How to Get Rid of a Sulfur Smell in Water

An unusual odor coming from your water can make you question its safety. A foul smell could mean contaminants or the smell could just be a harmless nuisance. Here, we lay out the cause of the smell and what to do to resolve it.

By: Maggie Pace

Water is essential to our daily functions, and while some water quality issues aren’t that noticeable to the average person, few are as distinct as a rotten egg smell coming from your tap. Though a sulfur smell in water doesn’t always mean your water is dangerous, the foul odor is unpleasant and it could be a sign of an issue with the water heater in your home. But don’t panic — sulfur in water is a common frustration with multiple proven solutions. In this article, we’ll explore why the sulfur smell in your water develops in the first place and how you can fix this issue.



Why does my water smell like rotten eggs?

If you've ever been greeted by the off-putting scent of rotten eggs when turning on your tap, the culprit may be high levels of sulfur-reducing bacteria and hydrogen sulfide gas in your water supply. Sulfur-reducing bacteria thrive in environments with low oxygen, such as deep wells or plumbing systems, and they transform naturally occurring sulfates into hydrogen sulfide gas. This gas, notorious for its distinctive rotten egg odor, can impart an unpleasant taste and smell to your water. 

Some people experiencing this issue only have a foul smell when the water is hot, which may come from a chemical reaction with rods in your water heater. If the issue occurs in both hot and cold water, the issue may be from bacteria in stagnant water or indicate more significant contamination.

Causes of sulfur smell in water

  • Sulfur-reducing bacteria
  • Hydrogen sulfide gas
  • Corroded magnesium anode rod in the water heater
  • Pollution (though this is rare)



Is sulfur water safe to drink and bathe in?

While water that smells like sulfur is generally not harmful to health, its distinctive odor and taste can make it unappealing and may affect your overall satisfaction with your water. As for bathing, the sulfur smell can be particularly noticeable when using hot water, as the gas is released more readily in warmer conditions. Bathing or showering in water with a sulfur odor is not directly harmful, and the absorption of hydrogen sulfide through the skin during bathing is generally considered to be minor. Regardless of the low risk to your health, if you experience a persistent sulfur smell in your water, it’s a good idea to investigate and take measures to improve your water quality as high levels of sulfur compounds in water can corrode plumbing fixtures and pipes over time.



3 steps to get rid of a sulfur smell in water

If you’re tired of the smell of rotten eggs every time you get water from the tap, below are a few things you can do to examine and fix the issue.



1. Check hot and cold water for a sulfur smell

Begin by checking both your hot and cold water taps individually. During this investigation, take note of whether the smell dissipates quickly or lingers, as this information can help you understand the extent of the problem.



  • Sulfur smell only in hot water: If your water is plagued by the rotten egg smell only in hot water, this likely means your issues are starting from your water heater. This is likely due to a reaction between the anode rod — which is made from magnesium — and sulfite ions in the water. The anode rod works to protect your water heater from corrosive elements that can damage the appliance. This reaction between the anode rod and sulfite ions produces hydrogen sulfide gas that causes the sulfur or rotten egg smell in water.
  • Sulfur smell in cold water that goes away shortly after water flows: If the sulfur smell is noticeable in cold water but fades after a short time, sulfur-reducing bacteria in stagnant water may be the culprit.
  • Sulfur smell in hot and cold water that does not go away: If the sulfur smell persists in both hot and cold water without any improvement over time, it indicates a more serious contamination issue.



This initial examination sets the stage for how you should move forward to address the sulfur smell. During the investigation phase, you may also uncover other contaminants that need to be addressed. You may be able to address these through the use of a water filter like our Rhino® Whole House Water Filter, which reduces 97% of chlorine in addition to other contaminants.

2. Test your water for sulfur

While checking for a sulfur smell in the presence of hot and cold water, and seeing if it lingers can give you an idea of the issue’s cause, testing your water can confirm your theory or reveal the true problem.

If you receive your water from the city, start by examining the water quality report they provide detailing the contaminants that are present. Check for any indications of elevated sulfur levels, as this can help determine whether the problem happens during or after treatment. If the report shows high levels of sulfur, it could mean their treatment process is causing the issue. If the report doesn’t show high levels of sulfur, it means the water may be contaminated after leaving the treatment process. This could be caused by contamination in the water lines leading to your house, or in your home’s plumbing.

If you rely on water from a private well, you’ll need to test the water yourself or hire a professional to check for the presence of sulfur and other contaminants. You can buy DIY water testing kits, but a professional may be able to perform a more comprehensive test and provide advice if contaminants are found.

3. Treat the water based on your results

Depending on your results from steps one and two, below are some potential ways to address your water quality issues.

If the sulfur smell is only in hot water, the issue is likely from the magnesium rod in your water heater reacting with sulfite ions to create hydrogen sulfide gas. You can fix this issue by replacing the magnesium rod in your water heater with an aluminum rod to prevent the reaction. 

If the smell occurs in cold water and goes away quickly, the issue is likely from sulfur-reducing bacteria in stagnant water. In this case, shock chlorination, a process involving the introduction of a high concentration of chlorine to the water system, can eliminate the bacteria and mitigate the odor.

If the smell occurs in both hot and cold water and does not go away, it indicates a more serious contamination issue that may require a combination of methods to address. You can start by replacing the magnesium rod in your water heater with an aluminum rod and pair that with other methods like shock chlorination, aeration, and potassium permanganate treatment. Aeration involves exposing the water to air, allowing dissolved gasses like hydrogen sulfide to escape. On the other hand, potassium permanganate is a powerful oxidizing agent that can effectively neutralize sulfur compounds in water, eliminating both the odor and taste.

While it’s great to do what you can to identify and correct the issue yourself, we recommend contacting a local professional in your area who can confirm your issue and help you address it.



Enjoy better quality tap water with Aquasana

Addressing the sulfur smell in your water requires a thoughtful and diagnostic approach. By assessing whether the issue stems from the tap water or the water heater, testing for sulfur content, and applying targeted treatment methods based on the results — you can understand what’s causing the smell and address the issue for good.

If you identify other harmful contaminants while addressing the sulfur smell or simply want to improve the quality of your tap water, Aquasana's whole house water filtration systems can help you provide safer water throughout your house. With specialized systems available for both general water sources and dedicated solutions for well water, you can find a system for your specific needs. If the pipes in your home are a source of contamination, you can also choose from a variety of point-of-use under sink and countertop systems.

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