CALL TODAY 1-800-441-6281

CALL TODAY 1-800-441-6281

What's That Rotten Egg Smell in My Water Hydrogen Sulfide Facts

What's worse than rotten egg smell when you reach for a glass of water?

When your water has a bad odor or taste, it can be hard to ignore, especially when that smell is as noxious as that rotten egg smell.

This unpleasant smell is caused by the presence of hydrogen sulfide (H2s) in your water. It is not harmful to your health, but hydrogen sulfide can make your water corrosive, which means it can damage a home’s metal plumbing elements, like copper, iron or steel pipes. It can tarnish silverware, copper and brass utensils, as well as leave yellow or black stains on your kitchen and bathroom fixtures.

Here are some facts about hydrogen sulfide so you can better understand this pesky well water problem.


When underground organic matter decays, it can chemically react with some sulfur-containing minerals in the soil and rock, creating hydrogen sulfide in the groundwater. Sulfate, another form of sulfur, is a naturally occurring mineral in the soil and rock formations that is picked up by water as it flows through the ground. Certain types of bacteria, called "sulfur bacteria" or "sulfate-reducing bacteria," can change sulfate and natural organic materials to hydrogen sulfide gas.

Water heaters can sometimes be the source of hydrogen sulfide gas if it uses a magnesium rod in the tank. The magnesium in the rod chemically converts naturally occurring sulfates to hydrogen sulfide. Water heaters have also been known to develop hydrogen sulfide in the cleaning resin.

Is it OK to drink water with hydrogen sulfide (H2S)?
In most cases, yes, although it may not be very pleasant. The levels of hydrogen sulfide found in water is not hazardous to your health, but if the water also has a funny tastes besides rotten eggs, such as it tastes like medicine or is sweet, that could mean other contaminants are in the water that could be hazardous.

How do I know if it’s hydrogen sulfide (H2S)?
The rotten egg smell of hydrogen sulfide gas can be detected at very low levels, but your treatment options depend on the amount of hydrogen sulfide in the water, so testing is recommended. Massachusetts and New Hampshire both offer state testing for a small fee. However, because hydrogen sulfide is a gas released into the air once the water comes out of the faucet, testing can be tricky. Skillings & Sons recommends having us or another water systems professional conduct the test so that the results accurately reflect the amount of hydrogen sulfide in your water.

How do I find the source?
Is the smell coming out of both of the hot and cold water faucets, or just one? Is the smell coming only from the water treated by your water softener? Does the smell eventually go away as you continue to run the water, or is it constant? Answering these questions will help pinpoint where the hydrogen sulfide or sulfate is coming from.

How can I remove it from my water?
If the source of the problem is a home well, flushing the casing with a strong chlorine solution can usually address the problem. If the problem is in the groundwater, though, flushing will only be a temporary fix. The same goes for flushing your water heater.

If hydrogen sulfide originates from your ground water, an active carbon filter can solve the problem if contamination levels are low. If there is a moderate amount, an oxidizing filter will convert the hydrogen sulfide into sulfur, which can easily be filtered out. For high levels of hydrogen sulfide, you can install an oxidation-filtration system, which works similarly to an oxidizing filter.

Skillings & Sons can identify the source of that rotten egg smell in your water and help you find the solution that best works for your home.