Sulfur Smell in Water – Why is it there and How do I get rid of it?

Turning on the water only to be confronted with the smell of rotten eggs is a problem that nobody wants to live with. If you are dealing with the smell of sulfur coming from your water source, Culligan Water can help you find an effective solution.

The smell of sulfur comes from the presence of hydrogen sulfide. The first step is determining the source or sources of the hydrogen sulfide and then we can properly treat it.

Sulfur Smell Only in Hot Water

If you are only noticing the smell of sulfur when you are running hot water, the most likely scenario is that a reaction is occurring between the water heater’s anode rod and the sulfate ions that naturally occur in water. Water heaters have anode rods to avoid corrosion in the water heater’s steel tank. Anode rods are either magnesium or aluminum and magnesium rods are much more likely to produce odor-causing reactions. The first step to take is to determine if your water heater has a magnesium rod and if possible replace it with an aluminum rod.

If the smell continues to occur with an aluminum rod another option is to remove the rod entirely and run the water heater without a rod. This can however shorten the life of the water heater tank as it will no longer have any corrosion protection. We can add FDA-listed corrosion inhibitors to the water that will aid in prolonging the life of the tank.

Removing the sulfate ions is another option. We can remove the sulfate ions using a dealkalizer. A dealkalizer operates much like a water softener in using ion-exchange to eliminate unwanted ions, such as sulfate ions, from the water supply.

Sulfur Smell In Cold Water That Goes Away After The Water Flows

If you are smelling sulfur in the water “at first draw” which means when you first turn on the water but the smell goes away after the water flows for a little while, the most likely cause is Sulfate Reducing Bacteria or SRB’s in the well or plumbing. Sulfate Reducing Bacteria produces hydrogen sulfide by “breathing in” sulfate ions and “breathing out” hydrogen sulfide, similar to how we breathe in oxygen and breathe out carbon dioxide.

Just like the air in a room with a lot of people and no air flow will get stale, water in a section of plumbing where there is not much flow will start smelling bad when SRB’s are present. That’s why you will smell that typical “rotten egg” odor at first when the water starts flowing but will notice the smell decrease as it continues to flow.

There is a possibility, although not common, that SRB’s will be present only in the water heater tank but not anywhere else. This can happen because the water does not flush out quickly in the tank due to the amount of water that it holds. A quick and simple test to see if this is the problem is to raise the temperature in the water heater tank to 140 degrees F or higher for at least 48 hours. This will kill off the bacteria and if the smell goes away you will know it was due to SRB’s and not an anode rod reaction.

Some laboratories test for Sulfate Reducing Bacteria and field kits are also available for purchase. If Sulfate Reducing Bacteria is indeed the problem the treatment would be shock-chlorination of the well and plumbing. Repeated chlorination will be necessary if the smell returns too quickly. SRB’s are not considered pathogenic, but hydrogen sulfide gas in the air can be harmful at high levels so it’s important to address this issue.

Sulfur Smell in Hot And Cold Water That Does Not Go Away As The Water Flows

If you notice that the sulfur smell is there in hot and cold water and it does not decrease as the water flows the issue is very likely the groundwater. This is true hydrogen sulfide from the source of the water.

Culligan offers a variety of treatment options as a solution to this problem, including a Culligan Softener-Cleer Plus system, a Culligan Sulfur-Cleer or Culligan Iron-Cleer filter, or chlorine or hydrogen peroxide chemical feed and carbon filtration. The choice will depend on the level of hydrogen sulfide and other contaminants (like iron) in the water as well as the peak flow rate (gallons per minute) and the peak daily water usage (gallons per day).

Water issues can be complex and require professional analysis. While hydrogen sulfide is a likely issue, it is always good to test your water to be sure there are no additional contaminants causing the odor. At Culligan, we can help. We will do a complimentary test of your water and help you find solutions.

Call Culligan Water of Northeast Kansas today for all your water purification needs and see the difference purified water will make for you and your family.


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