3 Reasons Your Well Water Smells Like Sulfur

You’re hopping into the shower after a long day, only to be hit with a pungent odor that can only be described as the smell of rotten eggs. You know deviled eggs aren’t on the menu tonight, so why does your well water smell like sulfur? As it turns out, this is a common phenomenon, but it’s not something you have to live with. Here are three reasons that your well water smells like sulfur, plus how to fix it.

1. The Smell Is Coming From the Ground

A sulfuric smell doesn’t always mean that something is wrong with your water. This smell can occur naturally from hydrogen sulfide gas (H2S), which occurs naturally when organic matter breaks down in the soil. This smell can leach into the groundwater that’s eventually pumped throughout your home.

2. Bacteria Are in the Well or Plumbing

The sulfur smell can also originate in the well itself or in your plumbing. Microorganisms known as sulfur bacteria release H2S, and they thrive in dark, wet wells and plumbing pipes. This smell can be released with the water when you turn on the tap.

3. The Smell Is From Your Water Heater

Sulfur bacteria aren’t limited to the well or the pipes around your home. The warm, moist environment inside a water heater is similarly ideal for sulfur bacteria to thrive and release H2S gas. However, water heaters can also produce H2S through a chemical reaction between the magnesium metal inside the anode, which helps reduce water heater corrosion, and sulfate that naturally occurs in the well water. 

A pro can help find an anode made from other metal materials to reduce odors, or they can suggest ways to kill the sulfur bacteria with chlorine or high heat. Because chlorine or high heat can pose risks to human health, like respiratory irritation or burns from hot water, it’s best to leave these solutions to a pro.

How to Get Rid of Sulfur Smells in Well Water

Now that you know why well water smells like sulfur sometimes, you can learn how to fix it. There are several steps you can take to get rid of the unpleasant (but often harmless) odor and confirm that the water is actually safe from other contaminants.

Test Well Water Regularly

One of the most important things to do, whether your well water smells like rotten eggs or not, is to test your well water regularly. Test your well water at least once per year for bacteria and contaminants such as E. coli and nitrate. 

If your water suddenly starts smelling like sulfur or other odors or looks or tastes different, schedule a well inspection to be sure the water is safe. A well inspection costs $250 to $550 on average.

Shock the Well

Shocking a well is a process where you add chlorine to the well to help remove contaminants and bacteria, including sulfur bacteria. Shocking a well costs $80 to $200, and it’s worth adding to your budget if you want to get rid of sulfur smells in a well. 

You should shock your well at least once per year, but consider leaving this job to the pros during the annual well inspection to ensure you don’t add too much chlorine to the water. If chlorine in tap water exceeds 4 milligrams per liter, it could damage your plumbing. Too much chlorine in your water could also pose health risks, such as respiratory irritation, coughing, dry skin, and difficulty breathing, according to the U.S. Centers for Disease Control and Prevention.

Consider Aeration

If the source of the smell is coming from the groundwater, aeration can help push the H2S gas out of the well by pumping air into the well. This solution can help reduce sulfur smells from the well and get rid of iron bacteria, which can cause rust-colored stains, discolored water, and musty-tasting water when left untreated.

Install Water Treatments

Another option to mitigate the smell and taste of sulfur bacteria in water is to use water treatments, such as activated carbon filters, for your plumbing. Activated carbon filters can help neutralize odors if you have less than 1 milligram per liter of H2S in the water, and oxidizing media filters can help mitigate smells from H2S levels of up to 6 milligrams per liter.

Drill a New Well

If your well is more than 25 years old, it may have a buildup of decaying matter and sulfur bacteria that are difficult to fully eradicate. If you’ve installed water treatments, disinfected the well, and aerated the well and still notice the well water smells like sulfur, it may be time to hire a pro to drill a new well or upgrade some of the parts of the well, such as replacing the well tank.

Consult a Pro

The best way to find the source of sulfur smells in your well water and treat them is to hire a well and pump contractor near you. A pro will come to inspect the well, well pump, and plumbing to find out where the bacteria and H2S gas are building up. Then, they can decide which treatment will be most effective. Not only will this save you time on treatments that aren’t targeting the source, but it will ultimately save you money, too.