What is Manganese* and Why Does It Matter?

Manganese is a naturally occurring metal found in rocks, soil, and sediment. It dissolves easily into groundwater as water moves through underground rock formations. Industrial activities like mining, steel manufacturing, and the use of certain pesticides can also push manganese into local water supplies. In older communities, corroding pipes and plumbing fixtures are another common source — manganese that has built up inside pipes can flake off directly into your drinking water.

Most people associate manganese with industrial pollution, but it's actually one of the most common naturally occurring metals in U.S. water systems. Across the country, 4,061 water systems have detected manganese, with average levels around 13.6 parts per billion (ppb). Some systems have recorded levels as high as 1,000 ppb — a staggering number that puts real families at real risk.

At low levels, manganese is actually an essential nutrient. Your body needs small amounts of it to support bone health and metabolism. But the line between helpful and harmful is closer than most people realize. The EPA's health advisory for manganese in drinking water sits at 300 ppb for adults, but the Environmental Working Group (EWG) sets its health guideline much lower — at 100 ppb — based on neurological research. Studies cited by the World Health Organization (WHO) link long-term exposure to elevated manganese with memory problems, reduced attention span, and slower motor function in children. Infants and young children are especially vulnerable because their developing brains absorb manganese more readily than adults. Of the 4,061 systems that detected manganese, 117 reported levels above the EWG health guideline — meaning thousands of households may be drinking water that exceeds what independent scientists consider safe for kids.

Geographically, manganese concentrations tend to cluster in states with older infrastructure and mineral-rich groundwater. Texas leads the country with 508 affected systems, followed by Illinois (384), North Carolina (244), Arkansas (185), and Iowa (181). These states share a combination of factors: aging water distribution systems, geology that naturally leaches manganese into aquifers, and in some cases, agricultural runoff that disturbs soil layers. The Midwest and South, in particular, draw heavily from groundwater sources where manganese naturally accumulates. If you live in any of these states — especially in a rural area or a town with older pipes — it's worth knowing your actual manganese levels, not just assuming your water is fine.

The good news is that manganese is very effectively removed by the right filtration technology. Reverse osmosis (RO) systems are the gold standard, removing up to 99% of dissolved manganese from your tap water. Whole-house filtration systems that use oxidation and filtration — a process that converts dissolved manganese into a solid form that can then be filtered out — are also highly effective for treating water throughout your home. Standard pitcher filters and basic carbon filters are generally not enough on their own to address manganese at elevated levels. Echo Water's reverse osmosis systems are specifically designed to handle heavy metals like manganese, giving you clean water directly at the tap where your family drinks and cooks. If you're in one of the high-risk states or your home has older plumbing, getting your water tested is the smartest first step. From there, you can choose a filtration solution matched to your actual results — not just a best guess.

Regulatory Standards for Manganese*

Cities With the Highest Manganese* Levels

States Most Affected by Manganese*

Frequently Asked Questions

Related Contaminant Guides