Groundwater in Allegheny County contains manganese, iron, radon, arsenic, chloride, and other contaminants at levels that exceed EPA health standards. These are serious concerns that deserve your attention.
The rock beneath Allegheny County is made of layered shale and sandstone from the Pennsylvanian era. Water moving slowly through cracks in these layers picks up iron and manganese naturally. Radon seeps in from radioactive elements scattered through the rock. Arsenic, chloride, and other minerals dissolve as water sits in contact with the stone for long periods underground.
Groundwater in this county is hard, with elevated iron and sodium from the bedrock minerals. These elements dissolve into water as it moves through the shale and sandstone layers that hold most wells in this area. Hard water with high iron and sodium is common across Allegheny County wells.
Wells in Allegheny County commonly exceed EPA health standards for radon, arsenic, chloride, iron, manganese, and PFOA and PFOS. Radon is a radioactive gas that increases lung cancer risk with long-term exposure through drinking water and showering. Arsenic damages kidneys and raises cancer risk. Manganese can harm brain development in children and affect the nervous system in adults. PFOA and PFOS are human-made chemicals linked to serious health problems including liver damage and thyroid disease.
Wells in this county are very hard water with high iron and sodium. You will see orange or reddish-brown stains on sinks, toilets, and laundry from iron buildup. White crusty scale forms on pipes and fixtures. The high sodium tastes salty. Hard water this extreme can shorten the lifespan of water heaters and dishwashers.
We recommend testing your well with a comprehensive metals and radon panel because multiple contaminants exceed health standards. 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. Treatment options like aeration systems for radon and water softeners for hardness can address these concerns.
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 ⓘ |
|---|---|---|---|---|---|
| Manganese | 48 | 92% | Moderate | High | |
| Iron | 66 | 73% | Moderate | High | |
| Radon | 3 | 33% | Low | High ⓘ | |
| Sulfate | 65 | 14% | Moderate | Moderate | |
| PFOS ⓘ municipal | 258 | 8% | High | Moderate | |
| Chloride | 66 | 8% | Moderate | Moderate | |
| Arsenic | 36 | 6% | Moderate | Moderate | |
| PFOA ⓘ municipal | 258 | 2% | High | Low | |
| PFHxS ⓘ municipal | 190 | 1% | High | Low | |
| Fluoride | 52 | 0% | Moderate | Low | |
| HFPO-DA (GenX) ⓘ municipal | 253 | 0% | High | Safe | |
| Lead | 39 | 0% | Moderate | Low | |
| Nitrate | 66 | 0% | Moderate | Low | |
| Nitrite | 30 | 0% | Moderate | Safe | |
| PFNA ⓘ municipal | 190 | 0% | High | Safe | |
| Uranium | 17 | 0% | Moderate | Low | |
| Hardness | 67 | — | Moderate | Low | |
| E. coli | 1* | 0% | Low | Low ⓘ | |
| Total Coliform | 1* | 0% | Low | Low ⓘ | |
| Sodium | 57 | — | Moderate | Low | |
| pH | 66 | — | Moderate | Low | |
| PFBS ⓘ municipal | 253 | — | 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…