are commonly found in drinking water supplies: sulfate and hydrogen sulfide.
In some cases, the odor may be noticeable only when the water is initially turned on or when hot water is run. Heat forces the gas into the air which may cause the odor to be especially offensive in a shower. Occasionally, a hot water heater is a source of hydrogen sulfide odor. The magnesium corrosion control rod present in many hot water heaters can chemically reduce naturally occurring sulfates to hydrogen sulfide. Read more…