That “rotten egg” odor coming from your tap water can really put a damper on, well, everything—from pasta nights to morning showers.
Luckily, while the sulfur smell in well water is an unpleasant odor, it is treatable. In most cases, the smell comes from hydrogen sulfide, a sulfur compound gas made from sulfur bacteria. In this guide, we’ll outline how to diagnose your foul water smell, improve water quality, and rid your house of contamination.
Before you get your tool belt out from the far corner of the coat closet, you must first find out where the stench is coming from. In general, there are two ways to diagnose and figure out how to get rid of the sulfur smell in water:
The solution you choose will depend largely on where the problem is occurring and how much mg/L of hydrogen sulfide is in the sulfur water. While the smell is often an indicator of the presence of hydrogen sulfide, you can also test levels by:
Alternatively, the issue could also be due to iron bacteria—although it’s less common. This type of bacteria appears on surface waters and deposits “rusty” bacterial cells that can stick to plumbing.
The foul odor may be emanating from your hot water heater since many types of bacteria thrive in warmer temperatures. Usually, an anode rod works within the water tank to eliminate impurities. However, over time it may become corroded and stop working, leading to sulfur-like smells.
As such, you’ll want to sanitize and inspect the heater to prevent further contamination if you notice a sulfur-like smell coming from the tank.
Sulfur-reducing bacteria thrive in hot water environments like a hot water heater. When these types of bacteria consume sulfur, they can produce high levels of hydrogen sulfide, producing a rotten egg smell.
Once these bacteria are established in the tank, you’ll have to sanitize the tank to remove them:
Quick Tip: Servicing your hot water heater on your own is not recommended as it may be dangerous, violate the warranty, or make the problem worse.
To stave off corrosion, most hot water tanks are equipped with at least one magnesium anode rod on the inside. This rod, aptly known as the “sacrificial anode,” pulls corrosive ion deposits out of the water, keeping them away from the inner surface of the tank.
However, the rod is not impervious to damage and eventually will corrode beyond the point of functionality, down to a skinny wire. In this corroded state, the rod’s interactions with the sulfates in the water form hydrogen sulfide gas, causing an unpleasant sulfur odor.
Whether or not this is a result of an exhausted anode rod, is something you’ll have to inspect for yourself or with the help of a professional by following these steps:
If you’ve inspected your hot water tank with no success or both your cold and hot water have that rotten egg smell, then it’s time to look into water treatment at the source: the well. The sulfur smell in well water can be eradicated with numerous treatment methods.
Quick Tip: Sulfur bacteria is a stubborn nuisance to deep water containers. In preparation for treatment of the contaminated water, it is recommended that you give the inside of your well a thorough scrubbing with a well-cleaning kit.
Implementing a chlorination or peroxide shock will disinfect the tank by killing the bacteria present. Both chlorine and peroxide are good options. However, a peroxide treatment will more effectively stave off any unpleasant stenches.
Additionally, when using chlorine, you’ll most likely need to regularly replenish the tank and consider installing an active carbon filter to remove any excess chlorine still in the well.
This temporary solution will last anywhere from one to two months. Although if it works, you’ll know that hydrogen sulfide is the culprit.
Chlorine can remove medium to high levels (amounts higher than 6 mg/L) of hydrogen sulfide through oxidation. Using a feed pump, chlorine can be added to your water continuously to rid it of hydrogen sulfide.
Rather than a one-time shock, the feed-pump method keeps your well continuously sanitized.
Through oxidation, the chlorine converts (soluble) hydrogen sulfite into (insoluble) sulfur, at which point a water filter can easily sieve it out of the stream before getting into your pipes and home.
Bonus Points: Chlorine also keeps your water supply equipment nice and clean.
Similar to chlorination, potassium permanganate cleans the tank by making contaminants insoluble. These include:
The solids are then easily sifted out before ever having the chance to stink up your home.
When implementing potassium permanganate, make sure you replenish the well continuously and perform routine cleaning to backwash the filtration system.
Warning: Potassium permanganate is a poisonous compound and a major skin irritant. When using it, follow the handling instructions carefully and store it in a safe place where little ones and pets can’t get to it.
Sometimes your water system just needs a little bit of fresh air—if the amount of sulfur in your water is 2 mg/L or lower, then aeration could be the best option for you.
Sulfur bacteria thrive in oxygen-deprived environments. The aeration method uses an aerator to inject oxygen into your water supply, forcefully displacing hydrogen sulfide gas and creating an oxygen-rich environment that is less hospitable to sulfur bacteria.
Quick Tip: When nearby the aeration site, you’ll still be able to smell a sulfur stench. However, ventilation may help reduce the problem.
Using a charged resin, ion exchange is a way of pulling hydrogen sulfide out of the water in exchange for chloride. A salt solution replenishes the resin’s charge after depletion. While the process of an ion exchange water filter is similar to a water softener, it’s not the same.
Quick Tip: Not all resin can withstand sulfides, so it’s important to consult a professional to choose the right option for you.
A relatively effective, efficient, and safe choice for oxidizing hydrogen sulfide is ozone. No additional chemicals or filtration is required.
Instead, ozone is generated in a container and injected into the water source. The oxidizing effects of the ozone turn hydrogen sulfide into filterable, insoluble sulfur while killing:
Often used in conjunction with one of the other water filtration methods and solutions mentioned, carbon filters are often installed under sinks to treat drinking and cooking water that has small amounts of particles that need to be removed—say, less than 1 mg/L.
The activated carbon adsorbs the hydrogen sulfide after it’s insoluble. On its own, this is an economical choice for people dealing with small amounts of hydrogen sulfide.2
Quick Tip: This method requires routine replacements of carbon filters, which have varied and unpredictable lifespans.
The smell and taste of hydrogen sulfide-affected water can be so offensive that many people consider it undrinkable. While the odor might make you think it’s poisonous or toxic, it’s not.
While hydrogen sulfide is lethal in large, concentrated amounts, there is no concern with regard to the amount found in water systems.
Furthermore, the EPA categorizes water contaminated by hydrogen sulfide as a secondary, or merely aesthetic, concern. For reference, the EPA has two standards for water, primary and secondary:
Foul-smelling water can disrupt the natural flow of things within your household, but with careful inspection and precision, your water can smell rain-fresh in no time.
If you want to keep your water clean, recruit the experts at Rayne Water.
We offer groundwater and well inspections, so you can stop pinching your nose and start enjoying your life. Wondering why your tap water is yellow or brown? There might be tannins in your water. From sulfur to limescale, Rayne Water is your solution.