MANGANESE FACT SHEET
MCL: 0.05 mg/L
Source: Occurs naturally in ground water
Effect: Offensive taste, odor, and staining
Followup: Treat and retest
Treatment: Oxidation filters, Particulate filters, Ion exchange
Manganese can occur naturally in ground water and it is often found in combination with iron. Water percolating through soil and rock can dissolve minerals containing iron and manganese and hold them in solution
Manganese in drinking water is not considered a health problem at the levels normally found in drinking water. Even in small concentrations, manganese can cause an unpleasant taste and odor in water. Manganese can cause brownish-black stains on laundry, porcelain, dishes, utensils, and glassware. Brownish stains in dishwashers are usually the first sign of the presence of manganese. Soaps and detergents do not remove these stains, and chlorine bleach may intensify the stains. Sometimes, manganese can appear as dark brown or black particles that leave a dark brown residue when crushed.
If the water has been out of use, put the water back into use and retest. If manganese persists, install a treatment system and retest.
Ion exchange water softeners are usually effective in removing low levels of manganese. A manganese greensand filter, using potassium permanganate to oxidize the manganese, followed by an ion exchange water softener can be used to remove higher levels of manganese.
When manganese particles are present, but not dissolved, a particulate filter may be effective.
For manganese removal, an experienced water treatment specialist should be contacted.
Manganese stains can usually be removed by the same products that remove iron stains.