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Why Does My Water Smell Like Rotten Eggs?

Sink with Rotten Egg Smell in Water

One of the worst things is turning the faucet on to brush your teeth first thing in the morning and being met in the face with a pungent smell. If you’ve just been dealing with it and wondering why does my water smell like rotten eggs — you don’t have to continue wondering! We’re going over all the ins and outs of this problem (technically called hydrogen sulfide or sulfur), what it is, if it can harm you, and how you can get rid of it!

Getting Rid of the Hydrogen Sulfide In Your Water For Good

To understand how to get rid of this compound, we have to do a little digging into what it is and what it does.

What is Hydrogen Sulfide?

Hydrogen sulfide gas (H2S) often has a rotten egg smell or taste. It occurs primarily in well water but can be present in aging homes with city water.

It is produced by —

  • A naturally occurring decomposition of plants and leaves as they interact with the soil and rocks.
  • Some sulfur bacteria that is in your groundwater, plumbing system, or well.
  • A chemical reaction inside an aging water heater or water softener system.
  • Pollution (a rare reason).

How does Hydrogen Sulfide harm my home and water?

Although hydrogen sulfide does not pose a health risk, it can cause adverse effects to your home. First, the sulfur bacteria produce slime, which helps iron bacteria and other things grow in your wells, plumbing, and irrigation. The gas can corrode metal pipes and create black stains on plumbing fixtures. Additionally, hydrogen sulfide can damage septic tanks and other treatment systems. If you suspect that hydrogen sulfide is present in your water, it is essential to have the water tested by a professional.

It’s not common, but if you have high levels of hydrogen sulfide gas in the air in your home, it can be harmful. Be sure to vent your home, basement, or well pits when hydrogen sulfide gas may be in your spaces.

How do I detect Hydrogen Sulfide?

If you have that classic rotten egg smell, you may have other signs of the bacteria, such as —

  • White, grey, black, or reddish brown slime (reddish brown is iron bacteria, which often comes with sulfur).
  • Corrosion on pipes or metal appliances (signs of gas reacting with your fixtures).
  • Black stains on pipes or appliances.

If you have any of these signs, your home will benefit from a water test. Often, the rotten egg smell is only sulfur and doesn’t mean you have other hazardous contaminants, but to be safe, you want to be sure you don’t have nitrate or coliform bacteria in the water.

When you need to determine where the sulfur smell is coming from, here are a few practical steps —

  1. Begin by not turning the water on for a few hours.
  2. Turn on the cold water – is there a smell? If not, but there is with hot water, it may be the hot water heater.
  3. If you have a water softener system, run water that is not connected to the system to see if you smell anything. If there’s no smell, your water softener system must most likely be cleaned or replaced.
  4. When you run the water and notice the smell lessens after a few minutes, you most likely have sulfur bacteria in the well or your plumbing system.
  5. If the smell does not improve after a few minutes, you probably have it in the groundwater.

What do I do to get rid of Hydrogen Sulfide?

Getting rid of the rotten egg smell takes a team approach — you can use oxidizing media filtration, aeration and filtration, continuous chlorination and filtration, and ozonation and filtration, whichever is recommended by the water experts. Once you have your water tested, we can identify the right solution for your home that will take care of the sulfur and any other issues.

What should I test my well water for?

For NH wells, we recommend testing it every 1-2 years due to the current issues with PFAS, arsenic, and more. Both natural elements and human pollution can impact your well water and lead to short-term and long-term health effects. Most contaminants are tasteless, odorless, and virtually invisible.

We most often test for the following water contaminants —

  • Coliform bacteria
  • Nitrates
  • Arsenic
  • Lead
  • Manganese
  • VOCs (Volatile Organic Compounds)
  • Fluoride
  • Agricultural chemicals

If you’re looking for the purest water and want to get rid of the rotten egg smell and any other contaminants, the first step is scheduling a consultation with the NH Tap team today!


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