What Causes Water to Smell Like Sulfur?
Ideally, water should not have a distinctive smell or taste. That is however not always the case. For people who especially use water from a well, you will t one point or another detect a sulfur smell in the water which is not pleasant at all.
A sulfur or rotten egg smell in water indicates presence of hydrogen sulfide. Hydrogen sulfide or its compounds which are naturally occurring dissolve in the ground water, or is formed by bacteria in the water heater, water softener or in the plumbing system.
To get rid of the sulfur smell in your water, you will need to install a water filter and/or replace the magnesium rod in your water heater with an aluminum/zinc one. A temporary solution is to add hydrogen peroxide in your water heater or increase the its water temperature. Draining and flushing the water heater also helps.
If the sulfur smell is noticeable more in your hot water, it means your water heater uses a magnesium rod. Sulfates react with the rod producing hydrogen sulfide gas . Replacing the magnesium rod with a zinc/aluminum one will fix the problem.
Municipal water should not have the sulfur gas smell though. If you are not using water from a well and you notice a sulfur smell in your water contact your city’s water department immediately.
What is the Source of Sulfur Smell in Water?
Hydrogen sulfide gas (H2S) is produced when bacteria break down organic compound in places with low oxygen concentration. This is usually what happens in your plumbing systems and especially in you water heater, as the bacteria thrive in warm places.
Whenever you notice that pungent sulfur/rotten eggs smell in your water, the first thing you should do is determine the source. Narrowing down on some of the usual causes will help you get rid of it quicker.
- If the sulfur smell is coming from your cold water, determine if it is coming from faucets connected to the water softener or not. If the smell comes from the faucets only connected the water softener, then the problem is in the water softener. If all the faucets have the sulfur smell, open all of them and let them run for a few minutes. If the intensity of the smell reduces, the problem is with your plumbing or the well itself. On the other hand if the smell remains as it was, the ground water is definitely the problem.
- If the sulfur gas smell is coming from your hot water, you definitely have a problem with your water heater, or even well. Heated water releases hydrogen sulfide quicker than cold water.
Is the Sulfur Smell in Water Dangerous?
While the sulfur smell in water is quite unpleasant, it is not dangerous and will not make you sick. According to a research by extension.purdue.edu, hydrogen sulfide in water causes no known health effects but high concentrations will change the taste of the water and corrode surfaces.
Even if the hydrogen sulfide will not pose any health risk to you or your family, you should have it fixed as soon as possible. To start with, the smell is not the best to live with, and secondly it has an adverse effect on your plumbing fixtures.
Hydrogen sulfide dissolved in water corrodes metals like iron, brass, steel and copper. Ferrous sulfide, which is the compound formed when hydrogen sulfide corrodes iron or steel blackens the surfaces. Sinks, washing machines, kitchenware will also stain as a result. High concentrations will also stain clothes.
How to Get Rid of Sulfur Smell in Water
Depending on what you think is the cause of the sulfur smell in your water, there are several methods you can use to get rid of it, some permanent and some temporary.
I would advise that you try some of these fixes before calling in a plumber as some are really easy, and as you already know, plumbers are not cheap.
The following are the different ways to get rid of the sulfur or rotten eggs smell from your water:
1. Drain Your Water Heater
Draining your water heater is not only good for eliminating the sulfur smell in your water, but it also extends the life of your water heater. After years of usage, sediments settle at the bottom of the water heater with adverse effects if not drained out.
The sediments reduce the capacity of your water heater causing hot water to run out fast, and also corrode the lining of the tank. If the water heater is not drained periodically, it will start leaking from the bottom as it will have been totally eaten away by the sediments, making a hole through it. Such a water heater would need to be replaced immediately.
Side note: Please see when to replace a water heater in this post.
By draining the water heater, you will drain away the bacteria as well, meaning hydrogen sulfide will no longer be produced in the tank. But how do you drain a water heater? Well, very easy:
- Turn off the heater’s cold water supply at the top of the tank.
- Turn off power to the water heater. Whether you have a gas or electric heater, you must turn off the power/gas prior to draining the tank. In the case of the electric heater, you can easily burn the element by leaving it on while you drain it.
- Connect a garden hose to the water heater’s drain valve. Take your time to locate this valve as it may be covered.
- Turn on the hot water on the nearest faucet. This will help the water heater drain faster by removing air/pressure from the system.
