We analyzed tap water quality data for hundreds of cities across the United States to identify those with the highest levels of barium. This ranking is based on 2026 data from the EPA and EWG databases.
Barium 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
Apollo, Pennsylvania
Apollo has barium detected at 2,030 ppb. 12 total contaminants were found in the water supply.
North Brunswick, Pennsylvania
North Brunswick has barium detected at 1,993.30 ppb. 10 total contaminants were found in the water supply.
Laceyville, Pennsylvania
Laceyville has barium detected at 1,940 ppb. 8 total contaminants were found in the water supply.
Aledo, Illinois
Aledo has barium detected at 1,820 ppb. 11 total contaminants were found in the water supply.
Rainelle, West Virginia
Rainelle has barium detected at 1,784 ppb. 15 total contaminants were found in the water supply.
Richmond, Pennsylvania
Richmond has barium detected at 1,645 ppb. 12 total contaminants were found in the water supply.
Pell Lake, Wisconsin
Pell Lake has barium detected at 1,480 ppb. 15 total contaminants were found in the water supply.
Perryville, Pennsylvania
Perryville has barium detected at 1,322.70 ppb. 5 total contaminants were found in the water supply.
Durham, Pennsylvania
Durham has barium detected at 1,300 ppb. 12 total contaminants were found in the water supply.
Holland, New York
Holland has barium detected at 1,282.50 ppb. 17 total contaminants were found in the water supply.
Freehold, New York
Freehold has barium detected at 1,238.50 ppb. 13 total contaminants were found in the water supply.
Gowanda, New York
Gowanda has barium detected at 1,235.80 ppb. 16 total contaminants were found in the water supply.
Nora Springs, Iowa
Nora Springs has barium detected at 1,190 ppb. 21 total contaminants were found in the water supply.
Pingree Grove, Illinois
Pingree Grove has barium detected at 1,164 ppb. 15 total contaminants were found in the water supply.
Knoxville, Pennsylvania
Knoxville has barium detected at 1,132.50 ppb. 11 total contaminants were found in the water supply.
Clayton, Louisiana
Clayton has barium detected at 1,126 ppb. 18 total contaminants were found in the water supply.
Pine Valley, New York
Pine Valley has barium detected at 1,103.80 ppb. 10 total contaminants were found in the water supply.
Gifford, Pennsylvania
Gifford has barium detected at 1,100 ppb. 13 total contaminants were found in the water supply.
Burlington, Illinois
Burlington has barium detected at 1,100 ppb. 13 total contaminants were found in the water supply.
Binghamton, Pennsylvania
Binghamton has barium detected at 1,093.90 ppb. 7 total contaminants were found in the water supply.
Genoa City, Wisconsin
Genoa City has barium detected at 1,088.40 ppb. 22 total contaminants were found in the water supply.
Pleasant City, Ohio
Pleasant City has barium detected at 1,070 ppb. 19 total contaminants were found in the water supply.
Cedar Valley, Utah
Cedar Valley has barium detected at 1,061.70 ppb. 6 total contaminants were found in the water supply.
Hampshire, Illinois
Hampshire has barium detected at 1,060.70 ppb. 13 total contaminants were found in the water supply.
Farmer City, Illinois
Farmer City has barium detected at 1,033 ppb. 14 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 Barium, Total trihalomethanes (TTHMs), Haloacetic acids (HAA5). These appear repeatedly across different water systems and regions.
Geographically, the states most represented in this ranking are Pennsylvania (9), Illinois (5), New York (4). Regional water sources, industrial activity, and agricultural runoff all contribute to local water quality variation.
Across all ranked cities, 235 contaminant readings exceed EWG health guidelines, but only 3 exceed EPA legal limits. This gap of 232 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 | Apollo | PA | 12 | 9 | 1 | 250 |
| 2 | North Brunswick | PA | 10 | 9 | 0 | 60 |
| 3 | Laceyville | PA | 8 | 7 | 0 | 0 |
| 4 | Aledo | IL | 11 | 6 | 0 | 200 |
| 5 | Rainelle | WV | 15 | 12 | 1 | 1,381 |
| 6 | Richmond | PA | 12 | 11 | 0 | 200 |
| 7 | Pell Lake | WI | 15 | 8 | 0 | 4,071 |
| 8 | Perryville | PA | 5 | 5 | 0 | 224 |
| 9 | Durham | PA | 12 | 10 | 0 | 325 |
| 10 | Holland | NY | 17 | 11 | 0 | 1,680 |
| 11 | Freehold | NY | 13 | 9 | 0 | 320 |
| 12 | Gowanda | NY | 16 | 13 | 0 | 2,919 |
| 13 | Nora Springs | IA | 21 | 11 | 0 | 1,369 |
| 14 | Pingree Grove | IL | 15 | 11 | 0 | 10,365 |
| 15 | Knoxville | PA | 11 | 9 | 0 | 590 |
| 16 | Clayton | LA | 18 | 13 | 1 | 723 |
| 17 | Pine Valley | NY | 10 | 7 | 0 | 82 |
| 18 | Gifford | PA | 13 | 10 | 0 | 850 |
| 19 | Burlington | IL | 13 | 9 | 0 | 0 |
| 20 | Binghamton | PA | 7 | 6 | 0 | 50 |
| 21 | Genoa City | WI | 22 | 13 | 0 | 0 |
| 22 | Pleasant City | OH | 19 | 13 | 0 | 447 |
| 23 | Cedar Valley | UT | 6 | 4 | 0 | 400 |
| 24 | Hampshire | IL | 13 | 9 | 0 | 7,758 |
| 25 | Farmer City | IL | 14 | 10 | 0 | 2,055 |
Frequently Asked Questions
What cities have the highest levels of barium?
Our analysis of 2026 data identified the cities with the highest detected levels of barium. See the full ranking above.
Is barium dangerous in drinking water?
Barium 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 barium 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 barium?
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.
