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Hydrogen Sulfide: The Culprit Behind Well Water Odor

If you’ve ever noticed a rotten egg taste or odor in your well water, the culprit behind it is hydrogen sulfide. Hydrogen sulfide gas can result from many different sources, as it can be produced naturally in groundwater or in a well, water distribution system, or hot water heater. In rare instances, hydrogen sulfide can be produced by pollution or sewage.

How does hydrogen sulfide gas form in groundwater? Organic matter decay or chemical reactions with sulfur-containing materials in soil and rock can naturally form hydrogen sulfide gas. A water heaters’ warm environment can spur hydrogen sulfide gas growth by sustaining a reaction between sulfate in the water and the heaters’ anode, or metal rod that reduces corrosion in the water heater tank. The sulfur bacteria associated with hydrogen sulfide can produce a slimy substance and allow other bacterial growth in a well, and can also corrode pipes and other components of the water distribution system. In some cases, the bacteria can cause black stains on silverware and plumbing fixtures.

The rotten egg odor can normally be easily detected in water coming out of your hot and cold water faucets. The smell is often more noticeable from the hot water faucet – and if the smell is only from the hot water faucet, the problem is likely in the hot water heater instead of a water well. If the smell is strong in both the faucets when they’re first turned on and then goes away or lessens after running the faucets for a short time, sulfur bacteria is most likely present in the well or distribution system. If the smell does not go away after running the faucet, the hydrogen sulfide is most likely in the groundwater.

In the majority of cases, the rotten egg odor does not relate to the sanitary water quality, but to be sure, you must have your well checked for coliform bacteria and nitrate at the first sign of an odor. Hydrogen sulfide is toxic at high concentrations in the air, but more likely than not, it is just a nuisance that will not cause health problems when it is present in well water. If the smell is created by sewage or other pollution, your drinking water may be damaged and unsafe. Sulfur bacteria can be difficult to remove once it is established in a well, so the sooner you contact a professional, the better. If you notice an unpleasant rotten egg odor coming from your faucet, contact SeptiCare. Based in Warrenton, Virginia, SeptiCare has been inspecting, servicing, maintaining, and repairing residential and commercial Northern Virginia septic systems since 1987.