We analyzed tap water quality data for hundreds of cities across the United States to identify those with the highest levels of bromodichloromethane. This ranking is based on 2026 data from the EPA and EWG databases.
Bromodichloromethane 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
Calvin, Louisiana
Calvin has bromodichloromethane detected at 66.90 ppb. 16 total contaminants were found in the water supply.
Ryan, Oklahoma
Ryan has bromodichloromethane detected at 59 ppb. 15 total contaminants were found in the water supply.
Paint Rock, Texas
Paint Rock has bromodichloromethane detected at 55.20 ppb. 23 total contaminants were found in the water supply.
Tullos, Louisiana
Tullos has bromodichloromethane detected at 51.50 ppb. 16 total contaminants were found in the water supply.
Burnet, Texas
Burnet has bromodichloromethane detected at 51.30 ppb. 25 total contaminants were found in the water supply.
Georgetown, Louisiana
Georgetown has bromodichloromethane detected at 45.50 ppb. 16 total contaminants were found in the water supply.
Waurika, Oklahoma
Waurika has bromodichloromethane detected at 45.10 ppb. 15 total contaminants were found in the water supply.
Millersview, Texas
Millersview has bromodichloromethane detected at 44.40 ppb. 22 total contaminants were found in the water supply.
Saline, Louisiana
Saline has bromodichloromethane detected at 41.30 ppb. 16 total contaminants were found in the water supply.
Clayton, Louisiana
Clayton has bromodichloromethane detected at 40.50 ppb. 18 total contaminants were found in the water supply.
Silverton, Texas
Silverton has bromodichloromethane detected at 39 ppb. 24 total contaminants were found in the water supply.
Wilmington, California
Wilmington has bromodichloromethane detected at 36.70 ppb. 17 total contaminants were found in the water supply.
Mount Erie, Illinois
Mount Erie has bromodichloromethane detected at 36.10 ppb. 15 total contaminants were found in the water supply.
Huron, California
Huron has bromodichloromethane detected at 35.90 ppb. 18 total contaminants were found in the water supply.
Quintana, Texas
Quintana has bromodichloromethane detected at 35.70 ppb. 22 total contaminants were found in the water supply.
Comanche, Oklahoma
Comanche has bromodichloromethane detected at 35.70 ppb. 14 total contaminants were found in the water supply.
Maysville, Oklahoma
Maysville has bromodichloromethane detected at 33.70 ppb. 14 total contaminants were found in the water supply.
Ridgecrest, Louisiana
Ridgecrest has bromodichloromethane detected at 32.60 ppb. 20 total contaminants were found in the water supply.
Lemoore, California
Lemoore has bromodichloromethane detected at 32.50 ppb. 24 total contaminants were found in the water supply.
Monterey, California
Monterey has bromodichloromethane detected at 31.20 ppb. 20 total contaminants were found in the water supply.
Wellton, Arizona
Wellton has bromodichloromethane detected at 30.80 ppb. 10 total contaminants were found in the water supply.
Springer, New Mexico
Springer has bromodichloromethane detected at 30.60 ppb. 19 total contaminants were found in the water supply.
Mathis, Texas
Mathis has bromodichloromethane detected at 30.50 ppb. 25 total contaminants were found in the water supply.
Troup, Texas
Troup has bromodichloromethane detected at 30.20 ppb. 17 total contaminants were found in the water supply.
Dubach, Louisiana
Dubach has bromodichloromethane detected at 30.20 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 Bromodichloromethane, Chloroform, Dibromochloromethane. These appear repeatedly across different water systems and regions.
Geographically, the states most represented in this ranking are Louisiana (7), Texas (7), Oklahoma (4). Regional water sources, industrial activity, and agricultural runoff all contribute to local water quality variation.
Across all ranked cities, 291 contaminant readings exceed EWG health guidelines, but only 32 exceed EPA legal limits. This gap of 259 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 | Calvin | LA | 16 | 10 | 1 | 591 |
| 2 | Ryan | OK | 15 | 11 | 1 | 800 |
| 3 | Paint Rock | TX | 23 | 12 | 2 | 275 |
| 4 | Tullos | LA | 16 | 10 | 2 | 792 |
| 5 | Burnet | TX | 25 | 12 | 2 | 375 |
| 6 | Georgetown | LA | 16 | 10 | 1 | 1,872 |
| 7 | Waurika | OK | 15 | 11 | 1 | 2,100 |
| 8 | Millersview | TX | 22 | 12 | 2 | 3,987 |
| 9 | Saline | LA | 16 | 11 | 1 | 783 |
| 10 | Clayton | LA | 18 | 13 | 1 | 723 |
| 11 | Silverton | TX | 24 | 13 | 1 | 597 |
| 12 | Wilmington | CA | 17 | 13 | 1 | 99 |
| 13 | Mount Erie | IL | 15 | 11 | 2 | 0 |
| 14 | Huron | CA | 18 | 12 | 1 | 7,306 |
| 15 | Quintana | TX | 22 | 13 | 1 | 231 |
| 16 | Comanche | OK | 14 | 12 | 1 | 1,649 |
| 17 | Maysville | OK | 14 | 10 | 2 | 0 |
| 18 | Ridgecrest | LA | 20 | 14 | 2 | 855 |
| 19 | Lemoore | CA | 24 | 14 | 1 | 27,038 |
| 20 | Monterey | CA | 20 | 12 | 1 | 136 |
| 21 | Wellton | AZ | 10 | 10 | 1 | 2,375 |
| 22 | Springer | NM | 19 | 12 | 1 | 1,170 |
| 23 | Mathis | TX | 25 | 13 | 1 | 5,037 |
| 24 | Troup | TX | 17 | 10 | 1 | 1,989 |
| 25 | Dubach | LA | 14 | 10 | 1 | 1,530 |
Frequently Asked Questions
What cities have the highest levels of bromodichloromethane?
Our analysis of 2026 data identified the cities with the highest detected levels of bromodichloromethane. See the full ranking above.
Is bromodichloromethane dangerous in drinking water?
Bromodichloromethane 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 bromodichloromethane 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 bromodichloromethane?
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.
