The Health Department has set an advisory level for manganese at 0.300 mg/L (milligrams per liter) to protect the nervous system. If the manganese level in your water is more than (>) 0.300 mg/L, the Health Department recommends treating your water.
If the manganese level is between 0.050 mg/L and 0.300 mg/L, there may be:
- A metallic taste
- A bad smell
- Rusty-colored water
- Mineral deposits on toilets, sinks and bathtubs
- Sedimentation (for example, small particles of iron settling at the bottom of a water glass)
- Brown or black staining on laundry or surfaces that come in contact with the water
None of these pose a health risk. Generally, manganese concentrations below 0.050 mg/L will not cause staining or a bitter taste.
Need help understanding your drinking water test results? Find out how to read your results
