Odors in water can be caused by many sources. It is necessary to narrow down the source of the odor in order to correctly diagnose its cause. For example, does the odor seem to come from all taps in your home, or just one? Do you notice it outside the home (e.g. at the hose bib)? If it’s coming from just one tap, the problem is likely originating from the sink drain and not the tap itself. This odor is commonly caused by material such as hair or food particles in the drain area. To get rid of the odor, try pouring about a half cup of liquid bleach into the drain. To prevent odors from returning, routinely flush drains with a small amount of bleach once a month or so.
Is the problem tap one that is seldom used (such as a guest bathroom)? Or, if the whole house is involved, did you recently return from vacation? Often when a sink or shower is not used for a period of time, the material in the drain remains odorless until water is first turned on. When water hits the built-up material, odor can be generated. Use the same bleach flushing suggestion as above.
If the smell seems to come from all sinks, take a glass of water from a sink into another room without water, such as your living room. Is the odor still present? If not, the problem is with the drains. Use the same suggestion outlined above for all affected drains.
Still having the issue? Is the odor coming from both hot and cold water? If it’s coming from just the hot water, your water heater or water system may need flushing. This (along with older household piping, including galvanized piping) is the most common cause of this type of odor in household water systems. Annual flushing of the hot water heater should keep the problem from returning.
Hot water heater odors can also result from having the temperature set too low. To prevent bacterial growth, hot water heaters should not be set below 120 degrees Fahrenheit. Care should be taken in homes with young children, elderly or disabled residents to prevent accidental scalding.
Some odor is naturally present in groundwater due to naturally occurring organic material in the West Coast Basin. We regularly monitor odor as a secondary (non-health related) standard, but some residents may be able to detect a certain level of “earthy” odor at various points throughout the system. If you continue to experience odor problems with your water, please contact us at (310) 325-7110 or firstname.lastname@example.org to report the occurrence and Lomita Water Division staff will investigate each situation.