What do you do when your water smells like rotten eggs? Sulfur is a pretty nasty smell – it makes me gag, and I know I’m not the only one! If your water source has sulfur bacterium in it, it’ll likely travel through all the pipes and faucets in your home, but sometimes it comes out of only one faucet.
How could this be?
In This Article
What’s the source?
First, to help determine the general source of the sulfur, you must figure out if the smell comes when running either hot or cold water. Test both temperatures by running each separately for a couple of minutes. Try every faucet in your home to be sure it’s only coming from one.
If it only smells like sulfur when the water’s hot, the source is probably a chemical reaction inside your water heater. If it stinks when running cold water, it’s most likely due to high levels of sulfur bacterium and hydrogen sulfide gas in the water itself.
A sulfur smell in cold water can also be an indication of the water’s excessive hardness, which isn’t harmful. And if it smells when running both, it can signal a problem with the general source of your water: your water well or the public water supply.
If the smell goes away after a minute or two of running the water, the source is most likely a case of sulfate-reducing bacteria. This type of bacteria actually consumes plain old sulfur and then emits hydrogen sulfide. This gas is easily trapped in confined spaces such as narrow or bent pipes but just as easily flushed out with running water.
Rarely, a rotten egg smell can indicate sewage inside the main water supply, a more serious issue. In this situation, you’d need to contact your local water supply authority immediately. So if your water smells, it’s best to proceed with caution until you know the source.
How does sulfur end up in the hot water tank?
Sulfur can be found in the water heater through a couple of different ways. One possibility is a degrading anode rod, particularly ones made of magnesium. Another cause is a population of sulfate bacteria in the tank, which can form when the water remains stagnant for too long.
This bacterium loves environments with hot temperatures and little oxygen, so it thrives inside a water heater.
What does it mean when only one faucet runs smelly water?
Even when it’s just one faucet, the problem is still often one of the previous ones mentioned—some sort of sulfur bacteria buildup from one source or another. Sulfur tries to find the path of least resistance to come out of, which is sometimes through the pipes leading to one particular faucet. It’s possible a pipe to the faucet is kinked, trapping the sulfur inside its nooks and crannies.
The odor could also be an issue with something rotting inside the drain.
An easy way to check if the drain is the issue is by pouring some water in a cup from the affected faucet and sniffing it, preferably in a different room. If the water doesn’t stink, the drain is most likely the culprit. You can check for kinks in the pipes yourself by feeling and visually inspecting them. If neither of these is the issue, it’s time to treat your water sources.
How do I fix smelly tap water?
The solution to getting rid of the smell depends on the source of the sulfur. These are some possible fixes:
- Hot water flush of water heater
- Chlorine flush of water heater or well
- Water heater or anode rod replacement
- Water softener
- Home filtration system or faucet attachments
If it’s your hot water that emits the sulfur smell, the first and easiest thing is to try a hot water flush of your water heater.
Change the temperature on it to 160℉ for 8 hours, which is hot enough to kill any bacteria. Then, once you change it back and the water has cooled, drain the whole tank. Note that you should only try this method if your tank has a pressure relief valve.
Chlorinating your water heater or water well (if you have one) is a standard solution, but it’s typically an ongoing need because of how quickly the bacteria repopulates. Luckily there exists automatic continuous chlorine feeders that can consistently kill any inkling of sulfur in the water.
You can try chlorinating them yourself or hire a professional.
A complete tank replacement may help solve the issue if the sulfur smell remains after a system flush, but not always. An anode rod replacement made of another material—aluminum or titanium—can potentially solve it too.
Installing a water softener is a possible but unlikely fix. It will only work if the reason for the smell is hard water. You probably already know if your water is hard or soft, but you can still test it from that faucet.
Finally, a home filtration system can remove sulfur from your water, as well as other gross and potentially harmful chemicals. Unfortunately, installing these can be expensive and are not a possible solution for everyone. Direct faucet-mounted water filters filter the water right at the tap that nearly anyone can install.
What if I have no control over my water source?
Unfortunately, if your water supply comes directly from the city, there’s no easy or cheap fix other than filtration systems. Unless the water contains amounts of sulfur significant enough to be harmful (you can test the levels at home with a kit), the city has no requirement to change anything.
No matter how gross the water may seem, it’s still deemed safe to use when sulfur levels are under 250mg/L.
The same goes for living in an apartment building. If the water supply is technically safe, your landlord is not required to resolve the issue. It’s also much harder to rectify the issue yourself in an apartment.
The best you can really do is install faucet filters—you can’t just modify your pipes, nor can you take on the task of flushing systems that don’t belong to you.
Is it safe to shower in water that smells like sulfur?
The good news is that smelly water, while off-putting, is usually still usable and safe for both washing and consumption. Still, you should not use it until you’re positive of the sulfur source. You don’t want to find out you’ve been drinking sewage water, which is both gross and harmful!
The best course of action is to identify the cause of the smell and eliminate it immediately. Until you can locate it, consider buying bottled water to drink and cook with. Even if it’s not sewage in your water, it can still have a bad taste.
This ensures the safety and health of you and your family.