Groundwater in Waukesha County contains iron, manganese, chloride, nitrate, nitrite, and PFOS/PFOA/PFHXS, along with sulfate. Several of these contaminants exceed EPA health standards and warrant attention.
These contaminants come from two sources. Iron, manganese, and sulfate dissolve naturally from the deep bedrock as groundwater moves slowly through it. Chloride enters from road salt spread on roads and parking lots during winter, while PFOS and PFOA are human-made chemicals that have entered the groundwater through industrial use and disposal.
Groundwater in this county is very hard, driven by elevated calcium and magnesium from the limestone bedrock below. As water sits in contact with this rock layer, it picks up these dissolved minerals over time. Very hard water is the standard across wells in this county, and elevated iron appears in many of them as well.
Wells in Waukesha County commonly exceed EPA health standards for chloride, iron, manganese, nitrate, nitrite, and PFOA and PFOS compounds. Chloride and nitrate can harm kidneys and affect blood pressure over time. Manganese exposure can damage the nervous system. PFOA and PFOS are industrial chemicals that build up in your body and have been linked to health concerns including immune system effects and thyroid issues.
Waukesha County has extremely hard water, which leaves white, chalky scale buildup on fixtures and inside pipes. Iron at elevated levels causes orange and brown staining on sinks, toilets, and laundry. This extreme hardness can shorten the lifespan of water heaters and dishwashers. Soap becomes less effective, making cleaning harder and using more product.
We recommend testing your well water with a comprehensive metals and minerals panel since multiple contaminants exceed standards here. Every well is different, and your well may have higher or lower levels than what is common in the county. Testing is the only way to know what is actually in your water so it can be properly treated. A comprehensive panel typically costs $200-400 and will guide your treatment choices, such as water softeners for hardness and iron removal systems.
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 ⓘ |
|---|---|---|---|---|---|
| Iron | 284 | 45% | High | High | |
| Manganese | 262 | 18% | High | High | |
| Chloride | 871 | 9% | High | Moderate | |
| Sulfate | 268 | 5% | High | Moderate | |
| PFOS ⓘ municipal | 131 | 5% | High |
Moderate
Elevated concentration, not % above limit
|
|
| PFOA ⓘ municipal | 131 | 4% | High |
Moderate
Elevated concentration, not % above limit
|
|
| PFHxS ⓘ municipal | 131 | 3% | High |
Moderate
Elevated concentration, not % above limit
|
|
| Nitrate | 298 | 1% | High | Low | |
| Nitrite | 233 | 0% | High | Low | |
| Arsenic | 63 | 0% | Moderate | Low | |
| Fluoride | 258 | 0% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 131 | 0% | High | Safe | |
| Lead | 59 | 0% | Moderate | Low | |
| PFNA ⓘ municipal | 131 | 0% | High | Low | |
| Radon | 16 | 0% | Moderate | Low ⓘ | |
| Uranium | 55 | 0% | Moderate | Low | |
| pH | 548 | — | High | Low | |
| Sodium | 207 | — | High | Low | |
| Hardness | 290 | — | High | Low | |
| PFBS ⓘ municipal | 131 | — | High | 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.
Loading recent water news…