Manganese in Drinking Water

Manganese is a naturally occurring metal found in rocks and soil in Vermont. Manganese dissolves from the bedrock into the groundwater that fills wells drilled into or close to these rocks. Some common dietary sources of manganese are nuts, tea, leafy greens, and whole grains. Your daily intake of manganese will depend on your food choices and includes the water you drink.

There is no federal Maximum Contaminant Level (MCL) for manganese, but there is a secondary MCL for manganese of 0.05 mg/L. This is considered an aesthetic level, meaning that water with manganese levels over 0.05 mg/L could lead to staining, or a blue color, on bathroom fixtures or laundry.

The Vermont Department of Health has a health advisory level for manganese of 0.3 mg/L to protect the nervous system.

The Health Department recommends testing your private water source for manganese and other contaminants. Find out what you should test

Health Effects of Manganese in Drinking Water

Manganese is an essential metal required for many metabolic and cellular functions. Small amounts of manganese are added to most vitamin supplements and baby formulas to make sure people are getting some manganese in their bodies.

However, exposure to too much manganese over a long period of time could harm your nervous system. Studies suggest that babies may be especially sensitive when fed formula made with well water that has high amounts of manganese.

Treatment Options

Water treatment can help remove manganese from your drinking water. You can choose one of the following treatments:

  • Specialty filters that remove manganese as the water flows through the filter
  • Oxidation filtration treatment that uses chlorine, air, or peroxide followed by a filter
  • Water softeners

Call a water treatment professional for details. Filter or softener treatments generally include a backwash where the manganese and other impurities are flushed to a household drain. Do a follow-up manganese water test to make sure the treatment worked and manganese is below the Vermont health advisory level.