- Open the drain valve. Make sure that the end of the garden hose is directed in an appropriate drain or out into the driveway. The water in the tank will still be scalding hot and you need to inform everyone around what you are doing. Drain the water until the tank is empty.
- Turn on the cold water supply. Once the tank is empty, turn on the cold water to the water heater. This will stir up the remaining sediment and flush it out as the well. Let the water flow out until only clean water is coming out of the hose.
- Shut off the drain valve, refill the tank and turn the water heater on.
2. Replace the Magnesium Rod with an Aluminum/Zinc Rod
Inside your water heater is a rod of magnesium rod that runs from top to bottom. You can see the plug at the top of the tank where it is connected.
The magnesium rod is there simply for sacrificial purposes. Its main function is to extend the lifetime of the water heater. Instead of compounds in the water attacking and corroding the inner lining of the water heat, they react with the magnesium rode anode instead.
But how does the magnesium rod contribute to sulfur smell in water, you may ask? Well, a reaction happens in the water heater whereby the magnesium rode anode releases electrons that aids in the conversion of sulfates (present in water) to hydrogen sulfide.
Some people prefer to remove the anode and plug off the water heater. While that will help get rid of the sulfur smell, it will considerably reduce the life of your water heater.
The best thing to do is to replace the magnesium rod with an aluminum or zinc rod. These anodes prevents the water heater lining from corroding and do not contribute to the formation of hydrogen sulfide gas.
Replacing the water heater anode is actually not that hard. Before proceeding, release pressure from the tank and then loosen the plug with a wrench.
In some unfortunate events, the plug will be fused to the body of the heater. You can therefore not replace the rode and you will need to look for alternative methods.
3. Add Hydrogen Peroxide in the Water Heater
If you would like to kill the bacteria themselves, hydrogen peroxide or chlorine bleach solution are 2 liquids you can add in the water heater every 1 to 6 months. This is therefore not a permanent solution.
The problem with this method is how to add the hydrogen peroxide to the tank. Most people prefer creating a pressure differential between the tank and the surrounding (where the pressure of the tank is lower than the surrounding), to create a siphoning system.
This involves releasing the pressure of the water heater and adding an extra injection valve. You place the hydrogen peroxide in the injection valve and after releasing the pressure of the tank the peroxide is siphoned in the tank.
Alternatively you can unscrew the plug at the top of the tank (where the anode is connected) and add the hydrogen peroxide from there. Don’t forget to release the pressure in the tank first.
I however don’t like this process that much. The effort used to do all the modification is more or equal to that of replacing the magnesium anode with a zinc or aluminum one.
4. Crank Up the Water Heater Temperature
A licensed plumber will not set your water heater temperature at more than 120 degrees, but you can. The intention is here is to kill the sulfur bacteria.
Although the bacteria thrive in warm places, high temperatures will definitely kill them. Increase you water heater temperature to 160 degrees Fahrenheit and leave it that way for about 8 hours, or preferably overnight.
Water at 160 degrees is quite hot and you should think whether to proceed with this method or not especially if you have kids of elderly folks in the house. Modern shower and tub faucets have an anti-scald device but those without will badly scald the body.
It is best to flush put the hot water after adjusting the temperature back to its original temperature. Again, this is a temporary fix and you will need to keep doing this as the smell appears.
5. Install Water Filters
If the sulfur smell is in both the cold and hot water, filtration is something you should definitely consider. Installing water filters in your house will help get rid of the smell, albeit temporarily.
One thing you need to know about water filters is that they could also contribute to the sulfur smell in your house too. The more the filter has been in place, the more bacteria are going to accumulate, breaking down matter and in the process produce hydrogen sulfide gas.
You should therefore replace your filter frequently. For anyone looking for a permanent solution, this method will be anything but ideal.
6. Disinfect the Plumbing System with Chlorine
This is not something you can do on your own and you should therefore contact a licensed professional. If you have determined that the source of the sulfur gas smell in your water is the water softener, plumbing system or well, you should have the entire plumbing system disinfected with a strong chlorine solution.
Disinfection that involves the well will be more expensive as it will also involve scrubbing the casing of the well and also agitating the water before disinfection can begin. If the problem lies within the house plumbing or water softener the cost will be relatively lower.
7. Drill another Well
Drilling a new well in a different formation is also an option to consider. I know it sounds like a very outrageous idea but if you have exhausted all possible methods then this one is worth trying.
You should however work with a professional, who has worked in your area for a long time. They will have done this kind of thing before and will advise you on the merits and demerits of the same.