We analyzed tap water quality data for hundreds of cities across the United States to identify those with the highest levels of manganese. This ranking is based on 2026 data from the EPA and EWG databases.
Manganese is a contaminant of growing concern in drinking water. The cities below have the highest detected levels based on the most recent testing data available.
Rankings at a Glance
Schaller, Iowa
Schaller has manganese detected at 2,843.20 ppb. 18 total contaminants were found in the water supply.
Cumberland, Wisconsin
Cumberland has manganese detected at 2,646.70 ppb. 8 total contaminants were found in the water supply.
Pierre, South Dakota
Pierre has manganese detected at 2,500 ppb. 16 total contaminants were found in the water supply.
Pacific Junction, Iowa
Pacific Junction has manganese detected at 2,308.30 ppb. 11 total contaminants were found in the water supply.
Halcyon, California
Halcyon has manganese detected at 2,066.70 ppb. 3 total contaminants were found in the water supply.
Alta Vista, Iowa
Alta Vista has manganese detected at 2,040 ppb. 8 total contaminants were found in the water supply.
Ellinwood, Kansas
Ellinwood has manganese detected at 1,780 ppb. 8 total contaminants were found in the water supply.
Alton, Maine
Alton has manganese detected at 1,650 ppb. 7 total contaminants were found in the water supply.
Hazel Hurst, Pennsylvania
Hazel Hurst has manganese detected at 1,640 ppb. 7 total contaminants were found in the water supply.
Nicasio, California
Nicasio has manganese detected at 1,500 ppb. 15 total contaminants were found in the water supply.
Farnham Manor, Virginia
Farnham Manor has manganese detected at 1,337.40 ppb. 5 total contaminants were found in the water supply.
Pitkin, Louisiana
Pitkin has manganese detected at 1,282.50 ppb. 12 total contaminants were found in the water supply.
Moundsville, West Virginia
Moundsville has manganese detected at 1,281.70 ppb. 18 total contaminants were found in the water supply.
Yuma, California
Yuma has manganese detected at 1,260 ppb. 6 total contaminants were found in the water supply.
Hickman, California
Hickman has manganese detected at 1,008.70 ppb. 9 total contaminants were found in the water supply.
Jewell, Kansas
Jewell has manganese detected at 1,000 ppb. 12 total contaminants were found in the water supply.
Randall, Kansas
Randall has manganese detected at 1,000 ppb. 12 total contaminants were found in the water supply.
Barnard, Kansas
Barnard has manganese detected at 1,000 ppb. 12 total contaminants were found in the water supply.
Washingtonville, New York
Washingtonville has manganese detected at 1,000 ppb. 13 total contaminants were found in the water supply.
Grantham, New Hampshire
Grantham has manganese detected at 963.30 ppb. 2 total contaminants were found in the water supply.
Castana, Iowa
Castana has manganese detected at 962.20 ppb. 21 total contaminants were found in the water supply.
La Honda, California
La Honda has manganese detected at 961.60 ppb. 16 total contaminants were found in the water supply.
Linn Grove, Iowa
Linn Grove has manganese detected at 959.20 ppb. 15 total contaminants were found in the water supply.
Orem, Montana
Orem has manganese detected at 866.70 ppb. 17 total contaminants were found in the water supply.
Ayer, Massachusetts
Ayer has manganese detected at 843.10 ppb. 31 total contaminants were found in the water supply.
What We Found: Key Patterns
The most frequently detected contaminants exceeding health guidelines across these cities are Manganese, Total trihalomethanes (TTHMs), Haloacetic acids (HAA5). These appear repeatedly across different water systems and regions.
Geographically, the states most represented in this ranking are Iowa (5), California (5), Kansas (4). Regional water sources, industrial activity, and agricultural runoff all contribute to local water quality variation.
Across all ranked cities, 193 contaminant readings exceed EWG health guidelines, but only 7 exceed EPA legal limits. This gap of 186 highlights how legal standards may not fully protect public health — EPA limits haven't been updated for many contaminants in decades.
Full Rankings Table
| Rank | City | State | Detected | Above Guidelines | Above Legal | People Served |
|---|---|---|---|---|---|---|
| 1 | Schaller | IA | 18 | 7 | 0 | 729 |
| 2 | Cumberland | WI | 8 | 4 | 0 | 2,311 |
| 3 | Pierre | SD | 16 | 5 | 0 | 14,091 |
| 4 | Pacific Junction | IA | 11 | 9 | 0 | 0 |
| 5 | Halcyon | CA | 3 | 3 | 1 | 105 |
| 6 | Alta Vista | IA | 8 | 8 | 0 | 55 |
| 7 | Ellinwood | KS | 8 | 5 | 0 | 220 |
| 8 | Alton | ME | 7 | 4 | 0 | 65 |
| 9 | Hazel Hurst | PA | 7 | 5 | 0 | 140 |
| 10 | Nicasio | CA | 15 | 11 | 1 | 31 |
| 11 | Farnham Manor | VA | 5 | 3 | 0 | 77 |
| 12 | Pitkin | LA | 12 | 8 | 0 | 0 |
| 13 | Moundsville | WV | 18 | 9 | 0 | 9,911 |
| 14 | Yuma | CA | 6 | 2 | 0 | 151 |
| 15 | Hickman | CA | 9 | 6 | 0 | 26 |
| 16 | Jewell | KS | 12 | 10 | 1 | 365 |
| 17 | Randall | KS | 12 | 10 | 1 | 80 |
| 18 | Barnard | KS | 12 | 10 | 1 | 57 |
| 19 | Washingtonville | NY | 13 | 7 | 0 | 7,200 |
| 20 | Grantham | NH | 2 | 2 | 0 | 3,000 |
| 21 | Castana | IA | 21 | 12 | 0 | 0 |
| 22 | La Honda | CA | 16 | 11 | 0 | 832 |
| 23 | Linn Grove | IA | 15 | 12 | 0 | 0 |
| 24 | Orem | MT | 17 | 13 | 0 | 800 |
| 25 | Ayer | MA | 31 | 17 | 2 | 7,427 |
Frequently Asked Questions
What cities have the highest levels of manganese?
Our analysis of 2026 data identified the cities with the highest detected levels of manganese. See the full ranking above.
Is manganese dangerous in drinking water?
Manganese has known health risks at elevated levels. The EWG sets health guidelines that are often stricter than EPA legal limits to account for the latest research on long-term exposure.
How do I remove manganese from my water?
Reverse osmosis (RO) systems are the most effective at removing a wide range of contaminants. Check the specific contaminant details for recommended filtration technology.
What is the EPA legal limit for manganese?
EPA legal limits vary by contaminant and may differ from EWG health guidelines. See individual city reports for specific legal limit comparisons.
Related Reports
Data sources: Environmental Working Group (EWG) Tap Water Database, U.S. EPA Safe Drinking Water Information System (SDWIS)
Last updated: September 2026
Methodology: Contaminant levels are compared against both EPA legal limits (Maximum Contaminant Levels) and EWG health guidelines, which are often stricter and based on the latest scientific research.
