What Can Cause Taste or Odor in My Water?
Geosmin and MIB
Geosmin and Methylisoborneol (MIB) are harmless, naturally occurring compounds produced by bacteria in soil and algae found in surface water (lakes, rivers, streams, dams). They can produce an earthy, musty-type odor/taste, like that of overturned rich soils, and are present in foods such as beets, spinach, and mushrooms. Geosmin and MIB are NOT the result of pollution or contamination of our source waters and is not a result of a failure of treatment processes. It occurs through a natural process.
Although these chemicals are harmless, the human senses of taste and smell are extremely sensitive to them and can detect them in the water at concentrations as low as five parts per trillion (nanograms per liter). To put it in simpler terms, that would equate to one-half of one cent in a billion dollars.
What are the Effects of Geosmin and MIB?
Geosmin and MIB produce a musty, earthy smell and taste in drinking water, however both compounds are not harmful at levels present in drinking water.
What Causes Increased Levels of Geosmin and MIB?
Some kinds of algae and bacteria present in lake and reservoir water naturally produce geosmin and MIB. An increase in this production typically happens during late summer into early fall when water temperatures are warm.
What Can be Done About Geosmin and MIB?
Geosmin and MIB cannot be removed from water using normal treatment processes; advanced treatment is required. First Utility District monitors for geosmin and MIB in the drinking water supply. Beginning in late spring and through fall, during the time of year that the compounds are typically at higher levels, Powdered Activated Carbon (PAC) is added to reduce geosmin and MIB as source water enters our treatment facilities.
Can I Do Anything to Make My Water Taste Better?
When Geosmin and MIB are noticeable, customers can add lemon juice and chill water in the refrigerator to improve the taste and reduce odors.
How Long Will the Taste and Odor Last?
It is not possible to predict the onset of an incidence of geosmin/MIB, or how long it will last. FUD will continue monitoring levels in the source water and adding PAC during treatment. Since geosmin/MIB are naturally occurring, they will diminish in the water supply with time and weather changes. The temporary change is anticipated to last days to weeks but could last longer depending on surface water temperatures and the weather.
Other Causes of Taste or Odor in Water:
- Taste and odors in water are generally due to what the water has come in contact with and not the water itself. FUD tests both the raw water (before treatment and filtering) and the finished water (before being pumped to your home) for many chemicals and substances that can cause taste and odor problems.
- Residential plumbing consists of metal, plastic, and rubber materials. Water passes through these materials and can pick up tastes and odors from being in contact with them. If your water taste or odor is different than your neighbors, the likely cause of the taste or odor is in your private plumbing.
- Ice that has been sitting for long periods can become stale and can contribute to tastes and odors in water. Please throw out old ice and clean your ice maker.
- Allowing the water to run for a minute will sometimes remedy the issues associated with taste and odor problems in residential plumbing.
First Utility District is not responsible for a customer’s plumbing. We cannot repair it for you. You will need to contact a plumber. First Utility District operates the water system up to your meter. All plumbing and fixtures on your side of the meter are your private property and responsibility.