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My Hot Water Smells like Rotten Eggs

You turn on the hot water to wash your face and the hot water smells like rotten eggs. The nasty smell of sulfur doesn’t make you feel like you’re going to get clean while washing or showering. On the contrary, this unpleasant odor may even cause you to skip your shower and washing routine altogether. Yuck! Nobody wants to start their nightly or morning routine this way.

What’s causing the rotten eggs smell?

hot water causing a rotten eggs smell?
Don’t let a rotten egg smell ruin your day.

There are several reasons that you may notice this unexpected, smelly phenomenon. While it may seem like a dire situation, there’s no need to panic. Here are the main causes of this rotten egg smell and what you can do to stop it:

Warm Water Heater Environment Breeds Sulfur Bacteria

Unfortunately, water heaters are known for creating an environment that’s ripe for sulfur-reducing bacteria. Sulfur naturally occurs in water, as do the bacteria. When this water laden with the makings for a foul-egg smelling problem arrive in your tank, the conditions become perfect.


The anodes that are in your water heater to prevent corrosion produce hydrogen ions with which the sulfur bacteria make hydrogen sulfide gas. This isn’t always the cause of stinky water, but when only the hot water is smelly, it’s likely your water heater environment has something to do with it.

Fortunately, sulfur, sulfur bacteria, and even the pungent gas they produce are typically safe. While the smell is unpleasant, you can continue to use your water as usual without any health consequences. That being said, most people won’t be able to stomach drinking water that smells like its rotten.

Well Water vs. Municipal Source

Sulfur bacteria are more commonly found in well water than in municipal water sources. This is because the chlorination system in most municipal sources kills off the bacteria. Because there is no chlorination system for well water, bacteria are often more plentiful.

However, that doesn’t mean that municipally sourced water is free from the rotten egg smell. Depending on your location, your water may arrive without much chlorine left. In particular, old iron distribution systems can create an ideal environment for bacteria growth which quickly depletes oxygen and chlorine. Then, when the water enters your house, it’s ripe and ready to create odors.

Water Softener Can Make it Worse

If you have a water softener, this can make your smell problem worse and more difficult to manage. Softened water increases the conductivity of water, which also increases the production of hydrogen sulfide. Furthermore, water softeners themselves are known to be great hosts for sulfur-reducing bacteria. This is because water softeners don’t contain much oxygen and the bacteria prefer oxygen-deficient environments.

The worst combination is well water that’s softened. In these conditions, the onset of a smelly water problem is likely thanks to the properties of the well water and the use of the softener.

What can you do about it?

Fortunately, some solutions can help you eliminate that rotten egg smell from your hot water. However, before beginning, you should confirm that the hot water is indeed the source. Turn on the cold water for a smell test and then do the same for the hot water. If the hot water is indeed the problem, you can move forward with a solution related to your water heater.

The first course of action is to flush the water heater and sanitize it. You’ll want to call a professional water heater service company to perform this task to avoid damage to your heater.

However, if this doesn’t resolve the issue and the problem comes back, replacing your anode with a zinc-aluminum anode rod can help reduce the odor problem. In cases of a very stubborn sulfur problem, a powered anode can usually help. These rods feed electricity into the tank that prevents corrosion, eliminating the presence of aluminum or magnesium in the rod. However, because there is no chemical reaction taking place with the anode to create hydrogen ions, the bacteria can no longer make the gas that plagues your home.

If none of the above solutions work, your smell problem may have another source. With the help of a skilled plumbing professional, you can get to the bottom of the problem and find a solution.

No one wants to live with water that smells like rotten eggs. As soon as you notice the problem, call your trusted Orange County Plumber to start treating the problem. Before you know it, you’ll be able to enjoy an odor-free shower again!

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