Manganese in Drinking Water
EPA limits, health effects, and what to do if your water is affected.
🩨 Health Effects
No federal primary MCL, but the EPA recommends keeping levels below 0.3 mg/L and has a secondary standard of 0.05 mg/L for aesthetics. Emerging research suggests long-term exposure above 0.3 mg/L may affect neurological development in children and infants.
📍 Sources in Water
Manganese occurs naturally in soil and rock and is common in groundwater, especially in low-oxygen conditions. It also enters water from industrial discharge and natural sediment disturbance.
✅ What To Do
Oxidation followed by filtration is the most effective treatment. Water softeners can help but are not ideal for manganese. Contact your utility if concerned. The EPA is evaluating whether to establish a primary health-based MCL.
Check your tap water for Manganese
Search your ZIP code to see if your water system has had Manganese violations, plus lead testing results and an overall safety grade.
Search your ZIP code →Data from the EPA's Safe Drinking Water Information System (SDWIS). MCLs reflect minimum federal standards; some contaminants may pose health risks below these thresholds.