Radon, arsenic, iron, lead, manganese, and sulfate are present in Brown County's groundwater and several of these contaminants exceed EPA health standards. Iron and manganese reach very high levels, sulfate is high, and sodium is moderate, making water quality a significant concern for well owners.
These contaminants come from the rock beneath the county. Iron and manganese dissolve naturally from the bedrock as groundwater moves through it. Radon is released from radioactive minerals in the same rock layers. Arsenic and lead also occur naturally in the soil and stone. Sulfate enters from the same geological sources.
This county's water is very hard, driven by elevated calcium and magnesium, and it contains very high iron and high sulfate. The bedrock here naturally releases these minerals into the groundwater as water filters down and stays in contact with the rock for long periods. Most wells across Brown County show these same mineral-rich conditions.
Radon, arsenic, iron, lead, and manganese are found at levels exceeding EPA health standards in Brown County wells. Radon is a radioactive gas that increases lung cancer risk. Arsenic and lead are toxic metals that can cause serious health problems, especially in children. Iron and manganese at elevated levels can affect brain development and organ function over time.
County well water is extremely hard, which means scale builds up inside pipes and appliances. You will see orange or brown staining on laundry, dishes, and fixtures from the iron content. The water may taste metallic or bitter. This extreme hardness can shorten the lifespan of water heaters and dishwashers.
Your well could have higher or lower levels than what is common in the county. We recommend getting your well tested with a comprehensive metals and minerals panel to know what is actually in your water. A comprehensive test runs $200-400 and is the only way to decide what treatment your well needs. Options like reverse osmosis filters or whole-home softeners can address multiple contaminants at once.
Not sure if your well is affected? Get certified results in 5–7 days.
Test Your Well Water with Tap Score →| Contaminant | Samples ⓘ | % Above MCL ⓘ | Distribution ⓘ | Confidence ⓘ | Risk ⓘ |
|---|---|---|---|---|---|
| Radon | 1 | 100% | Low | High ⓘ | |
| Iron | 111 | 90% | High | High | |
| Manganese | 99 | 88% | Moderate | High | |
| Arsenic | 101 | 32% | High | High | |
| Sulfate | 112 | 29% | High | High | |
| Lead | 101 | 2% | High | Low | |
| Fluoride | 111 | 0% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| Chloride | 121 | 0% | High | Low | |
| Nitrate | 14 | 0% | Low | Low | |
| Nitrite | 5 | 0% | Low | Safe ⓘ | |
| PFHxS ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| PFNA ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| PFOA ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| PFOS ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| Uranium | 1 | 0% | Low | Low ⓘ | |
| pH | 5 | — | Low | Low ⓘ | |
| PFBS ⓘ municipal | 4 | — | Low | Safe ⓘ | |
| Sodium | 111 | — | High | Low | |
| Hardness | 2 | — | Low | Low ⓘ |
MCL = Maximum Contaminant Level (EPA limit for public water; used as benchmark for private wells). Distribution shows % of sampled wells in each concentration band. Methodology.
* Microbial contaminants (E. coli, coliform) reflect only samples from the last 10 years.
Data shows potential risk — a certified test confirms whether your water is affected.
Order a Tap Score Test →Population-level CDC data. Not individual risk prediction.
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