What Do You Do When Your Water Smells Like Rotten Eggs?

If your cold water smells like rotten eggs, the odor is usually caused by the levels of sulfur bacteria and hydrogen sulfide gas that can be found in a building’s water supply. If you only experience the smell when using your hot tap, it may be a chemical reaction occurring inside your hot water heater, and not a problem with your water supply.

Is it Harmful?

Despite the wretched tingling in your nose you might experience, hydrogen sulfide is actually a non-health risk. If anything all it does is provide an extreme nuisance when found in your water supply. That being said, let’s figure out a way to get rid of your disgusting smell. Having high levels of hydrogen sulfide can damage your home’s plumbing system. The chemical can corrode pipes and plumbing fixtures.

What does it mean if your water smells like rotten eggs?

If you have hydrogen sulfide in your water supply, the main reason your hot water can smell like rotten eggs, it can damage pipes as it corrodes many different types of metals and can also cause black stains on silverware and plumbing fixtures. In most cases drinking water that has a strong rotten egg odor, although particularly unpleasant, is perfectly safe to drink. However in some rare occasions the odor may be caused by sewage or other contaminates in a building’s water supply, which could cause health problems.

What Should You Do if you Smell Rotten Eggs?

If you do experience any new odors it is always important to find the source of the problem by checking taps and water supplies around the building.

The first step to find out what to do when your water smells like rotten eggs is to see if the odor is from hot water only, or if it is also coming from the cold well water.

Run a hose bib or tap as close to the well as possible and fill a 5- gallon bucket or other container and notice if there are odors. If you smell a “rotten egg” odor, this is hydrogen sulfide gas. If the water smells like oil or asphalt this can be from manganese. If your water smells like cucumber or sewage this is usually a result of iron and/ or sulfur bacteria. Run the hot water from each tap and notice if there is an odor in the hot water that is not apparent in the cold water.

Hot water:

If your hot water smells like rotten eggs, it is likely because of your water heater. Contact a trained boiler inspector to see how this can be fixed. Sulfates in water, as well as iron and sulfur bacteria can interact with the anode rod in water heaters. This creates hydrogen sulfide gas which is the rotten egg smell in water. Changing the anode rod to an aluminum rod can often solve this problem of having well water that smells like sulfur. 

If you have rotten-egg sulfur smells in the hot water only,

• Replace or remove the magnesium anode. Many water heaters have a magnesium anode, which is attached to a plug located on top of the water heater. It can be removed by turning off the water, releasing the pressure from the water heater, and unscrewing the plug. Be sure to plug the hole. Removal of the anode, however, may significantly decrease the life of the water heater. You may wish to consult with a water heater dealer to determine if a replacement anode made of a different material, such as aluminum, can be installed. A replacement anode may provide corrosion protection without contributing to the production of hydrogen sulfide gas.
• Disinfect and flush the water heater with a chlorine bleach solution. Chlorination can kill sulfur bacteria. If all bacteria are not destroyed by chlorination, the problem may return within a few weeks.
• Increase the water heater temperature to 160 degrees Fahrenheit (71 degrees Celsius) for several hours. This will destroy the sulfur bacteria. Flushing to remove the dead bacteria after treatment should control the odor problem.

Cold water:

If your cold water also smells like rotten eggs, but only from the water treated by a water softener and not in the untreated water, the problem is likely to be sulfur bacteria in the water softener. Changing the water softener solution will solve this issue or  shocking the well with chlorine and then installing a peroxide injection system with a backwashing carbon filter (see below)

Both but goes away:

• If the smell is strong when the water in both the hot and cold faucets is first turned on, and it diminishes or goes away after the water has run, or if the smell varies through time the problem is likely to be sulfur bacteria in the well or distribution system. Take note to see if the smell is coming from all of your faucets or just some in particular areas or rooms of your house. If the smell is coming from isolated areas then the problem most likely exists in these drains or pipes and not your entire water supply.

The preferred treatment methods for water that has a rotten egg smell is either a backwashing sulphur water filter or a chlorination system that usually uses a stenner feed pump.

Odor in the hot and cold water that does not decrease as the water flows

If the smell is strong when both the hot and cold faucets are first turned on, the problem is likely hydrogen sulphide in the groundwater. This could also be a sign that there is a more dangerous problem you’re your water supply. This could also be a sign that there is a more dangerous problem in your water supply. If there is an odor problem with the water supply, the first step is to determine the source. If the source of your water is a public water system and you have problems with smells in the cold water, contact your water utility, or call us for help. If the source is from the well, a general mineral water analysis is critical to selecting the right system to treat the problem.

If you are concerned about what is in your water you can purchase test kits that will check the levels of hydrogen sulfide, sulfate, sulfur bacteria, and iron bacteria.

How do you fix rotten egg smell in hot water?

1) Clear Your Pipes

Turn on all the faucets in your house and allow them to run for about 10 minutes After this amount of time, turn them off. This should clear out your pipes and hopefully the smell will cease

2) Clear Your Hot Water Heater

If you figure out the smell only comes from your hot water, then it might be wise to flush your hot water heater.

• Without turning off your water supply, find a hose to connect to your drain valve of your hot water heater. Place the other end of the hose outside in a good place where excess water can run
• After 10 minutes of draining, take a sample of the water. Fill up a cup and determine whether or not there are particles or little pieces of sediment in the cup.
• Allow the heater to drain until there are no particles present

3) Disinfect Your Water Heater

1. You can also try disinfecting your water heater which is a very simple process. Simply turn the temperature of your water heater to 160 degrees and leave it run for a couple of hours. This should kill all bacteria in your water heater

1. Shock your well with chlorine bleach or hydrogen peroxide to get temporary relief from sulfur odors. Often keeps odors away for 1 – 2 months.

2. Chlorinator: Install a chlorine injector system (chlorinator) on your wellhead for continuous injection of chlorine when the water is running. Chlorination eliminates the sulfur bacteria that cause the odor, and combined with an Air Charger self-cleaning backwash carbon filter can eliminate odors continuously and take out chlorine residual before the home.

3. Peroxide: Install the same system as a chlorinator but use hydrogen peroxide in place of chlorine bleach, followed by backwashing catalytic carbon filter. Unlike chlorine, no residual salts or residues are left in the water after water flows through the carbon system.

4. Air Charger Carbon Filter: Install an Air Charger Catalytic Carbon Filter. No chemicals are needed, however, the system also can inject peroxide to make the catalytic carbon last longer. No filter cartridges to change, carbon lasts for several years and is easy to change out.

5. Air Compressor Tank Aeration System: This injects a lot of air under pressure and can eliminate odors under certain conditions.

6. Ozone Gas: Expensive but can be very effective. Inject ozone gas under pressure to quickly eliminate sulfur odors

Improving Your Drinking Water

If you are concerned about what is in your water you can purchase test kits that will check the levels of hydrogen sulfide, sulfate, sulfur bacteria, and iron bacteria. One of the better alternatives to drinking straight from the tap is using a water filter that eradicates harmful contaminants.