Lately I have noticed a sulfur smell in my water. What is it, and what can I do?

This usually comes from one of two sources: If you notice the smell only in your hot water then most likely your water heater is the culprit. In many water heaters the anode rod is made of magnesium. As the anode rod breaks down (which is what it is designed to do) it can create hydrogen sulfide, which produces the sulfur smell. A magnesium rod can be replaced with an aluminum rod to eliminate this problem. The sulfur smell problem can also be caused by sulphate-reducing bacteria, which thrive in the warm environment present in a water heater. To reduce the bacteria you can add hydrogen peroxide to the tank (approx. 1 pint/40 gallons of water), re-pressurize it, run 2-3 gallons of hot water at each fixture and then let it set for at least one hour or, preferably, overnight. This will help clean the tank and piping of bacteria. While the mixture is non-toxic at this strength, it’s still recommended you run a hot water tap the next day until it runs cold then wait an hour and drain the water heater. Finally, check the temperature of the hot water as soon as the burner shuts off. If necessary, lower the temperature to 125 degrees. This limits the growth of odor-causing bacteria, limits the formation of scale and is safer for everyone using hot water. An added bonus, it lowers your operating costs as well. If you notice the sulfur smell in both your hot and cold water then it's probably due to well water. Hydrogen sulfide is formed from decomposing underground deposits of organic matter like decaying plants. It can occur in deep or shallow wells and is the result of bacterial action that reduces sulfates in water to hydrogen sulfide. The simple solution for this is to chlorinate the entire water system - starting from the well, all the way through the distribution lines. Chlorine should be kept in the system for several hours, preferably overnight. If the problem persists, then you may have to install an ion exchange system. If you have very high levels of hydrogen sulfide (over 5ppm) then you may need to utilize a combination of chlorine feed, aeration and ion exchange. It’s important to note that high levels of chlorine can cause damage to your pipes and are toxic in concentrated forms. Home Page | FAQs | Glossary | Contact Us